The most comprehensive controlled trial of diet and mood finds that a plant-based nutrition program in a workplace setting across ten corporate sites significantly improves depression, anxiety, and productivity.
Flashback Friday: Plant-Based Diets for Improved Mood and Productivity
A 2014 systematic review and meta-analysis of dietary patterns and depression concluded that a healthy diet pattern was significantly associated with reduced odds of depression, but out of the 21 studies they could find in the medical literature, they were able to find only one randomized controlled trial, considered the study design that provides the highest level of evidence. It was the study I profiled in Improving Mood Through Diet, in which removing meat, fish, poultry and eggs improved several mood scores in just two weeks.
We’ve known that those eating plant-based tend to have healthier mood states—less tension, anxiety, depression, anger, hostility, and fatigue. But you couldn’t tell if it was cause and effect until you put it to the test, which they finally did. What could account for such rapid results? Well, eating vegetarian does give you a better antioxidant status, which may help with depression.
Also, as I’ve previously addressed, consumption of even a single carbohydrate-rich meal can improve depression, tension, anger, confusion, sadness, fatigue, alertness, and calmness scores among patients with PMS—but what about long term?
Overweight men and women were randomized into a low-carb, high-fat diet, or high-carb, low-fat diet for a year. By the end of the year, who had less depression, anxiety, anger, and hostility, feelings of dejection, tension, fatigue, better vigor, less confusion, or mood disturbances? The low-carb dieters are represented by the black circles, and the low-fat dieters are represented in the white. These sustained improvements in mood in the low-fat group compared with the low-carb group are consistent with results from epidemiological studies showing that diets high in carbohydrate and low in fat and protein are associated with lower levels of anxiety and depression, and have beneficial effects on psychological wellbeing.
But the overall amount of fat in their diet didn’t significantly change in this study, though. But the type of fat did. Their arachidonic acid intake fell to zero.
Arachidonic acid is an inflammatory omega-6 fatty acid that can adversely impact mental health via a cascade of neuroinflammation. It may inflame your brain. High blood levels in the bloodstream have been associated with a greater likelihood of suicide risk, for example, and major depressive episodes. How can we stay away from the stuff?
Americans are exposed to arachidonic acid primarily through chicken and eggs. But when we remove chicken and eggs, and other meat, we can eliminate preformed arachidonic acid from our diet.
So, while high-quality treatment studies investigating the impact of diet on depression are scarce, there is that successful two-week trial, but even better, how about 22 weeks?
Overweight or diabetic employees of a major insurance corporation received either weekly group instruction on a whole food plant-based diet or no diet instruction for five and a half months. There was no portion size restriction, no calorie counting, no carb counting. No change in exercise. No meals were provided, but the company cafeteria did start offering daily options such as lentil soup, minestrone, and bean burritos.
No meat, eggs, dairy, oil, or junk, yet they reported greater diet satisfaction compared with the control group participants who had no diet restrictions. How’d they do though? More participants in the plant-based intervention group reported improved digestion, increased energy, and better sleep than usual at week 22 compared with the control group. They also reported a significant increase in physical functioning, general health, vitality, and mental health. Here’s that represented graphically, where the plant-based group beat out controls on nearly every measure.
There were also significant improvements in work productivity, thought to be due, in large part, to their improvements in health. So, what this study demonstrated was that a cholesterol-free diet is acceptable, not only in research settings, but in a typical corporate environment, improving quality of life and productivity at little cost. All we need now is a large, randomized trial for confirmation, but we didn’t have such a thing—until now.
Ten corporate sites across the country from San Diego to Macon, Georgia. Same kind of setup as before. Can a plant-based nutrition program in a multicenter, corporate setting improve depression, anxiety, and productivity? Yes, significant improvements in depression, anxiety, fatigue, emotional well-being, and daily functioning. Lifestyle interventions have an increasingly apparent role in physical and mental health, and among the most effective of these is the use of plant-based diets.
To see any graphs, charts, graphics, images, and quotes to which Dr. Greger may be referring, watch the above video. This is just an approximation of the audio contributed by Katie Schloer.
Please consider volunteering to help out on the site.
- A L Lopresti, S D Hood, P D Drummond. A review of lifestyle factors that contribute to important pathways associated with major depression: diet, sleep and exercise. J Affect Disord. 2013 May 15;148(1):12-27.
- U Agarwal, S Mishra, J Xu, S Levin, J Gonzales, N D Barnard. A multicenter randomized controlled trial of a nutrition intervention program in a multiethnic adult population in the corporate setting reduces depression and anxiety and improves quality of life: the GEICO study. Am J Health Promot. 2015 Mar-Apr;29(4):245-54.
- J S Lai, S Hiles, A Bisquera, A J Hure, M McEvoy. A systematic review and meta-analysis of dietary patterns and depression in community-dwelling adults. Am J Clin Nutr. 2014 Jan;99(1):181-97.
- Y T Szeto, T C Kwok, I F Benzie. Effects of a long-term vegetarian diet on biomarkers of antioxidant status and cardiovascular disease risk. Nutrition. 2004 Oct;20(10):863-6.
- H I Katcher, H R Ferdowsian, V J Hoover, J L Cohen, N D Barnard. A worksite vegan nutrition program is well-accepted and improves health-related quality of life and work productivity. Ann Nutr Metab. 2010;56(4):245-52. doi: 10.1159/000288281. Epub 2010 Apr 14.
- G D Brinkworth, J D BUchley, M Noakes, P M Clifton, C J Wilson. Long-term effects of a very low-carbohydrate diet and a low-fat diet on mood and cognitive function. Arch Intern Med. 2009 Nov 9;169(20):1873-80.
- B L Beezhold, C S Johnston. Restriction of meat, fish, and poultry in omnivores improves mood: a pilot randomized controlled trial. Nutr J. 2012 Feb 14;11:9.
- J J Wurtman, A Brzezinski, R J Wurtman, B Laferrere. Effect of nutrient intake on premenstrual depression. Am J Obstet Gynecol. 1989 Nov;161(5):1228-34.
- A A Farooqui, L A Horrocks, T Farooqui. Modulation of inflammation in brain: a matter of fat. J Neurochem. 2007 May;101(3):577-99.
- B L Beezhold, C S Johnston, D R Daigle. Vegetarian diets are associated with healthy mood states: a cross-sectional study in seventh day adventist adults. Nutr J. 2010 Jun 1;9:26.
- J S Vaz, G Kac, A E Nardi, J R Hibbein. Omega-6 fatty acids and greater likelihood of suicide risk and major depression in early pregnancy. J Affect Disord. 2014 Jan;152-154:76-82.
Images thanks to JD Hancock via Flickr.
A 2014 systematic review and meta-analysis of dietary patterns and depression concluded that a healthy diet pattern was significantly associated with reduced odds of depression, but out of the 21 studies they could find in the medical literature, they were able to find only one randomized controlled trial, considered the study design that provides the highest level of evidence. It was the study I profiled in Improving Mood Through Diet, in which removing meat, fish, poultry and eggs improved several mood scores in just two weeks.
We’ve known that those eating plant-based tend to have healthier mood states—less tension, anxiety, depression, anger, hostility, and fatigue. But you couldn’t tell if it was cause and effect until you put it to the test, which they finally did. What could account for such rapid results? Well, eating vegetarian does give you a better antioxidant status, which may help with depression.
Also, as I’ve previously addressed, consumption of even a single carbohydrate-rich meal can improve depression, tension, anger, confusion, sadness, fatigue, alertness, and calmness scores among patients with PMS—but what about long term?
Overweight men and women were randomized into a low-carb, high-fat diet, or high-carb, low-fat diet for a year. By the end of the year, who had less depression, anxiety, anger, and hostility, feelings of dejection, tension, fatigue, better vigor, less confusion, or mood disturbances? The low-carb dieters are represented by the black circles, and the low-fat dieters are represented in the white. These sustained improvements in mood in the low-fat group compared with the low-carb group are consistent with results from epidemiological studies showing that diets high in carbohydrate and low in fat and protein are associated with lower levels of anxiety and depression, and have beneficial effects on psychological wellbeing.
But the overall amount of fat in their diet didn’t significantly change in this study, though. But the type of fat did. Their arachidonic acid intake fell to zero.
Arachidonic acid is an inflammatory omega-6 fatty acid that can adversely impact mental health via a cascade of neuroinflammation. It may inflame your brain. High blood levels in the bloodstream have been associated with a greater likelihood of suicide risk, for example, and major depressive episodes. How can we stay away from the stuff?
Americans are exposed to arachidonic acid primarily through chicken and eggs. But when we remove chicken and eggs, and other meat, we can eliminate preformed arachidonic acid from our diet.
So, while high-quality treatment studies investigating the impact of diet on depression are scarce, there is that successful two-week trial, but even better, how about 22 weeks?
Overweight or diabetic employees of a major insurance corporation received either weekly group instruction on a whole food plant-based diet or no diet instruction for five and a half months. There was no portion size restriction, no calorie counting, no carb counting. No change in exercise. No meals were provided, but the company cafeteria did start offering daily options such as lentil soup, minestrone, and bean burritos.
No meat, eggs, dairy, oil, or junk, yet they reported greater diet satisfaction compared with the control group participants who had no diet restrictions. How’d they do though? More participants in the plant-based intervention group reported improved digestion, increased energy, and better sleep than usual at week 22 compared with the control group. They also reported a significant increase in physical functioning, general health, vitality, and mental health. Here’s that represented graphically, where the plant-based group beat out controls on nearly every measure.
There were also significant improvements in work productivity, thought to be due, in large part, to their improvements in health. So, what this study demonstrated was that a cholesterol-free diet is acceptable, not only in research settings, but in a typical corporate environment, improving quality of life and productivity at little cost. All we need now is a large, randomized trial for confirmation, but we didn’t have such a thing—until now.
Ten corporate sites across the country from San Diego to Macon, Georgia. Same kind of setup as before. Can a plant-based nutrition program in a multicenter, corporate setting improve depression, anxiety, and productivity? Yes, significant improvements in depression, anxiety, fatigue, emotional well-being, and daily functioning. Lifestyle interventions have an increasingly apparent role in physical and mental health, and among the most effective of these is the use of plant-based diets.
To see any graphs, charts, graphics, images, and quotes to which Dr. Greger may be referring, watch the above video. This is just an approximation of the audio contributed by Katie Schloer.
Please consider volunteering to help out on the site.
- A L Lopresti, S D Hood, P D Drummond. A review of lifestyle factors that contribute to important pathways associated with major depression: diet, sleep and exercise. J Affect Disord. 2013 May 15;148(1):12-27.
- U Agarwal, S Mishra, J Xu, S Levin, J Gonzales, N D Barnard. A multicenter randomized controlled trial of a nutrition intervention program in a multiethnic adult population in the corporate setting reduces depression and anxiety and improves quality of life: the GEICO study. Am J Health Promot. 2015 Mar-Apr;29(4):245-54.
- J S Lai, S Hiles, A Bisquera, A J Hure, M McEvoy. A systematic review and meta-analysis of dietary patterns and depression in community-dwelling adults. Am J Clin Nutr. 2014 Jan;99(1):181-97.
- Y T Szeto, T C Kwok, I F Benzie. Effects of a long-term vegetarian diet on biomarkers of antioxidant status and cardiovascular disease risk. Nutrition. 2004 Oct;20(10):863-6.
- H I Katcher, H R Ferdowsian, V J Hoover, J L Cohen, N D Barnard. A worksite vegan nutrition program is well-accepted and improves health-related quality of life and work productivity. Ann Nutr Metab. 2010;56(4):245-52. doi: 10.1159/000288281. Epub 2010 Apr 14.
- G D Brinkworth, J D BUchley, M Noakes, P M Clifton, C J Wilson. Long-term effects of a very low-carbohydrate diet and a low-fat diet on mood and cognitive function. Arch Intern Med. 2009 Nov 9;169(20):1873-80.
- B L Beezhold, C S Johnston. Restriction of meat, fish, and poultry in omnivores improves mood: a pilot randomized controlled trial. Nutr J. 2012 Feb 14;11:9.
- J J Wurtman, A Brzezinski, R J Wurtman, B Laferrere. Effect of nutrient intake on premenstrual depression. Am J Obstet Gynecol. 1989 Nov;161(5):1228-34.
- A A Farooqui, L A Horrocks, T Farooqui. Modulation of inflammation in brain: a matter of fat. J Neurochem. 2007 May;101(3):577-99.
- B L Beezhold, C S Johnston, D R Daigle. Vegetarian diets are associated with healthy mood states: a cross-sectional study in seventh day adventist adults. Nutr J. 2010 Jun 1;9:26.
- J S Vaz, G Kac, A E Nardi, J R Hibbein. Omega-6 fatty acids and greater likelihood of suicide risk and major depression in early pregnancy. J Affect Disord. 2014 Jan;152-154:76-82.
Images thanks to JD Hancock via Flickr.
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Flashback Friday: Plant-Based Diets for Improved Mood and Productivity
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Content URLDoctor's Note
Here’s the link for the video I mentioned about the original randomized controlled trial, Improving Mood Through Diet, and the pilot data on workplace interventions can be found in Slimming the Gecko and Plant-Based Workplace Intervention.
Diet can help at home too! See:
- Fighting the Blues with Greens?
- Exercise vs. Drugs for Depression
- Do Antidepressant Drugs Really Work?
- Antioxidants and Depression
- Can Dehydration Affect Our Mood?
- Anti-inflammatory Diet for Depression
- Fish Consumption and Suicide
- Which Foods Increase Happiness?
- Are Happier People Actually Healthier?
- Benefits of Blueberries for Mood and Mobility
Arachidonic what? For background on the inflammatory fatty acid see:
- Inflammatory Remarks About Arachidonic Acid
- Chicken, Eggs, and Inflammation
- Chicken’s Fate Is Sealed
2019 Update: I just did a new series on the CHIP program. Check it out:
- What Is the Optimal Diet?
- The Weight Loss Program that Got Better with Time
- CHIP: the Complete Health Improvement Program
- A Workplace Wellness Program that Works
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