Mental Health and the Magic of Antioxidants
Updated: Feb 22
In this video I read from Dr. Greger's book titled 'How Not to Die' in a chapter that's titled 'How Not to Die from Suicidal Depression' on pages 208-9.
Main Points:
A nationwide American study measured the level of carotenoid phytonutrients in people's bloodstreams and found that the higher levels of phytonutrients the less likely one suffered from depression and/or other mental illnesses.
Antioxidant pills in supplement form do not seem to work.
People with low levels of folate seem to have nearly a threefold increase of experiencing depression.
Excerpt (as read in video above):
Accumulating evidence suggests that free radicals -- those highly unstable molecules that cause tissue damage and contribute to aging -- may play an important role in the development of various psychiatric disorders, including depression. Modern imaging techniques confirm autopsy studies showing a shrinkage of certain emotion centers in the brain of depressed patients that may be due to death of nerve cells and these areas caused by free radicals.
This phenomenon may help explain why those who eat more fruits and vegetables which are rich in the antioxidants that extinguish free radicals appear protected against depression. A study of nearly 300,000 Canadians found that greater fruit and vegetable consumption was associated with lower risk of depression, psychological distress, mood and anxiety disorders and poor perceive mental health. The researchers concluded that eating antioxidant-rich plant foods "may dampen the detrimental effects of oxidative stress on mental health."
The Canadian study relied on questionnaires asking people to self-report fruit and vegetable intake, a method that's not always accurate. A nationwide American study took it one step further and measured the level of carotenoid phytonutrients in people's bloodstreams. These phytonutrients include some of the yellow, orange, and red antioxidant pigments found naturally in some of our healthiest foods, including sweet potatoes and gravy lean vegetables. Not only did people with higher levels of nutrients in their bloodstreams have a lower risk of depression symptoms but there was also an apparent "dose response relationship," meaning that the higher level of phytonutrients the better people seem to feel.
Among the carotenoids, lycopene, (the red pigment in tomatoes) has the highest antioxidant activity. Indeed, a study of nearly 1000 elderly men and women found that people who ate tomatoes or tomato products daily had just half the odds of depression compared with those who ate them once a week or less.
If antioxidants are so helpful, why can't we just pop a few antioxidant pills? Well, only food sources of antioxidants appear to be protectively associated with depression. The same cannot be said for dietary supplements. The finding may indicate that the form and delivery of the antioxidants we consume are crucial to ensure their best effects. Alternatively, antioxidants may just be a marker for other components of plant-rich diet such as folate.
Folate is a B vitamin concentrated in beans and greens. (Its name comes from the Latin word folium, meaning "leaf" because it was first isolated in spinach.) Early studies linking depression to low folate levels in the blood were cross sectional in nature, meaning they were only snapshots in time. For this reason, we didn't know whether low folate intake led to depression or if depression led to low folate intake. However, more recent studies following people over time suggest that low dietary folate intake may indeed increase the risk of severe depression by as much as threefold. However, once again, folate supplements (folic acid) do not appear to help.
Vegetables -- including antioxidant-rich tomatoes and fully packed greens -- may be good for the body and the mind.
End of Excerpt
