A recent study by neuroscientists Matthew During and Lei Cao from Ohio State and Cornell University suggests that living in a stimulating environment may help prevent cancer. The team studied two sets of young male mice: one group was housed in a standard cage with nothing but food, while the other group was placed in a large cage with food, toys, a maze, running wheels, and places to hide. After 3-6 weeks in the cages, the researchers injected both sets of mice with melanoma cancer cells and found that the mice who lived in the enriched cage for 3 weeks had 43% smaller tumors, the mice who lived in the enriched cage for 6 weeks had 77% smaller tumors, and a few of those from the enriched cages developed no tumors at all. The researchers also found that exercise alone was not enough to explain the test results, as mice raised in a standard cage with a running wheel grew tumors just as large those that did no exercise. During believes that the anticancer effects may be related to metabolic changes, such as lower blood levels of leptin, higher levels of corticosterone, and higher levels of brain-derived neurotrophic factor, all of which suggest that living a life with slight stress may be more healthy than one with no stress at all.