by Terry Correll, DO; Julie Gentile, MD, MBA; and Andrew B. Correll, MD

Dr. T. Correll is Clinical Professor, Department of Psychiatry, Wright State University Boonshoft School of Medicine in Dayton, Ohio. Dr. A. Correll is with Wright State University Boonshoft School of Medicine in Dayton, Ohio. Dr. Gentile is with the Department of Psychiatry at Wright State University in Dayton, Ohio. 

FUNDING: No funding was provided for this article.

DISCLOSURES: The authors declare no conflicts of interest relevant to the content of this article.

Innov Clin Neurosci. 2025;22(1–3):20–27.

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Department Editor

Julie P. Gentile, MD, MBA is Professor and Chair of the Department of Psychiatry at Wright State University in Dayton, Ohio.

Editor’s Note

The patient scenarios presented in this article are composite cases written to illustrate certain diagnostic characteristics and to instruct on treatment techniques. The composite cases are not real patients in treatment. Any resemblance to real patients is purely coincidental. 

Abstract

Healthy lifestyle and positive psychiatry interventions can complement the treatment of mood disorders and help individuals who are not experiencing as much happiness and satisfaction in their lives as they desire. This article gives examples of an optimal psychiatric treatment plan that would potentially include psychotherapy, psychotropic medications, and/or individualized and targeted healthy lifestyle and positive psychiatry interventions to not only treat mental illness, but also enhance overall wellbeing.

Keywords: Positive psychiatry, positive psychology, healthy lifestyle interventions, happiness, lifestyle psychiatry, lifestyle medicine

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Healthy lifestyle interventions and positive psychiatry are two complementary approaches that can synergistically improve mood and overall mental health. Positive psychiatry has been defined as “the science and practice of psychiatry that seeks to understand and promote wellbeing through assessment and interventions aimed at enhancing behavioral and mental wellness.”¹ Positive psychiatry is closely related to positive psychology, which emphasizes the use of evidence-based techniques such as gratitude, mindfulness, and learned optimism, and is a branch of psychiatry that focuses on improving overall wellbeing and mental health rather than solely alleviating mental illness and misery. Lifestyle medicine is a new paradigm that shifts much of the responsibility to the patient and can be defined as “the use of evidence-based lifestyle therapeutic approaches, such as a predominately whole food, plant-based diet, physical activity, sleep, stress management, tobacco cessation, and other nondrug modalities to prevent, treat, and, oftentimes, reverse the lifestyle-related chronic disease that’s all too prevalent.”² See Figure 1² for a summary of key takeaways for lifestyle medicine and Box 1¹ for a summary of key takeaways for positive psychiatry. There is growing evidence that these lifestyle interventions can be effective treatments for common mental illnesses,³ with little-to-no adverse effects and the added benefit of reducing the risk of other chronic nonpsychiatric conditions, such as metabolic syndrome (58% more likely in those with a psychiatric illness).⁴ This manuscript provides examples of how evidence-based lifestyle medicine and positive psychiatry interventions can be administered along with psychotherapy and psychopharmacology for an optimal treatment plan that fosters an overall increase in happiness and wellbeing.

 

Clinical Case Vignette 1

A 54-year-old woman, D, presented for an initial psychiatric evaluation. With the COVID-19 pandemic and loss of socialization, she had a gradual onset of depressive symptoms that included increased consumption of comfort foods (eg, rocky road ice cream) with an accompanying weight gain of 19lbs, sleeping for an average of 11 hours per night, lack of enjoyment in normally pleasurable activities, low energy levels, feelings of being discounted by others, heavy and immobile limbs at least once a week upon awakening, and associated psychomotor slowing. 

Psychiatrist: When do you typically feel at your best?

D: I guess when good things happen to me, but it is hard to keep the positivity going. Over the three years of the pandemic, I felt generally happy for as long as about a year. That was when business was hopping at my accounting firm and I was in a solid relationship. Everything came crashing down, though, when my rotten boyfriend left me at the beginning of this year, and, ever since, my mood has been crappy. I do look forward to my Friday nights where I pick horses at the local raceway, but the rush of winning doesn’t last long.

Psychiatrist: How has your sleep been lately?

D: It’s been hard for me to get out of bed, and I’ve been sleeping more than usual. When I wake up, my arms and legs feel like heavy weights, and it’s difficult for me to get out of bed and start my day.

Psychiatrist: You mentioned earlier that you have been gaining weight. Tell me more if you don’t mind.

D: I have been packing on the pounds! I think I am reaching for more comfort foods because I just don’t have the energy to search out healthier food options. It takes a lot of work to go to the store, check out, take the groceries home, and maintain fresh food in my refrigerator.

Psychiatrist: What kind of emotions do you feel most often?

D: Sadness and numbness, I guess. I also easily get frustrated at and sensitive to what other people say about me. 

Practice Point 1

Having the word “atypical” in the name does not mean that atypical depression is rare, as about 15.3 percent of those diagnosed with major depressive disorder (MDD) have atypical symptoms, according to a study of 1,172 patients in China.⁵ Like our patient, the hallmarks of atypical depression—hypersomnia, increased appetite, leaden paralysis, and rejection sensitivity—are more common in women compared to men.^5–7 MDD without atypical features, on the contrary, typically results in weight loss and insomnia. D has periods of an hour or so upon awakening when her arms and legs feel very heavy, which is consistent with leaden paralysis, a symptom that can occur in up to 72.5 percent of those with atypical depression.⁸ 

D also mentioned that she liked to pick horses at the racetrack, and gambling is a risk factor for depression.^9,10 D’s short-lived pleasant feelings related to winnings in gambling and easy frustration are consistent with mood reactivity, a key distinguishing characteristic between atypical and typical depression.¹¹ Interestingly, research shows that depression seems to attenuate emotional reactions to positive stimuli (d=–0.53) more than potentiate reactions to negative stimuli (d=–0.25).¹² 

Clinical Case Vignette 1, Continued

Psychiatrist: Are there any fruits and vegetables that you enjoy eating? I am asking because studies show that just eating two more servings of fruits and/or vegetables per day can increase your feeling of wellbeing.¹³ 

D: Vegetables don’t sound so appealing right now, but I do like fruits.

Psychiatrist: That’s great. Can we focus on you getting two servings of various fruits each day until our next appointment? How does that sound?

D: Wow, I’ve never received a food prescription before! But I’m all for it—bring on the fruit!

Practice Point 2

The dietary recommendation in the clinical case is based on a randomized, controlled trial of 171 participants that found that an additional two servings of fruits and/or vegetables for 14 days was correlated with significant increases in psychological wellbeing.¹³ Two servings of fruits and/or vegetables is likely achievable by most patients and is thus a reasonable and easy “win” as a recommendation. Practically, the additional servings of healthy food would likely displace less healthy options that would otherwise be consumed. The SMILES trial found significantly reduced Montgomery–Åsberg Depression Rating Scale (MADRS) depression scores after a 12-week dietary intervention that emphasized whole grains, fruits, vegetables, and legumes.¹⁴ There is evidence to suggest that nutritional interventions might be particularly effective in treating depression. A meta-analysis of 16 trials found a beneficial effect (g=0.162) on depression, but no such statistically similar result for anxiety,¹⁵ while another meta-analysis found that individuals who followed a healthy diet including fish, fruit, legumes, pulses, nuts, seeds, vegetables, and whole grains had a decreased risk of depression.¹⁶ This type of diet is similar to the Mediterranean diet, which has been shown to reduce symptoms of depression compared to a Western diet,¹⁷ sometimes referred to as a standard American diet. 

There are several potential mechanisms through which healthy eating can improve mood. These include the modification of neurotransmitters, reduction of oxidative stress, promotion of neurotrophic factors, regulation of the hypothalamic-pituitary-adrenal axis, and improvement of mitochondrial function.¹⁸ There are higher rates of inflammatory markers, such as erythrocyte sedimentation rate, in individuals with depression.¹⁹ Also, interferon-induced inflammation in the treatment of hepatitis has been linked to increased depression risk.²⁰ Processed foods and meat seem to cause more inflammation from toll-like receptors on monocytes than do fruits and vegetables.²¹ Inflammatory arachidonic acid is also not found in plant-derived foods.²² 

Flavonoids and polyphenols are highly anti-inflammatory²³ and are found most concentrated in colorful fruits and vegetables, such as oranges, strawberries, and broccoli.²⁴ Flavonoid intake associated with adherence to the Mediterranean diet is associated with fewer depressive symptoms²⁵ and increased cognitive performance and brain-derived neurotrophic factor (BDNF).²⁶ BDNF is a neurotrophic molecule that has protective effects on depression and anxiety and is increased by antidepressant treatment.^27,28 A review found that polyphenol intake associated with the consumption of colorful fruits and vegetables was the most strongly associated with increases in BDNF among various food intake patterns.²⁹ 

Clinical Pearls

• If a patient enjoys a particular healthy food or practice, it might be wise to capitalize on that and encourage any small victories. A journey of a thousand miles begins with a few steps.
• Following the patient’s preferences increases the potential for adherence. By respecting and following the preferences of patients, the psychiatrist not only demonstrates that they care about the patient’s distinctive needs and desires, but also increases the likelihood the patient will adhere to the treatment recommendations.
• Moving toward whole and less-processed foods is optimal for overall physical and mental health.
• Easy-to-prepare, whole-food, plant-based grocery store options that can be introduced to patients include prepared salads, fresh fruit and vegetables, dry-roasted nuts, canned beans and healthy soups, old-fashioned oats, walnuts, and frozen fruit and vegetables. Microwavable frozen edamame and quinoa might also be easy suggestions to make.
• Preference for salt tends to decrease over time with healthier diets, and flavor intensity experienced tends to be higher in those with healthier diets.³⁰
• Help patients discover new, flavorful ways to add whole grains, fruits, and vegetables into their diet by suggesting recipes or pairing less flavorful foods (eg, plain oatmeal) with more flavorful ingredients (eg, berries, nuts, or cinnamon).
• Consider the patient’s cultural and religious preferences, and try to tailor recommendations to the individual patient.
• Being mindful of how much information to share can help prevent recommendations from becoming overly daunting. Start small and gradually increase the focus on healthy eating
• Any movement toward a healthier lifestyle, small as it might be, is a win.

Clinical Case Vignette 2

A 34-year-old male patient, H, presented for a follow-up psychiatric appointment with the goal of managing his sertraline 50mg daily, which was initiated three months ago for persistent depressive disorder (PDD). He has previously been diagnosed with borderline personality disorder (BPD) as well. At the start of the conversation, H indicated that although he had experienced significant improvement in his depressive symptoms, he remained on the lookout for ways to enhance his happiness and was seeking further knowledge on how to achieve this.

H: Thank you so much for helping me feel better lately. Don’t get me wrong, I am not bursting with joy, but things are definitely on the upswing. I hear people talk about being happy all the time, but I’m not sure what that means, as I have never really felt that way.

Psychiatrist: We will discuss likely increasing your dose of sertraline today, but I wonder how possible it is to feel good all the time.

H: It sure would be nice!

Psychiatrist: Yes, indeed. Some people who deal with a lot of adversity are actually very happy.

H: I know a few people like that.

Psychiatrist: They likely rely on healthy coping mechanisms to deal with their difficulties. What are some healthy ways by which you handle the storms of life?

H: I think I try to maintain a lighthearted attitude toward things so that they don’t seem as serious. I remember one time we were hiking as a group and it started raining, and everyone was wet, cold, and miserable, but I tried making jokes and we laughed about it the whole way to the car. Laugh at your problems, I say, because everyone else does.

Psychiatrist: What a great story, and I totally agree that you have a great sense of humor and a way of framing things that happen to you in a healthy perspective. Happiness is not necessarily about feeling good all the time, but about learning how to productively deal with the bad times and savoring the good times.

H: That reminds me of that Victor Frankl book. Have you read that one? The one where the man in the concentration camp was still happy even with all that was going on?

Psychiatrist: That is a great analogy. What stood out to you about that book?

Practice Point 3

H presented with a preexisting diagnosis of PDD with pure dysthymic syndrome, characterized by two or more years of depressed mood for most of the day and for more days than not.³¹ It has a prevalence of about 0.5 to 1.5 percent in the general population and is about twice as common in female individuals, compared to male individuals.³² H was also diagnosed with BPD in the past, which is a significant risk factor for PDD.³³ H’s objective was not only to relieve his depression, but to enhance his sense of happiness and overall wellbeing as well. To achieve this goal, positive psychiatry can be utilized, which concentrates more on protective factors and less on risk factors.¹ Positive psychiatry is closely aligned with positive psychology, which Martin Seligman called “a reoriented science that emphasizes the understanding and building of the most positive qualities of an individual.”³⁴ It is within the realm of the psychiatrist with psychotherapy skills to explore ways to learn from the “negatives” in life and enhance the “positives.”

If H is happier, he is more likely to use his humor and lightheartedness as coping mechanisms.^35,36 Humor and lightheartedness can serve as a barometer of the patient’s overall wellbeing, as humor is considered to be one of our most mature and healthy defense mechanisms. The psychiatrist should actively promote the happiness of patients because happy people are also more likely to have healthier lifestyles.³⁷ Reported happiness is associated with lower levels of stress³⁸ and higher levels of self-esteem and life satisfaction.³⁹ This can lead to a potential snowballing of benefits, since exercise, healthy eating, and healthy sleep can lead to positive mental health outcomes.^40,41

How can one practically increase happiness? Research suggests a person’s chronic happiness level is approximately 50-percent controlled by a genetically determined set point, about 10-percent controlled by happiness-related circumstances (e.g., winning the lottery), and about 40-percent controlled by happiness-related activities and practices.⁴² This leaves a lot of room for H to potentially modify his happiness through intentional positive activities, such as learning to be more optimistic, performing acts of kindness, and practicing gratitude—all activities that have demonstrated statistically increased overall happiness measures in studies.^43,44

Clinical Pearls

• If a patient enjoys humor, try judicious use of humor yourself during sessions. This used to be discouraged for psychotherapy,⁴⁵ but has since been explored more,⁴⁶ and recent data suggests humor can be associated with improved outcomes when utilized appropriately.⁴⁷
• If a patient has a favorite book, you can attempt to establish a therapeutic dialogue related to the book and extract valuable insights from it. Any book that interests the patient can be utilized as bibliotherapy, which has therapeutic benefit in anxiety and depression.⁴⁸ There were no differences in therapeutic benefit between bibliotherapy and psychotherapy groups at three-month follow-up evaluation in a study of 31 individuals.^49,50 The authors find that allowing the patient to select the reading material is preferred and can be most helpful.
• Patients who don’t enjoy reading can access audio books or online video lecture presentations of their choice.

Clinical Case Vignette 2, Continued

Psychiatrist: So, let’s think of some practical things to focus on until our next visit. Do you like writing or journaling?

H: Yeah, I do tons of it. I have a cool app on my phone for journaling.

Psychiatrist: Perfect, what do you think about making a list of things that go well for you or that you are thankful or grateful for in that app until we meet again in a month?

H: Okay, how often do you think I should do that? 

Psychiatrist: What would work best for you?

H: Maybe once per week?

Psychiatrist: Great. Is there anything that you do every weekend that you can connect to this habit so that it’s more likely that you remember to do it?

H: I go to temple every Saturday, so I can try and remember to make a list before I head out the front door.

Psychiatrist: That could help make it more a part of your routine. Would it be okay to review some things from your list next time?

Practice Point 4

Gratitude can be defined as the “pleasant response of thankfulness after recognizing benefits received”⁵¹ and is a profound human emotion. Gratitude interventions, which involve expressing gratitude or reflecting on things one is grateful for, can have modest but helpful effects on depression and anxiety.^52,53 These interventions can be utilized as initial or adjunct treatments, as they have rapid effects within two weeks,⁵⁴ which might be comparable to and/or faster than the effects of antidepressants.^55,56 Gratitude practices can potentially buffer insecurely attached individuals in life from low relationship satisfaction and commitment.⁵⁷ Such gratitude practices can spread feelings of gratitude⁵⁸ to others and might enhance the relationships H has troubles with in the context of his BPD. 

In the vignette, the psychiatrist gave a choice for how often the patient wanted to record his feelings of gratitude. This is wise because it gives autonomy to the patient, and evidence suggests a variety of frequencies might be effective. For example, one study that asked participants to count their blessings one time per week led to more improvement in happiness than doing the same three times per week.⁴² However, other studies have found that writing down gratitude lists each day for 14 days can improve happiness⁵⁴ and that twice-weekly gratitude writing is effective for improving life satisfaction⁵⁹ and reducing stress levels.⁶⁰ Remind patients not to “guilt” themselves if they do not meet their predetermined writing cadence.

Journaling about anything can increase feelings of self-efficacy,⁶¹ and specifically writing about stressful events can allow one to focus on the positive aspects of those events.⁶² This kind of reframing has been described as “learned optimism” by psychologist Martin Seligman,⁶³ which suggests that individuals can cultivate an optimistic outlook in life by changing their naturally-occurring pessimistic thought patterns. The “Best Possible Self” intervention is well-studied⁶⁴ and improves optimism most significantly relative to other interventions.⁶⁵ One such study with 54 participants had one group write down all aspects of their future ideal self (Best Possible Self) and visualize this concept at home for five minutes per day. After two weeks, optimism scores were significantly increased, compared to the control group.⁶⁶ Challenging negative self-talk and reframing negative events as temporary rather than permanent can also help foster a resilient outlook in life. Gratitude journaling, in particular, seems to increase positive affect,⁶⁷ particularly when framed as a prayer.⁶⁸ Higher baseline religiosity may also predict increased gratitude.⁶⁹ 

Clinical Pearls

• There are great journaling apps that can allow individuals to effortlessly dictate reflections, reducing the friction and time expenditure of typing. Some people prefer to dictate over typing since people can dictate nearly four times as fast as they can type (198 words per minute⁷⁰ vs. 52 words per minute⁷¹).
• Linking a healthy habit to an existing routine, such putting on one’s shoes, can make it easier to implement. Habits are learned processes that trigger automatic responses,⁷² so contexts that cue healthy behaviors motivate change.
• Event-based cues seem to be more powerful than time-based ones;⁷³ an example of a cue for a gratitude practice could be when one’s head touches the pillow at night,⁷⁴ as a sense of gratitude can improve sleep quality.⁷⁵ 
• Encouraging the pursuit of hobbies that bring joy and fulfillment—particularly if those hobbies are centered around groups of people who come together due to the activity—can be extremely helpful for patients who want to improve their mood.
• Helping patients identify and manage negative thought patterns and behaviors is something that a psychotherapist can uniquely assist with to help improve mood.

Clinical Case Vignette 2, Continued

H: Well, you mentioned happiness, which is important to me. Not only for myself, but also for my family. (sighs) I wish my wife and I could get better jobs so we could buy our kids some nicer toys. Maybe they would smile more then.

Psychiatrist: Why do you think the toys might make your children happier?

H: I feel like I see some of our friends buying their kids toys that we just can’t afford. When I volunteer at toy distributions with Red Cross during the holidays, all the kids seem so happy when I give them gifts. I just wish I could do the same for my own kids.

Practice Point 5

Research suggests that happiness is less situational and more about how individuals respond to life’s circumstances.⁷⁶ It is important not to jump to conclusions about H’s desire to buy more toys for his children, but a materialistic focus has been demonstrated to be negatively correlated with happiness.^77,78 Money might “buy” happiness more so at lower income levels, but not as much beyond a level of basic sufficiency,⁷⁹ and overall the correlation between money and happiness is remarkably weak.⁸⁰ 

If the discussion were reframed to focus on how H could improve his relationships with his family members, something strongly correlated to happiness,^81–83 then there could be a more helpful therapeutic outcome for H. Individuals in happy relationships tend to report a higher level of subjective wellbeing.⁸³ This could bolster his resilience and potentially reinforce the positive response to sertraline that he had already received. The decision comes down to whether to work more for toy money or spend more time with his family, and studies show people who choose extra time instead of additional cash tend to be happier people.⁸⁴ Therefore, encouraging patients to capitalize on experiences rather than material items might be wise, as experiences tend to promote longer-lasting happiness levels.⁸⁵ Let’s see how a conversation like this might play out.

Clinical Case Vignette 2, Continued

Psychiatrist: It seems to me you are saying that if you buy your kids more toys to play with in their free time, they might have better lives. Is that what you are thinking?

H: Yeah, I just want to do the best that I can for them because they mean the world to me.

Psychiatrist: I think that your selfless intent to give something nice to your children is very admirable. Studies find that people generally feel better giving something than receiving.⁸⁶ What do you feel like when you serve at the Red Cross and at your temple?

H: When I volunteer, I feel alive and pumped up afterward. Part of it is that I want to set an example for my kids one day on how to give back.

Psychiatrist: Have you considered involving your family in the giving process and maybe letting them serve with you? Perhaps you could all contribute to serving those in need? This could teach your children the values you hold about helping others, and it could be a way for you to spend time together instead of working more at your job. What are your thoughts about that?

H: Hmm, thanks, that is an interesting idea. The more I think about it, the more I like it. It’s like the golden rule, “Do unto others as you would have them do unto you.” Maybe the same effort and time I would spend trying to earn more money might be better spent doing free things, like going to the park with my kids. There is a playground near my house they absolutely love going to, and when I push them on the swings, they get a kick out of that.

Psychiatrist: Compared to giving them toys, spending time at the park and volunteering together might not just help your kids feel happier, but almost certainly would make you feel better as well.

Practice Point 6

In the United States, approximately 24.9 percent of individuals volunteer for an organization at least once per year.⁸⁷ Numerous studies have shown that volunteering is correlated with increased life satisfaction, greater happiness, and reduced symptoms of depression.^88–91 Regular volunteering has a positive association on wellbeing that increases over time with continued volunteering,⁹² although it remains unclear whether happier individuals are more likely to volunteer or if volunteering itself contributes to increased happiness.⁹¹ Either way, volunteering can be a useful tool for monitoring a patient’s progress in treatment or as a potential treatment in its own right. The benefits of volunteering might stem from generating empathetic feelings within individuals and shifting their focus toward those who are less fortunate than themselves.⁹³ If physicians are interested in incorporating lifestyle medicine principles into their own practices, see Box 2 for some practical suggestions to get started.²

Conclusion

Positive psychiatry strategies used wisely in combination with healthy lifestyle interventions (lifestyle psychiatry)⁹⁴ can provide an important augmentation to traditional psychiatric treatments to optimize the overall treatment plan. This can be likened to adding more tools to the therapist’s toolbox. The consumption of healthy fruits and vegetables increases flavonoid and polyphenol intake and might help those with depression by reducing inflammation and increasing BDNF levels. Happiness and wellbeing can be a fertile topic for psychotherapy and lead to many avenues to bolster resilience through such interventions as bibliotherapy, journaling about life experiences, or recording feelings of gratitude. Discussion topics in therapy can reinforce the development of learned optimism and how relationships and volunteering might increase happiness. These interventions focus on building up the metaphorical walls of the patient to help them weather the storms of life more effectively, be more resilient overall, and hopefully live happier and healthier lives.

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