JAMA’s 2 state-of-the-art analyses: one on eating red meat and colon cancer (it appears causative); and the other on eating fruits and vegetables and breast cancer in midlife (they appear unrelated).

Why red meat and colon cancer? Maybe it’s the nitrosamines caused by heating, or the heterocyclic amines caused by charring. Maybe it’s the nitroso compounds in salami, bologna and sausage. Maybe it’s the iron in the meat. There are more theories. What counts is not the theory—but the major increased risk in migrant populations: a living experiment.

Could you reverse it? Yes! Are people with “good genes” probably exempt? Yes! Is enough known about your cancer risk and what you eat? For some cancers, yes. For others, not yet. But you can make yourself younger with what you eat.