Three recent studies document that consumption of processed foods increase odds of depression, and not only that, but those high protein, high fat diets (high in animal products) are also linked with more depression. The diet to protect against depression – that is simple, a high nutrient, plant-based diet outlined in my books, Eat for Health and Eat to Live.
In one study, middle-aged subjects were categorized by their dietary patterns based on how much “whole” or “processed” food they consumed. The high processed foods group was characterized by high intake of sweetened desserts, fried food, processed meat, refined grains, and high-fat dairy products. Five years later, the researchers evaluated how many of the subjects had reported depression symptoms.
Subjects who ate the most whole foods had the lowest odds of depression, and those who ate the most processed foods had the highest odds of depression – 60% increased odds compared to those who ate the least amount of processed foods.1
Another study compared the effects of low-fat plant-based diet and low-carbohydrate animal-product-rich diet on mood in overweight women. Although both groups lost similar amounts of weight over one year, measures of mental health and mood only improved in the low-fat group. The low-carb dieters eating more fat and animal products had higher depression scores. The authors also cited previous human studies in which high protein, low-carbohydrate diets have resulted in cognitive impairment.2
A third study measured scores of depression before and after removing meat, poultry, and fish from subjects normally eating a typical American diet. Indicators of depression significantly decreased after removing all the animal products and shifting to a plant-based diet for 2 weeks. 3
Nutrition is crucial for regulating mood – high oxidative stress in the brain and low levels of several micronutrients have also been linked to depression.4
These studies are a reminder that what we eat affects not only our physical health but our mental health as well. Combine great diet with light therapy, exercise, sufficient Vitamin D and the right fatty acid balance for the brain, and you have my protocol to beat depression.
1. Akbaraly TN et al. Dietary pattern and depressive symptoms in middle age. Br J Psychiatry. 2009 Nov;195(5):408-13.
2. Brinkworth et al. Long-term Effects of a Very Low-Carbohydrate Diet
and a Low-Fat Diet on Mood and Cognitive Function. Arch Intern Med. 2009;169(20):1873-1880
3. Beezhold BL et al. Preliminary evidence that vegetarian diet improves mood. American Public Health Association 2009 National Meeting, Abstract 206464.
4. Leung BM, Kaplan BJ. Perinatal depression: prevalence, risks, and the nutrition link--a review of the literature. J Am Diet Assoc. 2009 Sep;109(9):1566-75.