Yes, you have to anticipate it, because once you've got it, you're already in serious trouble. Cancer cells thrive in much the same way as your other cells making them hard to target. So the time to fight it is yesterday.

Chris Hoy has just reported a cancer diagnosis. As a cyclist, he would have expended HUGE amounts of energy and consumed HUGE amounts of food for fuel. If he has since had a more sedentry life-style without moderating his food intake in proportion, it probably made a big contribution to his getting cancer. The Hairy Bikers' Dave Myers recently died of cancer. The duo often commented on how fat they were.

The main life-style contributing factors are: Smoking, Excess Eating (7.6%), Booze (5.4%), UV (4.6%), Inactivity (3.1%).

Get that? The second biggest risk-factor is over-eating, something they don't mention very much.

In other words, smoking, booze and UV cause damage. Excess eating and inactivity support the cancer cells.

There is one feature, however, that makes cancer cells vulnerable and that's their inability to use ketones for fuel; they need glucose.

When carbohydrates are consumed they produce glucose. When fats are consumed, you get ketones. Protein apparently gets converted to carbohydrates too ("In Defense of Carbs").

However, an even better way to fight cancer is fasting. About 18hrs after your last meal, you've finished digesting food. Your pancreas reduces insulin and your liver starts burning body-fat for fuel, producing ketones, whilst blood glucose levels reduce. Damaged cells tend to die off because they need glucose and are then recycled to offset the fall in blood glucose.