In the spirit of the season, Paul Davis, PhD, of the University of California, Davis, and colleagues in the laboratory discovered that whole walnuts or walnut oil may slow prostate cancer growth. The team administered walnut derivatives to transgenic adenocarcinoma of the mouse prostate (TRAMP) mice and identified a significant reduction in prostate tumor size, likely due to the fat component of walnuts. "For years, the United States government has been on a crusade against fat, and I think it's been to our detriment," said Dr. Davis, who published the team's work in the Journal of Medicinal Food, in a news release from the University. "Walnuts are a perfect example. While they are high in fat, their fat does not drive prostate cancer growth. In fact, walnuts do just the opposite when fed to mice". Adding to the benefits, walnuts reduced cholesterol levels and increased insulin sensitivity in the TRAMP mice, as well as reducing the levels of insulin-like growth factor (IGF)-1, shown to play a role in prostate cancer. "The energy effects from decreasing IGF-1 seem to muck up the works so the cancer can't grow as fast as it normally would,"