I am reading a great book by Daniel Amen M.D., of TED talk fame, called Change Your Brain Change Your Body.
Quote from book:
"Numerous studies have shown that when unrelenting stress hits, it causes many of us to look for solace in [high fat meals]. Unfortunately, high-fat foods can also trigger stressful reactions. Researchers at University of Calgary examined stress reactions in two groups of students. The first group ate a high-fat breakfast while the second group noshed on a low-fat meal. Two hours later, the stress subjects went through a series of stressful tasks. In each of the tasks, the group that gorged on the high-fat meal showed higher stress reactions than the second group."
Quote from website:
"according to the National Safety Council, stress causes as much as 80% of all disease and illness."
-Daniel Amen M.D.
The website and excellent video on stress and your brain:
high fat vegan though?