Lifestyle Interventions for Major Depressive Disorder (MDD): An Expert Consensus Statement From the American College of Lifestyle Medicine

Abstract

Objective: To identify statements of consensus on integrating lifestyle medicine (LM) into treating major depressive disorder (MDD) in adults to improve quality of care and patient health outcomes. Methods: Experts in MDD, primary care, and behavioral health followed an a priori protocol for developing consensus statements. Using an iterative, online Delphi process, panel members reported levels of agreement, and statements were classified as consensus, near consensus, or no consensus. Results: The panel identified 102 candidate statements addressing: (1) MDD and Lifestyle Risk: Assessment and Treatment, (2) Evaluation, Diagnosis, and Special Populations, (3) Nutrition and Gut Health, (4) Physical Activity, (5) Sleep, (6) Connectedness, (7) Substances and Environmental Factors, (8) Adherence to Treatment and Optimizing Treatment. After 3 iterations of an online Delphi survey, revisions, and removal of duplicative statements, 71 statements met criteria for consensus, 10 for near consensus, and 21 for no consensus. Consensus was reached on key topics that included the importance of lifestyle interventions for treatment and prevention of MDD, strategies for adoption, and benefits for health outcomes and treatment success. Conclusion: Using lifestyle interventions for treating MDD can be strengthened by applying these statements to improve quality of care, inform policy, and identify areas for future research.

Keywords

lifestyle medicine major depressive disorder MDD mental health consensus Delphi

“Poorer mental health in college students is associated with suboptimal lifestyle factors, including unhealthy food, insufficient sleep, lack of physical activity, and substance use.”

Background

Major depressive disorder (MDD), also known as clinical depression, is a common and disabling mental health condition.¹ At any point in a given year there is a 6% prevalence of MDD, with a lifetime risk of 11% to 15%, accounting for about 10% of primary care visits.² The mean age of onset is the mid-20s, affecting twice as many women as men, with attendant emotional distress and functional impairment.^2,3 MDD affects individuals across all socioeconomic contexts, irrespective of gross domestic product.^1,4 The World Health Organization considers depression the leading health cause of disability worldwide, because it affects over 300 million individuals, and the number of people living with MDD increased by 18% from 2005 to 2015.⁵ This trend is even more concerning for individuals with MDD and suicidal ideation, with a 29% increase in prevalence from 2009 to 2017 in the United States.⁶

Pharmacological and psychological approaches are effective for managing MDD, but they do not always achieve a comprehensive or sustained recovery. This is due to their limited ability to address comorbid chronic physical illnesses or their potential to cause adverse somatic side effects.^1,7,8 Side effects commonly associated with antidepressant medications include weight gain, sexual and cardiac dysfunction, osteoporosis, and sedation, which can pose challenges for long-term adherence and efficacy.^1,9 Antidepressant medications achieve remission of MDD in two-thirds of patients.^10,11 underscoring the need for treatment beyond medications and psychotherapy.

Lifestyle psychiatry is a burgeoning field of medicine rooted in evidence-based principles focused on helping individuals and families improve and sustain mental and physical health by adopting healthy lifestyle choices to optimize brain health, and to prevent or ameliorate various psychiatric disorders.^12-14 Healthy lifestyle habits, or pillars of lifestyle medicine (Table 1)—including a whole-food, plant-predominant diet, regular physical activity, restorative sleep, healthy stress management, strong connections, and avoiding harmful substances—can profoundly affect physical and emotional health, enhancing quality of life and longevity.¹⁴ Conversely, poor lifestyle choices can significantly deteriorate physical and mental health, exacerbate existing health issues, and reduce overall well-being.¹⁵

Table 1.

Six Pillars of Lifestyle Medicine Interventions.^a

Intervention	Description	Importance
Optimal nutrition	Eat more whole-foods and focus on minimally processed, plant-predominant, nutrient-dense meals and snacks	Extensive scientific evidence supports a whole-food, predominantly plant-based eating plan as an important strategy in preventing chronic disease, treating chronic conditions, and, in intensive therapeutic doses, reversing chronic illness. Such an eating plan is rich in fiber, antioxidants, and nutrient-dense, with a variety of minimally processed vegetables, fruits, whole grains, legumes, nuts, and seeds
Physical activity	Move every day and incorporate strength, flexibility, and aerobic activities into your routine	Regular and consistent physical activity combats the negative effects of sedentary behavior. Engaging in general physical activity and purposeful exercise regularly builds mental health, overall health, and resiliency
Stress management	Develop healthy coping skills to meet the ever-changing demands of life and bolster resilience	Stress, when moderate, may improve health and productivity but in excess can lead to anxiety, depression, obesity, immune dysfunction and more. Helping people recognize negative stress responses, identify coping mechanisms and stress reduction techniques leads to improved well-being
Restorative sleep	Create the right conditions to get 7-9 hours of quality sleep every night to allow the body to reset and recover	Inadequate or disordered sleep causes sluggishness, low attention span, decreased sociability, depressed mood, decreased daytime caloric burn, increased hunger, decreased satiety, insulin resistance, and decreased performance. Seven to 9 hours nightly is associated with optimal health; under 6 hours or more than 9 hours is associated with increased mortality
Connectedness	Foster supportive relationships and build connections that bring meaning and purpose to life	Positive social connections and relationships affect our physical, mental, and emotional health. Leveraging the power of relationships and social networks can help reinforce healthy behaviors
Risky substance avoidance	Avoid behaviors that include the consumption of or exposure to harmful substances	Tobacco and excessive alcohol consumption increase the risk of chronic diseases and death, with similar impact from opioids and recreational drug use. Treatments take time, requiring varying approaches and many attempts, with patience and support essential to cease risky substance habits

^aAdapted from the American College of Lifestyle Medicine’s 6 Pillars of Lifestyle Medicine.¹⁶

A growing body of evidence supports lifestyle medicine in managing and preventing MDD.^1,12 Notably, physical activity is a promising pillar of lifestyle intervention to benefit human well-being across biological, psychological, and social domains.⁸ While much of the evidence has been derived from studies in a general population, mounting evidence suggests this can be generalized to individuals with psychiatric conditions. Nonetheless, lifestyle interventions are grossly underutilized in clinical practice and are not systematically implemented in health care systems, because many clinicians are unfamiliar with the evidence supporting their efficacy.¹⁷ This highlights a missed opportunity, because adults with or without a lifetime diagnosis of mental illness overwhelmingly prefer non-pharmacologic treatment approaches despite awareness of the challenges with making sustained, healthy lifestyle changes.¹⁷

The rising prevalence of MDD and associated impact on individuals and families, including the potential adverse effects of medical therapy, create an essential need for evidence-based use of lifestyle interventions as cornerstones of preventing and managing MDD. Despite growing clinical research to guide clinicians, there is still uncertainty regarding which lifestyle interventions are most effective, how they can best be implemented, and how adherence can be sustained. Our objective was to find consensus among clinical experts on using lifestyle interventions when treating MDD, with the goal of helping clinicians and health care professionals identify best practices. Because of the existing uncertainties of gaps in evidence, we focused on identifying areas of expert consensus rather than developing a clinical practice guideline.

Methods

The American College of Lifestyle Medicine (ACLM) assembled a task force to review proposed topics of interest for an expert consensus statement (ECS), and the topic of lifestyle interventions for major depressive disorder was selected. The individual who proposed the topic to the task force (GM) was selected as ECS chair, and the assistant chair was identified through discussion between the chair, methodologist (RR), and staff liaisons (MK, KS). External stakeholder groups were identified and invited to nominate a member to serve on the ECS panel and represent the group’s position. These groups included representatives from the American Psychiatric Association, World Psychiatric Association, American Academy of Family Physicians, American Psychological Association, and World Federation of Societies for Biological Psychiatry. Additional panel members with topic expertise in mental health and/or lifestyle medicine were invited from the ACLM membership and a non-voting panel member represented the American College of Cardiology. Three ACLM staff served on the leadership panel, in the roles of methodologist (RR), primary staff liaison (MK), and secondary staff liaison (KS).

The methodology for this ECS followed the methodology used previously by ACLM to develop expert consensus statements.^18-20 First, conflicts of interest were reported and reviewed. A literature review in PubMed was conducted to identify abstracts on the topic of major depressive disorder and lifestyle medicine. Specific search strategies are presented in Supplemental Table S1. Searches focused on identifying systematic reviews and meta-analyses (n = 2374) and randomized controlled trials (n = 1562). Following screening of the abstracts, 173 systematic reviews/meta-analyses and 40 randomized controlled trials were identified as relevant and shared with the expert panel.

All meetings were held virtually. During the initial meeting, the expert panel developed a list of topics and constructed a PICO (population, intervention, comparator, outcome) framework for MDD, informed by their clinical experience and the needs of the stakeholder organizations. Topics focused on addressing controversial clinical issues, defining gaps in the evidence, improving quality of care, and promoting consistency in care. The (P)opulation of interest was identified as adults, aged 18 years or older; (I)nterventions were lifestyle change encompassing 1 or more of the 6 pillars of LM, and with any (C)omparator that allowed for the effect of the lifestyle change to be isolated from other medications, therapies, or medication intervention, with an (O)utcome of incidence, prevalence, or impact on major depressive disorder.

Following the first meeting, the panel proposed 75 potential topics related to quality improvement and voted on the importance of topics using an online survey, ranking each topic on a scale of 1 (least important) to 20 (most important). Mean rankings, along with standard deviation, and ranges were calculated for each of the 75 topics and shared for discussion at meeting 2. All surveys were conducted electronically using QuestionPro (https://www.questionpro.com/). Names were collected on the survey so the staff liaison could ensure completion and follow up accordingly; however, responses were deidentified by the staff liaison before being shared with other members of the panel.

At the second meeting, the topic list and rankings were reviewed, and based on the topics, a total of 102 consensus statements were drafted. The draft list was then edited by leadership to ensure clarity, consistency, and to avoid duplication. Following the meeting, panel members completed an online Delphi survey, ranking each of the proposed consensus statements on a 9-point scale from strongly disagree to strongly agree, where 1 = strongly disagree, 3 = disagree, 5 = neutral, 7 = agree, and 9 = strongly agree. Survey results were processed to identify statements that reached consensus, near consensus, or no consensus, using a priori criteria¹⁸ as follows:

Consensus: statements achieving a mean score of 7.00 or higher and having no more than 1 outlier, defined as any rating 2 or more Likert points from the mean in either direction

Near consensus: statements achieving a mean score of 6.50 or higher and having no more than 2 outliers

No consensus: statements that did not meet the criteria of consensus or near consensus

Near consensus and no consensus statements were discussed at meeting 3, and the panel decided which statements to revise and re-vote. Fifteen revised statements were included in the next Delphi survey, and the number of statements reaching consensus, near consensus, and no consensus were calculated and finalized during group discussion during meeting 4. All statements were collated, categorized under the appropriate topic, and the final list (including statements that reached consensus, near consensus, and no consensus) was shared with the panel.

Results

We reached consensus on 71 statements, spanning the topics of assessment and treatment, evaluation, diagnosis, and special populations, nutrition and gut health, physical activity, sleep, stress, connectedness, substances and the environment, adherence to treatment, and optimizing treatment.

Major Depressive Disorder and Lifestyle: Risk and Treatment

Eight statements achieved consensus (Table 2), highlighting physical activity as a primary therapy for adults with mild MDD, and the role of lifestyle interventions, in general, as effective, foundational components of managing MDD along with psychotherapy and psychopharmacology. One statement achieved near consensus, and 1 did not reach consensus (Tables S2 and S3). Of the 8 approved statements, 4 achieved consensus without any outliers. Topics of consensus included the use of physical activity as a primary therapy, the use of lifestyle interventions as an adjunct therapy, the importance of lifestyle interventions in managing MDD, and the impact of poor lifestyle habits on risk of MDD.

Table 2.

Statements That Reached Consensus on Risk and Treatment.

Number	Statement	Mean	Outliers
1	Physical activity can be used as primary therapy for reducing depressive symptoms in adults with mild MDD.	8.09	1
2	Lifestyle interventions can be used as adjunct therapy for reducing depressive symptoms in adults with moderate to severe MDD.	7.91	0
3	Lifestyle interventions are an integral part of managing adults with MDD and other related mood disorders.	8.00	1
4	Lifestyle interventions can be included in the treatment strategy for MDD.	8.45	0
5	Lifestyle interventions can be a foundational arm for treating MDD along with psychotherapy and psychopharmacology.	8.18	1
7	Unhealthy lifestyle habits can increase the risk of depressive symptoms progressing to MDD.	7.82	1
8	Lifestyle interventions can improve brain health and MDD outcomes through an impact on inflammation, HPA axis activity, sympathetic nervous system activity, and gene expression via epigenetics.	7.73	0
9	People with poor lifestyle habits are at greater risk of MDD.	7.73	0

Evaluation, Diagnosis, and Special Populations

Fifteen statements achieved consensus on evaluation, diagnosis, and special populations with MDD (Table 3). Two statements did not reach consensus (Table S3). The consensus statements highlight the feasibility of using validated instruments to evaluate baseline lifestyle habits with a low administrative burden, the critical importance of identifying modifying factors (e.g., barriers, psychological trauma, early life stressors, and adverse childhood events), and the need to distinguish depressive symptoms from MDD that fulfills current DSM criteria. Of the 15 approved statements, 7 achieved consensus without any outliers.

Table 3.

Statements That Reached Consensus on Evaluation, Diagnosis, and Special Populations.

Number	Statement	Mean	Outliers
10	Assessment of baseline lifestyle habits is required to implement lifestyle interventions for MDD.	7.64	1
11	Validated surveys or instruments are preferred when evaluating baseline lifestyle habits.	7.36	1
12	Several validated instruments/surveys with low administrative burden are available for assessing baseline lifestyle habits.	7.91	0
14	Assessing psychological and external barriers (such as SDOH) is necessary to treat MDD with lifestyle intervention.	7.73	1
15	Addressing psychological and external barriers (such as SDOH) can improve successful lifestyle behavior change.	8.00	0
16	Lifestyle habits can contribute toward an MDD diagnosis and should, therefore, be part of the baseline assessment in managing individuals with MDD.	7.82	0
27	Assessment of lifestyle habits is particularly important among women who are pregnant, postpartum, lactating, or peri/postmenopausal.	7.82	0
28	Addressing lifestyle habits among women who are pregnant, postpartum, lactating, or peri/postmenopausal can help plan lifestyle interventions to prevent or mitigate MDD.	7.55	0
30	Psychological trauma (e.g., physical abuse) increases the risk of MDD and is important to identify and address as part of management.	8.18	1
31	Providing trauma-informed care is important for the treatment of MDD.	8.27	1
32	ACEs (adverse childhood events) increase the risk of MDD and are important to identify for the purpose of implementing lifestyle interventions.	8.18	1
33	Early life stressors increase the risk of MDD and are important to identify and address as part of management.	7.55	0
34	Adults with MDD have depressive symptoms, but not all adults with depressive symptoms fulfill diagnostic criteria for MDD.	8.55	1
35	Current DSM criteria are the gold standard for diagnosing MDD.	7.82	1
36	Depressive symptoms include but are not limited to sad mood nearly every day for at least 2 weeks, hopelessness, helplessness, insomnia or hypersomnia, problems with concentration or appetite, and psychomotor changes (agitation and retardation).	8.45	0

Lifestyle Pillar: Nutrition and Gut Health

Eight statements on nutrition and gut health reached consensus (Table 4), 3 statements reached near consensus (Table S2), and eleven statements did not reach consensus (Table S3). Of the total 8 consensus statements, 3 of them achieved consensus without any outliers. Topics of consensus included the benefits of whole-food, plant-forward dietary patterns, low-carbohydrate dietary patterns, dietary risk factors for MDD, and the connection between the brain and gut microbiota. These statements support the benefits of a plant-forward eating pattern in preventing and managing MDD but would argue against a ketogenic or very low carbohydrate diet for management, based on unproven efficacy but well-documented adverse cardiovascular and health effects of these eating patterns.

Table 4.

Statements That Reached Consensus on Nutrition and Gut Health.

Number	Statement	Mean	Outliers
41	A whole-food, plant-based diet can help address metabolic issues associated with depression, side effects from pharmacotherapy, and elevated risks for chronic disease (CVD, stroke and DM) associated with MDD.	7.82	0
42	A more plant-forward approach, including Mediterranean-style eating pattern and higher intake of fiber and polyphenols, may be beneficial for MDD.	7.27	1
45	Dietary intake may play an important role in risk an individual has for developing MDD.	7.36	0
47	A Mediterranean-style eating pattern has benefits for adults with MDD.	7.36	1
52	There is insufficient evidence regarding the efficacy of ketogenic or very low carbohydrate diets in managing MDD, yet there is robust evidence on the adverse cardiovascular and health effects of these eating patterns.	7.82	1
53	A diet high in salt, saturated fats, fried foods, and refined carbohydrates, and low in fiber, is pro-inflammatory and associated with a higher risk of MDD.	7.82	0
57	There is a relationship between the brain and the gut that can trigger and improve MDD.	7.64	1
58	The brain-gut axis and the gut microbiota play a role in the development and treatment of MDD; these are affected by lifestyle factors including nutrition.	7.55	1

Lifestyle Pillar: Physical Activity

Twelve statements on physical activity reached consensus (Table 5) and 5 reached near consensus (Table S2). Of the total 12 consensus statements, 7 achieved consensus without any outliers. Key findings are that physical activity is the lifestyle intervention with the most compelling and robust evidence regarding efficacy for MDD and that regular physical activity, in general, is more important than the specific type of physical activity in terms of benefits for MDD. Conversely, sedentary activity may increase risk of MDD. Other topics of consensus included cardiovascular and muscle training, varieties and types of physical activity, increased effectiveness when combined with other treatment modalities, helpfulness of physical activity combined with social activity or mindfulness, strength of evidence for physical activity as compared to other lifestyle behaviors, and the factors that influence adoption and maintenance of physical activity patterns.

Table 5.

Statements That Reached Consensus on Physical Activity.

Number	Statement	Mean	Outliers
60	Cardiovascular training and muscle training are important for treating MDD and preventing complications.	7.82	0
62	Physical activity can be defined and expressed in various ways depending on patient communities.	7.55	0
63	Recommendations for physical activity in managing MDD should consider access to interventions based on health equity.	7.64	1
64	Physical activity as treatment for MDD is more effective when combined with other treatment modalities such as psychotherapy or pharmacological therapy.	7.36	1
66	Physical activity is the lifestyle intervention that has the most compelling and robust evidence regarding efficacy for MDD.	8.09	0
67	The specific type of physical activity recommended for MDD should be enjoyable for the individual, be consistent with their values, and be accessible.	7.64	0
68	Mindfulness-based physical activity, such as Tai Chi, Qigong, and yoga are specific therapeutic interventions that can be helpful for MDD.	7.45	1
69	The frequency, duration, and intensity of physical activity can impact efficacy for MDD outcomes.	7.82	1
70	Enjoyable activity is more desirable because of an increased likelihood of individuals maintaining it.	8.27	0
71	Social physical activity may be more helpful in supporting individuals to maintain it.	7.91	0
72	Regular physical activity in general is more important than the specific type of physical activity in terms of its benefits for MDD.	7.64	1
73	Sedentary behavior may increase risk for MDD.	7.82	0

Lifestyle Pillar: Sleep

Nine statements on sleep reached consensus (Table 6) and 1 statement did not reach consensus (Table S3). Of the 9 consensus statements, 8 achieved consensus without any outliers. There was strong consensus that the quality, quantity, and regularity of sleep have an impact on MDD and the risk, in general, for depressive disorders and neurocognitive deficits. In addition, there was consensus that adults with MDD have a high prevalence of obstructive sleep apnea, implying a need for screening and enhanced awareness among clinicians and health care professionals. Other topics of consensus included the importance of regularity, quality, quantity, and sleep preparation and the benefits of cognitive behavioral therapy (CBT) to improve insomnia.

Table 6.

Statements That Reached Consensus on Sleep.

Number	Statement	Mean	Outliers
76	Sleep regularity is an important component of overall sleep efficiency.	8.27	0
77	Quality, quantity, and regularity of sleep have an impact on MDD.	8.36	0
78	Cognitive behavioral therapy, both in-person and digital, can improve insomnia in adults with MDD.	7.73	0
79	Sleep disturbances associated with MDD can be improved with lifestyle interventions.	7.36	0
80	Regular, restful sleep is an effective intervention for neurocognitive deficits; conversely, lack of regular, restful sleep increases risk for neurocognitive deficits.	7.64	0
81	Evaluating and managing sleep disturbances can reduce risk of future depressive disorders.	7.45	0
82	Sleep preparation can optimize both sleep quantity and quality.	7.36	0
83	Sleep preparation includes avoiding blue light, avoiding caffeine after 5pm, and avoiding alcohol near bedtime.	7.82	0
84	There is a high prevalence of obstructive sleep apnea among adults with MDD.	7.36	1

Lifestyle Pillar: Stress and Social Connection

Seven statements on stress and social connection reached consensus (Table 7) and 1 statement did not reach consensus (Table S3). Of the 7 consensus statements, 4 achieved consensus without any outliers. There was strong consensus that social interventions—such as peer support, skill building, group-based activities, and links to community resources—can be effective in reducing adult depression. Other topics of consensus included lifestyle assessment to identify stress, conditions under which stress is a problem, distinction between social media vs social connection, and stress and social risk factors for MDD.

Table 7.

Statements That Reached Consensus on Stress and Social Connectedness Major Depressive Disorder and Lifestyle: Risk and Treatment.

Number	Statement	Mean	Outliers
86	Lifestyle assessment can identify stress and promote interventions to reduce stress.	7.45	1
88	Stress is a problem when overwhelming.	7.64	1
89	Relaxation (mind-body) management techniques are effective in treating adults with MDD.	7.55	1
90	Social media does not convey the same benefits as social connectedness.	7.91	0
91	Both loneliness and lack of social connectedness are predictors of onset of MDD.	7.91	0
92	A lack of a sense of belonging is associated with depression.	7.91	0
93	Social interventions (peer support, skill building, group-based activities, links to community resources) can be effective in reducing adult depression.	8.00	0

Lifestyle Pillar: Substances and Environmental Factors

Five statements on substances and environmental factors reached consensus (Table 8), 3 statements achieved near consensus (Table S2), and 1 statement did not reach consensus (Table S3). Of the 5 consensus statements, 4 achieved consensus without any outliers. Topics of consensus included the effects of exposure to drugs, cannabis, substance use and its association with social and economic challenges, as well as the potential of lifestyle modalities to promote neuroplastic change aiding recovery.

Table 8.

Statements That Reached Consensus on Substances and the Environment.

Number	Statement	Mean	Outliers
94	Lifestyle modalities can help promote neuroplastic change and aid in substance use recovery.	7.82	1
95	A history of drug ingestion is associated with a higher risk of depression, MDD, and suicidal ideation.	7.73	0
96	Cannabis use is associated with a higher prevalence of depression and anxiety.	7.73	0
98	There is a strong correlation between substance use and MDD and other mental health disorders.	7.82	0
99	Social determinants of health, such as food insecurity and homelessness, increase the risk for MDD and may impact the success of interventions.	8.55	0

Adherence to Treatment and Optimizing Treatment

Seven statements about adherence and optimization of lifestyle treatment reached consensus (Table 9). Together, these statements highlight the importance of specific individual traits and the psychosocial context to treatment adherence and optimization, as well as consideration factors within lifestyle interventions such as duration and method of integration. Expert panel members agreed that treatment adherence and optimization were more likely if individuals demonstrate a willingness to change and self-efficacy skills. Additionally, they agreed that the presence of social support (either from peers, family, or community) and access to resources enhances potential for adherence and optimization. These resources include the coordination of care across an interdisciplinary team. The expert panel concluded that lifestyle treatments are more likely to be adhered to and optimized when they are seamlessly integrated into an individual’s daily routine and maintained consistently over time.

Table 9.

Statements That Reached Consensus on Adherence to Lifestyle Treatment and Optimizing Treatment.

Number	Statement	Mean	Outliers
17	Lifestyle intervention is most effective when an individual has access to needed care/services, has a good support system (peers, family, community), and is motivated to change their lifestyle.	7.64	1
18	Lifestyle interventions are more successful in individuals who demonstrate readiness to change.	7.82	0
19	Lifestyle interventions are more successful when sustained over time.	8.73	0
22	Lifestyle interventions are more successful with social support from family, peers, or community.	7.91	1
23	Lifestyle interventions are most successful if integrated into daily activities as opposed to discrete periods of time.	7.82	0
24	Lifestyle interventions are more successful in individuals who demonstrate self-efficacy skills.	7.27	0
25	Coordination across the interdisciplinary team can help optimize lifestyle treatment for MDD.	7.55	0

One statement reached near-consensus and 1 did not reach consensus (Table S3). Both centered on the theme of specificity in care delivery. Expert panel members noted that these points were either sufficiently addressed by other consensus statements or lacked adequate supporting evidence.

Discussion

Using a validated and trustworthy process for assessing expert consensus, we have found broad agreement that lifestyle interventions (Table 1) have a significant, and foundational role, in managing and preventing MDD in adults. Physical activity has the strongest evidence base supporting its efficacy as a primary therapy for mild MDD, with additional evidence supporting the role of lifestyle interventions, in general, as adjunctive therapy for MDD along with psychotherapy and psychopharmacotherapy. Implementing lifestyle change begins with assessing baseline lifestyle habits and the individual’s readiness to change, which our experts concurred can be done with validated instruments. Other key areas of consensus include the benefits of a plant-forward eating pattern, limiting sedentary activity, optimizing sleep quality, using social interventions, and implementing strategies to support and sustain lifestyle change over time. These consensus statements should help raise awareness of lifestyle interventions for MDD and help clinicians and health care professionals optimize patient care.

Major Depressive Disorder and Lifestyle: Risk and Treatment

Mental health disorders significantly contributed to the global health burden of disease before, during, and after the COVID-19 pandemic.^3,21,22 A persistent barrier exists in accessing well-being resources, psychiatric medications, and psychotherapy, despite the increasing number of such treatments. This lack of access remains a challenge across all socioeconomic strata and countries, regardless of their wealth,²³ and highlights the importance of more readily accessible lifestyle interventions to improve physical and mental health.¹

Lifestyle interventions are an effective adjunctive therapy to conventional treatment for adults with MDD. For example, a meta-analysis of 96 randomized controlled trials found small, but significant effect sizes for the ability of lifestyle interventions to lower depression symptoms, anxiety symptoms, and feelings of stress.²⁵ A proposed mechanism of action may be the impact of these interventions on neuroinflammatory processes that have been linked to mental illness.^26,27 This is reflected in the consensus statement (Table 2) noting that lifestyle interventions can improve brain health and MDD outcomes through an impact on inflammation, HPA axis activity, sympathetic nervous system activity, and gene expression via epigenetics. As to gene expression, exercise enhances neurotrophic factors (i.e., brain-derived neurotrophic factor (BDNF), serotonin, etc.) promoting neuronal growth and synaptic connections in the hippocampus and other brain regions.²⁴

The consensus statement (Table 2) noting that people with poor lifestyle habits are at greater risk of MDD is supported by robust evidence from systematic reviews and prospective studies. In 1 cohort study,²⁵ the odds of developing depressive symptoms increased nearly 4-fold for adults sleeping less than 6 hours nightly, and nearly 2-fold for those with a poorly balanced diet or inadequate physical activity. Similarly, poorer mental health in college students is associated with suboptimal lifestyle factors, including unhealthy food, insufficient sleep, lack of physical activity, and substance use.^26,27 Last, a systematic review of nearly 300 studies noted that poor diet, sedentary behaviors, and tobacco and cannabis all conferred similar risk to developing mental health symptoms.²⁸

Evaluation, Diagnosis, and Special Populations

The gold standard for diagnosing MDD (Table 3) are the criteria outlined in the Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition (DSM-5-TR),²⁹ which require at least 5 of 9 symptoms—such as depressed mood, anhedonia, fatigue, changes in sleep or appetite, and suicidal ideation—for a minimum of 2 weeks, with evidence of functional impairment. Whereas the DSM-5-TR criteria remain the clinical standard for diagnosing MDD, expert consensus supports a more comprehensive evaluation that integrates lifestyle factors, psychological history, and social determinants of health (Table 3). Assessing baseline behaviors such as physical activity, sleep hygiene, dietary habits, substance use, and psychosocial stressors, including trauma exposure, can inform diagnostic clarity and can assist in developing personalized lifestyle-based interventions.

The expert panel emphasized applying a culturally informed and equity-oriented approach to diagnosing and treating adults with MDD. Cultural expressions of depression may differ significantly across racial and ethnic groups, and conventional DSM-5-TR criteria may not fully capture these variations. For example, somatic presentations or culturally specific idioms of distress may be more prevalent in some populations. Moreover, the influence of racial discrimination, intergenerational trauma, and differential access to care can impact both the clinical presentation and response to treatment. Incorporating these contextual and structural factors into the diagnostic framework enables more accurate recognition of MDD and supports more equitable and effective care, particularly when integrating lifestyle interventions.

Lifestyle Pillar: Nutrition and Gut Health

The human brain consumes about 20-25% of the body’s energy,³⁰ with a growing appreciation for the complex interplay between the foods we eat and how our brains react to nutrition.^31-33 Regrettably, diet-related risk factors account for about one-quarter of adult deaths and nearly one-fifth of adult disability-adjusted life years globally.³⁴ A key concern is the escalating consumption of ultra-processed foods (UPFs) that contain excessive amounts of refined sugars, unhealthy fats, and sodium, along with poor nutrient content and very low dietary fiber.³¹ UPFs comprise approximately 60% of the typical U.S. diet, consistent across genders and races,³⁵ and global consumption continues to rise.³⁶

Our expert panel agreed (Table 4) that a diet high in salt, saturated fats, fried foods, and refined carbohydrates, and low in fiber (e.g., high in UPFs) is associated with a higher risk of MDD. This conclusion is supported by cross-sectional research showing an eating pattern high in UPFs is associated with an 81% higher risk of developing depression, a 22% higher risk of reporting more mentally unhealthy days, and a 40% reduced likelihood of reporting zero unhealthy days.³⁷ Potential explanations for these associations include dysregulated neuroimmune responses,³⁸ increased neuroinflammation,^39,40 and alterations within the neuroendocrine system.³⁹

The emphasis on a whole-food, plant-predominant eating pattern (Table 4) in preventing and managing MDD in adults is based on systematic reviews of observational studies and randomized trials. A meta-analysis of 21 cross-sectional studies and 20 longitudinal studies found that individuals following the Mediterranean diet (MD) had a 33% lower relative risk of developing depression.⁴¹ Another systematic review of 16 randomized controlled trials noted that dietary interventions (e.g., decreasing unhealthy food intake, improving nutrient intake, or restricting calorie intake) improved depressive symptoms compared to controls, with a small, but significant effect size.³⁹ When adults with moderate to severe depression were randomized for 12 weeks to nutritional counseling encouraging healthy eating (avoiding fast food and UPFs) vs no counseling, the counseling group had large benefits with a number needed to treat (NNT) of only about 4 adults to improve depressive symptoms.⁴² In contrast, the NNT of 7 for most antidepressants to achieve a similar benefit is nearly twice as high.⁴³ In addition, a meta-analysis of epidemiological studies showed that every increase in 100 g of whole fruits or vegetables corresponded with a 5% reduction in the risk of depression.⁴⁴

Two other points from our consensus findings merit emphasis. First, our experts have suggested (Table 4) that a plant-forward diet helps improve gut microbiota health, which will improve dysregulated neuroimmune responses, increased neuroinflammation, and alterations within the neuroendocrine system.^31-33 Second, there was consensus that current evidence is insufficient to support the efficacy of ketogenic or very low-carbohydrate diets in managing MDD, but the evidence is robust regarding the adverse cardiovascular and health effects of these eating patterns. A recent narrative review noted that despite favorable case reports and animal models suggesting possible antidepressant and pro-cognitive effects of a ketogenic diet, there were significant knowledge gaps regarding the mechanisms of action, the predictors of response, long-term efficacy, tolerability, and feasibility of this eating pattern, and the level of ketosis needed to produce benefits.⁴⁵

Lifestyle Pillar: Physical Activity

The expert consensus on physical activity as effective, primary treatment for MDD (Table 5) is supported by several systematic reviews.^46-49 A review of 41 randomized controlled trials found large effects favoring exercise in adults diagnosed with MDD, resulting in a NNT of only 2 adults,⁴⁹ which is much lower than the NNT of 7 for selective serotonin uptake inhibitors.⁴³ Another systematic review of 15 cohort studies found that adults meeting recommended volumes of weekly physical activity had a 25% lower risk of MDD or depressive symptoms than those who were inactive, and even suboptimal levels of physical activity reduced risk by 18%.⁴⁸ Last, a meta-analysis of 218 randomized trials of adults with MDD concluded that compared to usual care, moderate, dose-dependent reductions in depression were found for walking, jogging, yoga, strength training, and tai chi or qigong.⁴⁶

The experts agreed (Table 5) that social physical activity may help individuals to maintain it, which is supported by a study showing that an 11-week social network-based program implemented among U.S. college students only noted a significant improvement in exercise when a social comparison component was included.⁵⁰ Social support is a widely used strategy for behavior change, because when individuals with similar interests interact to achieve a shared goal, the perceived costs of adopting a new exercise routine are reduced through companionship in the activity.⁵⁰ The peer support model, in general, has been shown to improve adherence to exercise programs among adolescents,⁵¹ individuals with severe mental illness,⁵² and individuals recovering from cancer treatment.⁵³

A sedentary lifestyle may increase the risk for MDD (Table 5), especially among adolescents. A national survey of youth behavior noted a relationship between feeling sad and hopeless among adolescents who did not meet the weekly aerobic physical guidelines, did not play on at least 1 team sport, or played video or computer games for more than 2 hours daily.⁵⁴ Similarly, individuals who changed from a physically active to a sedentary lifestyle during the COVID-19 pandemic were significantly more likely to develop depression, loneliness, and stress compared to those who maintained a sedentary lifestyle before and after the pandemic.⁵⁵

The beneficial effects of physical activity on depression are believed to stem from various mechanisms, including the release of endorphins, improvement in neuroplasticity, reduction in inflammation, and enhancements in sleep quality. Exercise also promotes social interaction and can improve self-esteem and mood, addressing other lifestyle pillars (Table 1).^56-61

Lifestyle Pillar: Sleep

The relationship between poor sleep quality—including insomnia, hypersomnia, and circadian disruptions—and major depressive disorder (MDD) is widely acknowledged as a significant contributor to worsening depressive symptoms and MDD.^60,62 Experts agree (Table 6) that disrupting the quality, quantity, and regularity of sleep can exacerbate emotional, cognitive, and physical functioning, amplifying the severity of MDD. Sleep loss significantly reduces positive emotions and increases anxiety symptoms, with effects observable even after minor sleep disruptions.⁵⁹ CBT for insomnia (CBT-I), delivered through both in-person and digital platforms, has demonstrated efficacy in improving sleep among adults with MDD.^57,60,63 Similarly, there is consensus that multicomponent lifestyle medicine interventions improve sleep quality, with notable effects post-intervention and during short-term follow-ups.⁶⁴ The importance of sleep screening is well established, particularly for individuals with clinical sleep disturbances, reinforcing the notion that sleep evaluation should be a standard part of depression management.

The last consensus statement in Table 6, regarding the high prevalence of obstructive sleep apnea (OSA) among adults with MDD, is of particular importance, given the potential morbidity from OSA and availability of effective treatment. The prevalence of OSA in adults with MDD is about 36% in clinical studies and 20% in population cohort studies, with increasing age and higher body mass index as significant predictors. Similarly, longitudinal studies of adults with OSA demonstrate over a 2-fold increased risk of developing MDD compared to adults without OSA.⁶⁵ These data suggest a need to screen adults with MDD for OSA, especially if they are elderly or with obesity or overweight, given the well-documented association of OSA with neurocognitive dysfunction and cardio-metabolic diseases.⁵² Treating OSA in adults with MDD (e.g., continuous positive airway pressure, weight reduction, possible surgery) is important to prevent cardiovascular morbidity.

Several statements related to the interaction between sleep deprivation and depression underwent revisions due to controversy or lack of sufficient evidence. For example, while experts initially debated the role of sleep deprivation as an antidepressant intervention, revised analyses clarified the complexity of this relationship: brief sleep deprivation (<7 days) slightly worsens depression, moderate duration (7-14 days) shows antidepressant effects, and prolonged sleep deprivation (>14 days) again exacerbates depressive symptoms.⁵⁸ The specific type of CBT demonstrated to be effective for insomnia is cognitive behavioral therapy for insomnia (CBT-I).⁶⁶ Additionally, while CBT-I for insomnia was widely supported as an effective intervention for treating sleep disturbances and depression, there was initial debate regarding whether the benefits extend beyond sleep quality improvements. A systematic review confirmed that CBT-I for insomnia significantly enhances depression response rates, solidifying consensus on its broader mental health benefits.⁵⁷

Lifestyle Pillar: Stress and Connectedness

Stressful life events predict the onset and course of depressive episodes through independent cognitive and biological responses.⁶⁷ Our expert consensus panel unanimously agreed that patient stress levels and the extent of unregulated stress need to be evaluated and addressed in managing adults with MDD. Emerging evidence underscores the need to integrate stress physiology—particularly the concept of “weathering”—into our understanding of MDD risk. The weathering hypothesis describes accelerated biological aging in Black populations from the cumulative impact of political marginalization and socioeconomic disadvantage.⁶⁸ Weathering is also impacted by allostatic load, the cumulative wear-and-tear on the body from inability to downregulate stress response systems from repeated challenges or instability during change.⁶⁹ Allostatic load scores are higher for Blacks than for Whites at all ages, independent of socioeconomic status, with an increasing differential as age progresses.⁷⁰ This physiological burden from chronic social adversity may sensitize individuals to depressive episodes and should inform diagnostic assessment and lifestyle-based therapeutic strategies.

Social connectedness is a basic human need that exerts a powerful buffering effect against depression, while loneliness and isolation—as heightened during and after the COVID-19 pandemic—are potent risk factors. While there is no universal definition of social connectedness, it is considered to include: social support, social networks, and an absence of social isolation and loneliness.⁷¹ Social connectedness fits within a larger context of overall connectedness to address core psychological relationships with oneself, others, and the world.^72,73

Up to 50% of U.S. adults reported significant loneliness even before the COVID-19 pandemic, with rates doubling among older adults aged 50 to 80 years during lockdowns. Systematic reviews link loneliness in older populations to increased depressive symptoms, cognitive decline, cardiovascular risk, and mortality. Longitudinal studies in younger and midlife adults (25 to 45 years), and older populations (65 years or older), confirm that reduced social contact—exacerbated by pandemic-induced restrictions—is associated with subsequent increases in depressive symptoms. Our expert consensus panel agreed on the need for social interventions in depression management (Table 7). A systematic review⁷⁴ of interventions showed that identifying opportunities to connect with others and psychological interventions targeting skills to manage maladaptive attributional biases, fear-related avoidance of social situations, and barriers to social contact can foster meaningful social connections.

Our experts also concurred (Table 7) that social media does not convey the same benefits as social connectedness. The surge in social media and digital technology use during the COVID-19 pandemic is linked to a decline in adolescent mental health. Specifically, these usage patterns correlate with increased depression, anxiety, loneliness, feelings of disconnectedness, poor body image, eating disorders, and suicidality among teenagers.^75-77

Lifestyle Pillar: Substances and Environmental Factors

The negative impact of alcohol use disorders (AUD) and other substance use disorders (SUD) continues to grow and affect the United States as well as the world.^78-92 There was consensus (Table 8) that there is a strong correlation between SUD, MDD, and other mental health disorders. Population-based estimates in the US show an annual mean prevalence of AUD or SUD of 9.4% in emergency department visits and 11.9% hospitalizations, reflecting relative increases, respectively of 30% and 57% from 2014 to 2018.⁸⁷ Moreover, there was coexisting depression in about 25% of visits when SUD or AUD were diagnosed, compared to only about 10% when neither were present.⁸⁷

There was expert consensus (Table 8) that substance use is associated with a higher risk of depression, MDD, and suicidal ideation. This statement is supported by survey data showing that individuals with an AUD and MDD were 9 times more likely to develop suicidal ideations within the year compared to individuals with MDD alone, SUD alone, or neither.⁸⁶ Similarly, individuals with cannabis use disorder were 11 times more likely to develop suicidal ideations, and individuals with SUD (excluding primary alcohol or cannabis) were 16 times more likely.⁸⁶ Further, a systematic review found that SUD was associated with over a 2-fold increased risk of suicidal ideation and suicide attempt, and a 50% increased risk of death by suicide.⁹³

With the increasing legalization of cannabis within the U.S.,⁹⁴ there is growing concern about the impact of cannabis, particularly in adolescent populations.^78,95 There was consensus that cannabis use is associated with a higher prevalence of depression and anxiety (Table 8), which is supported by about 40% increased odds of developing depression for cannabis users in young adulthood compared with nonusers.⁸¹ There are multiple theories regarding the link between anxiety or depression and substance use, but the data are still inconclusive regarding the temporal relationships between SUD and mental health symptoms.⁷⁹ Continued substance use, however, can result in neuroplastic changes in the brain that heighten binge/intoxication, withdrawal/negative affect, and preoccupation/anticipation behaviors.^83,84 Substance use also reduces treatment adherence, decreases recovery capital, and adherence to healthy lifestyle.^96,97 There was consensus (Table 8) that lifestyle modalities can help promote neuroplastic change and aid in substance use recovery, and the role of lifestyle medicine as adjunctive therapy for SUD has been described.⁸⁹

There was consensus (Table 8) that access to supportive care for MDD can be affected by environmental factors that include climate, food insecurity, and other social determinants of health. Key individual risk factors for developing SUD after initial drug use include genetics, adverse childhood experiences, developmental stage, personality traits, and existing mental health disorders.⁸⁷ These risks are often mediated by social factors such as family and community support, social inequalities, and cultural norms surrounding drug use. The specific characteristics of drugs and their availability also influence addiction risk and progression.^80,82,90

There were 2 similar statements regarding environmental exposure and MDD that nearly achieved consensus: air pollution (specifically particulate matter) may be associated with depression, and exposure to air pollution, smoke inhalation, and extreme heat increases the risk of developing depression. Nevertheless, a growing body of literature supports the correlation between MDD and exposure to air pollution, smoke inhalation, and excessive heat.^{85,88,91,98-100}

Adherence to Treatment and Optimizing Treatment

Equally important to lifestyle interventions are strategies to promote adherence to the recommendations that lead to sustained behavior change. The importance of promoting adherence is reflected in several of the expert consensus statements (Table 9), but the supporting evidence is often indirect and not specifically based on clinical trials of adults with MDD. Motivational interviewing, for example, is a common framework for delivering behavior change that can improve glycemic management in adults with type 2 diabetes but may not be effective in treating their depressive symptoms.¹⁰¹ Similarly, motivational interviewing for individuals with depression following traumatic brain injury offered no significant benefits beyond CBT and non-directive counseling.¹⁰² Conversely, combining motivational interviewing with CBT did offer small, but significant, treatment benefits for adults with MDD and AUD.¹⁰³ Whereas motivational interviewing may not offer consistent treatment benefits for MDD, it is useful for assessing an individual’s readiness to behavior change and can be combined with the Transtheoretical Model of Change or Stage of Change Model to align intervention with the person’s current state of change.¹⁰⁴

Self-efficacy and access to social support from family, peers, or the community were also considered important in managing MDD and sustaining lifestyle behavior change (Table 9). Self-efficacy, an individual’s belief in their ability to succeed, is integral to behavior change and a key aspect of self-management can be assessed using validated measures.¹⁰⁵ Although information on self-efficacy and MDD outcomes is limited, interventions to improve self-efficacy, in general, are effective in promoting health behavior change.¹⁰⁶ Social support-based interventions (e.g., social participation, social connections/networks) are effective in preventing depression,¹⁰⁷ and reducing depressive symptoms and to improve quality of life in older adults.^108,109 Similarly, peer support, provided by other individuals with the same health condition, can reduce depression and anxiety in adults with cancer while also improving self-efficacy and quality of life.¹¹⁰ For adults with depression, in general, peer support interventions have significant benefits over standard care, with professional-led psychotherapy and exercise programs showing more effectiveness than peer support discussions.¹¹¹

Considering the various challenges patients with depression face to develop and maintain behavior change, in managing adults with MDD, clinicians and health care professionals are better equipped to provide patient-centered care if they understand the barriers (unsure what to do, personal identity, low beliefs about one’s capabilities and the consequences, lack of motivation, lack of resources, negative social influences, and negative emotion) and facilitators (reinforcement from others, resources, positive social influences and/or support, positive emotion, and self-monitoring) to health behavior change. Our expert panel agreed (Table 9) that the most effective and/or successful lifestyle medicine interventions in working with patients with MDD are those that coordinate with an interprofessional care team (including patients and their support systems), provide access to needed care or services, build patients’ belief in their capacity to change their health behavior, identify patients’ reasons for wanting to make changes in their health behavior and their readiness to do so, integrate interventions into patients’ daily activities to make them an easy choice, and are sustained over time. In summary, effective and optimal lifestyle treatment relies on a combination of individual, social, and system-level integration.

Strengths and Limitations

The primary strength of our research is a trustworthy, time-tested, a priori protocol for creating statements and assessing consensus with an anonymous, online, survey platform based on mean levels of agreement and the number of outliers.¹⁸ Validity is also enhanced by having a diverse, but limited, number of panel experts, drawn from the disciplines of psychiatry, psychology, primary care, cardiology, and lifestyle medicine. The ability of this panel to reach consensus, using strict criteria, on about 70% of the initial candidate statements would not have been possible unless the statements were clear, concise, pragmatic, and evidence-based. Unfortunately, the evidence base was considered suboptimal by our panel to support developing a full, multi-disciplinary clinical practice guideline, with clear and actionable recommendations. A limitation, therefore, of our work is that we do not offer concrete recommendations for action by clinicians and health care professionals but rather seek to inform best practice based on areas of objectively shown consensus. The limitations in research evidence are related to gaps regarding the lifestyle pillars and primarily indirect evidence (not specifically for adults with MDD) regarding readiness to change, behavior modification, and support systems.

Conclusions

We have shown strong consensus among diverse experts that lifestyle interventions (Table 1) are a foundation of effective care for individuals with MDD but may be an underappreciated and underutilized approach. When viewed in terms of NNT for benefit, only 2 adults with MDD are needed to benefit from a physical activity regimen compared to 7 for selective serotonin uptake inhibitors, and only 4 adults are needed to benefit from nutritional intervention compared to 7 for most antidepressants. Beyond their benefits as primary or adjunctive therapy, maintaining healthy lifestyle habits is one of the best ways to reduce an individual’s risk of developing depressive symptoms, MDD, or cognitive decline.

Table 10 summarizes some of the key concepts from the consensus statements and their implications for patient care. The actions in this table are only suggestions, recognizing that our primary goal was to identify areas of expert consensus to guide care, not to make prescriptive recommendations as would occur in a clinical practice guideline. Beyond the many statements that achieved consensus, readers may also find it instructive to review the 10 statements achieving near consensus in Table S2 and the 21 statements that did not reach any consensus in Table S3. Although many of these statements appear to “make sense” and have face validity, the inability to reach consensus highlights the existing gaps and uncertainties in the literature that influence our expert panel. Our hope is that ongoing research will address these needs and will facilitate a future multi-disciplinary, clinical practice guideline with action-oriented recommendations and implementation tools.

Table 10.

Implications of Expert Consensus Statements on Lifestyle Medicine for Depression.

Domain	Expert Consensus Statement Summary	Suggestions for Clinicians
Risk and treatment (Table 2)	Lifestyle interventions are integral for managing adults with MDD as part of primary (physical activity) or adjunctive therapy; conversely, poor lifestyle habits place adults at greater risk for MDD.	Inquire regarding baseline lifestyle habits for adults with MDD or at-risk for MDD; educate patients on how physical activity and other lifestyle habits can prevent MDD and be adjunctive treatment along with psychotherapy and medications.
Evaluation, diagnosis, and special populations (Table 3)	Lifestyle interventions for MDD require baseline assessment of habits with validated measures, identifying special populations^a and ensuring a diagnosis that meets DSM-5-TR criteria.	Integrate validated measures for assessing lifestyle habits into routine patient care; recognize modifying factors and special populations that can impact MDD management.
Nutrition and gut health (Table 4)	A plant-predominant eating pattern with whole, fiber-rich foods and minimal UPFs can reduce MDD risk and can benefit adults with MDD; the brain-gut axis and microbiota can trigger or improve MDD based on lifestyle factors that include nutrition.	Advocate for a plant-predominant eating pattern in preventing and managing MDD and discourage a ketogenic or very low carbohydrate eating pattern because of unproven benefits for MDD but well-documented adverse health and cardiovascular effects.
Physical activity (Table 5)	Physical activity is the lifestyle intervention with the most robust evidence of efficacy for MDD, is most effective when combined with psychotherapy or medication, and ideally is enjoyable and consistent with the individual’s values.	Discuss and prescribe physical activity for adults with MDD, recognizing that regular activity is more important than the specific type; discuss how sedentary time can negatively impact physical health.
Sleep (Table 6)	The quality, quantity, and regularity of sleep have an impact on MDD; CBT can improve insomnia in adults with MDD. MDD is associated with a high prevalence of obstructive sleep apnea.	Evaluate and manage sleep disturbances to reduce risk of future depressive disorders. Provide advice on sleep preparation to improve sleep regularity and efficiency. This can benefit adults with MDD.
Stress and social connectedness (Table 7)	Loneliness and a lack of social connectedness increase the risk of MDD; MDD in adults is associated with a lack of a sense of belonging.	Assess adults with MDD for stress, loneliness, and social connectedness; recommend, as needed, relaxation (mind-body) and other stress management techniques and social interventions (peers, family, community).
Substances and the environment (Table 8)	Substance use, including cannabis, is associated with a higher prevalence of anxiety, depression, and suicidal ideation; lifestyle interventions can promote neuroplastic change and aid in substance use recovery.	Recognize that adults with MDD may use cannabis or other substances that can impair recovery, and that social determinants of health (e.g., food insecurity, homelessness) may impact the success of interventions.
Adherence to treatment and optimizing treatment (Table 9)	Lifestyle intervention is most effective in individuals who show readiness to change, have self-efficacy skills, have access to needed care and services, and have a good support system (peers, family, community).	Facilitate integrating lifestyle interventions into an individual’s daily activities (as opposed to discrete periods of time) and coordinate care across the interdisciplinary team to optimize lifestyle treatment for MDD. Provide psychotherapy and environmental interventions when needed.

CBT, cognitive behavioral therapy; DSM-5-TR, Diagnostic and Statistical Manual of Mental Disorders, 5^th Ed.; MDD, major depressive disorder; UPF, ultra-processed foods.

^aSpecial populations include those with psychological or external barriers (e.g., social determinants of health), psychological trauma (e.g., physical abuse), adverse childhood events, and women who are pregnant, postpartum, lactating, or peri/postmenopausal.

Disclaimer

Expert consensus statements are based on the opinions of carefully chosen content experts and provide for informational and educational purposes only. The purpose of the development group is to synthesize information, along with possible conflicting interpretations of the data, into clear and accurate answers to the question of interest. Expert consensus statements may reflect uncertainties, gaps in knowledge, opinions, or minority viewpoints, but through a consensus development process, many of the uncertainties are overcome, a consensual opinion is reached, and statements are formed. Expert consensus statements are not clinical practice guidelines and do not follow the same procedures as clinical practice guidelines. Expert consensus statements do not purport to be a legal standard of care. The responsible clinician, in light of all the circumstances presented by the individual patient, must determine the appropriate treatment, diagnosis, and management. Consideration of expert consensus statements will not ensure successful patient outcomes in every situation. The ACLM emphasizes that these clinical consensus statements should not be deemed to include all proper diagnosis/management/treatment decisions or methods of care or to exclude other treatment decisions or methods of care reasonably directed to obtaining the same results.

Supplemental Material

Supplemental Material - Lifestyle Interventions for Major Depressive Disorder (MDD): An Expert Consensus Statement From the American College of Lifestyle Medicine

Supplemental Material for Lifestyle Interventions for Major Depressive Disorder (MDD): An Expert Consensus Statement From the American College of Lifestyle Medicine by Gia Merlo, Steve Sugden, Richard M. Rosenfeld, David Baron, Micaela C. Karlsen, Sarah-Ann Keyes, John P. McHugh, Lawrence A. Miller, Charles B Nemeroff, Marie-Elizabeth Ramas, Kara L. Staffier, Kim A. Williams, Kathleen P. Wilson, William Wong, and Ramaswamy Viswanathan in American Journal of Lifestyle Medicine

Footnotes

Declaration of Conflicting Interests

The authors declared the following potential conflicts of interest with respect to the research, authorship, and/or publication of this article: GM receives royalties from Oxford University Press and Taylor & Francis for published books. KAS and MCK are employees of the American College of Lifestyle Medicine. RR receives consulting payments from the American College of Lifestyle Medicine. KPW is on the speaker bureau for Novo Nordisk (Diabetes). ER works for Aledade Inc. DB developed BDSA (depression screener for athletes, nonpaid). All other authors have no conflicts to disclose.

Funding

The author disclosed receipt of the following financial support for the research, authorship, and/or publication of this article: This work was supported by the American College of Lifestyle Medicine.

ORCID iDs

Gia Merlo

Steve Sugden

Richard M. Rosenfeld

Micaela C. Karlsen

Kara L. Staffier

Kim A. Williams

Supplemental Material

Supplemental material for this article is available online.

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