If you're feeling particularly stressed at the moment, start eating more fish and walnuts - they may help stop you getting ill.
While we all know that stress can make us sick, we don't really know why that is. Psychologist Janice K Kiecolt-Glaser from the Ohio State University College of Medicine has done a review of the science, and suggests ways that stress and depression can make us ill.
When we're stressed or depressed, we produce more chemicals known as proinflammatory cytokines such as interleukin-6. While inflammation helps kill disease, too much can cause diseases such as arthritis, type II diabetes and Alzheimer's.
Some of the best anti-inflammatory foods are those rich in omega 3, such as fish and walnuts. So when you're feeling stressed or depressed, eat more of these and you'll counter the worst effects.
(Source: Perspectives on Psychological Science, 2009; 4: 367).