According to a study done at the University of Alabama in Huntsville, vitamin C can alleviate the body’s response to stress. The study tested the effects of it on the adrenal function of laboratory animals subjected to stress.
The adrenal glands react to stress by releasing hormones that trigger the “fight or flight” response. Suppression of the immune system is one of the adrenal hormones’ response to stress.
Stress was created in the rats by immobilizing them for one hour each day. Some of the rats were supplemented, others were not. The rats that were fed vitamin C produced lower levels of adrenal stress hormones. Other stress indicators, like enlargement of the adrenal glands and shrinking of the thymus gland and spleen were not as pronounced in those rats. The vitamin C also increased levels of IgG (an antibody that defends against infection. The IgG levels were also higher in the control group (rats that were not stressed).
Other studies have demonstrated the role of vitamin C in improving the immune system. It improved immune function in a test group of elderly women. It also reduced the incidence of stress-related upper-respiratory infections in marathon runners.