The Physicians Committee

Foods that Fight Depression

  February 27, 2015    

This is a guest post from Ulka Agarwal, M.D.

As a psychiatrist, my patients often ask me if there are dietary changes they can make to improve their depression. Many cannot tolerate antidepressants, don’t benefit from them, or are reluctant to try medications or seek counseling due to stigma. As a result, they miss an average of 19 work days per year, costing employers up to $44 billion dollars a year in lost productivity. Depression can aggravate other chronic illnesses as well, like diabetes and heart disease. We know that plant-based diets prevent and even treat these chronic illnesses, but can they also improve mood? Our recent study published in the March/April issue of the American Journal of Health Promotion demonstrates how a plant-based nutrition program improves not only depression, but anxiety, fatigue, productivity, and other markers of well-being.

This 18-week study analyzes the health benefits of adopting a plant-based vegan diet in a corporate setting. Study participants, GEICO employees who were either overweight or struggling with type 2 diabetes, adopted a low-fat vegan diet, favoring high-fiber, low-glycemic foods. They learned about preventive nutrition and new cooking tips through weekly “lunch and learn” sessions led by a clinician or cooking instructor. They also formed bonds, sharing helpful health tips along the way and connecting with the group on a daily basis through an online forum. Study participants alleviated symptoms of anxiety, depression, and fatigue, and improved their productivity both at work and outside of work, according to the 36-Item Short Form Health Survey (SF-36) and the Work Productivity and Activity Impairment Questionnaire (WPAI):

ulka blog graphic

They also lost an average of 10 pounds, lowered LDL cholesterol levels by 13 points, and improved blood sugar control, if they had type 2 diabetes. When people improve their physical health they become more physically and socially active and their overall quality of life improves.

How does a plant-based diet improve depression? Depression is related to inflammation in the body and low levels of serotonin. Plant-based foods naturally lower inflammation in the body because they are naturally low in fat and high in antioxidants. High vegetable intake increases the amount of B vitamins in the diet, which have been found to affect mood.

So what are you waiting for? Jump right in with a low-fat, plant-based diet! It’s the best prescription to boost your mood, energy, and productivity, while reducing your risk for chronic illnesses. I know I’ll be prescribing a plant-based diet to all of my patients for their emotional and physical well-being. To learn more about the study, visit the American Journal of Health Promotion

About Ulka Agarwal, M.D.

Ulka Agarwal, M.D., is the lead physician and psychiatrist at California State University, East Bay, where she developed and leads a plant-based employee wellness nutrition program.  Dr. Agarwal is the former chief medical officer for the Physicians Committee and a graduate of Dr. Andrew Weil’s Integrative Medicine Fellowship through the University of Arizona.


Dr. Agarwal: Congratulations on what looks to be a excellent contribution to the scientific literature (my library doesn't have the March/April issue of AJHP yet).
Did you by any chance enroll many cigarette smokers and if so was there a difference in quit rates between the intervention and control group?
I am beginning to study whether nutritional factors might influence nicotine addiction and smoking initiation and cessation.
Thanks in advance for considering this request.
Kind regards,
Gary Giovino

Great question. We did not track tobacco use quit rates in this study. This is such an important area of research, I look forward to seeing your results! All the best.

My fasting blood sugar is around 90-110 mg/dl, and I'm pretty darn sure I'm insulin resistant. I just ate a pulpy fruit and veggie smoothie (5 bananas, an apple, an orange, a cantaloupe, two handfuls of kale, two handfuls of spinach, a cucumber, and 4 sticks of celery.

After one hour (usually the peak of blood sugar) I poked my finger and checked my blood sugar -- it was 184 mg/dl!!

This really worries me.

I have been eating veggies, some fish, and almonds and walnuts (low carb, moderate protein, high-ish fat) for about a week and decided to give this high-carb thing a shot because I'm about 35 pounds overfat.

These blood sugar numbers are not normal!

Are you telling me that a high-carb (natural fruit sugars), low-fat diet is gonna fix this post-meal blood suagr spike, when all it seems to do is make my blood sugar worse??




I like this student study on plant-based diet and depression.

Great information. Very good study you have done. Thanks for sharing this well detailed information with us.

Can I have the name of this study? I'd like to use it for a research paper.

A question

I am a Vegan psychologist, so I am very interested about these types of studies... I wonder if the improvement in mood can be a consequence of partecipating in a support group, learning new ways of cooking food, taking care of oneself and loosing weight as opposed to the benefit of the plant based diet by itself... partecipants were either overweight or diagnosed with diabetes, are there any other studies with "normal" population and control groups?


Hi, I am doing a study into the possible link between veganism and depression for my final year uni project, and I am hoping to interview a Vegan Psychologist. would you be interested in partaking in my studies? And if so could I get your contact email please?


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