Stress and aggression have biological link

A recent animal study may help expain why some people become easily enraged and find it difficult to calm down. In the study, behavioral neurosceintists found a feedback loop between stress hormones and the aggression control centers in their brains. Since the neurophysiology of rats is similar to humans, this biological link may explain, for example, the link between traffic jams (stress) and road rage (aggression). The study also suggests that stress and aggression are mutually reinforcing; higher levels of stress hormone created a response in the brain’s aggression mechanism, and stimulating the aggression mechanisms raised stress hormone levels.
Insulin therapy may increase risk of colorectal cancer.

People with type 2 diabetes who take insulin may have a greater risk of colorectal cancer. Previous studies have suggested a link between diabetes and colorectal cancer; this study specifically examines whether insulin therapy promotes cancer of the colon or rectum. Researchers found that chronic insulin elevation significantly increases the risk of colorectal cancer in people with type 2 diabetes. Additionally, the longer the treatment, the greater the risk: those who received insulin for three years or more had three times the risk of developing colorectal cancer. Re-searchers suggest that insulin itself stimulates the growth of cancer cells.