The most comprehensive controlled trial of diet and mood found that a plant-based diet significantly improved depression, anxiety, and productivity. Another study involving two diet intake groups found that the more plant-based group showed greater improvement in mood than the other group. A study of almost 300,000 Canadians found greater fruit and vegetable intake to be associated with lower risk of depression, distress, and self-reported mood or anxiety disorders.
Natural monoamine oxidase enzyme inhibitors in fruits and vegetables are one potential factor explaining the improvement in mood linked with a plant-based diet. The inclusion of plant foods with a high tryptophan to total protein ratio, such as seeds, is another possible factor. Animal food intake appears to reduce tryptophan levels in the brain, which in turn tends to worsen moods. The lack of arachidonic acid in plants, but its presence in animal foods, may also account for why plant-based diets may help in boosting overall mood. A plant-based diet can also reduce a type of inflammation associated with depression.
Athletes who undergo intense training may find that nutritional yeast after strenuous exercise may help them maintain both their energy and their overall mood. Saffron may help relieve PMS symptoms, including better regulation of mood swings. A study involving 21 Alzheimer’s disease patients found that while daily apple juice intake did not boost cognitive performance or day-to-day functioning, it did help with patients’ moods.
Researchers have found that individuals with mood disorders may be particularly sensitive to the artificial sweetener, aspartame. For people sensitive to wheat, short-term exposure to gluten appears to worsen their mood by inducing feelings of depression. For those dependent on caffeine, withdrawal symptoms can include mood disturbances. The spice, nutmeg, may boost mood but also can be toxic at a dose of just two teaspoons. A national study found that fish consumption does not appear to boost people’s moods. Due to possible serious side-effects, tryptophan supplements should not be used to try to improve mood.
Topic summary contributed by Linda.