Intermittent Fasting

Eating a very low calorie diet of around 25% of normal intake (500 calories for women, 600 for men) on one or two days a week and eating normally on the other days has been shown to (a) lower cholesterol, (b) lower blood pressure, (c) improve insulin sensitivity and (d) stimulates the brain and body to go into repair mode, and may potentially guard against degenerative brain diseases.

The 5:2 eating plan is based on intermittent fasting. On two (non-consecutive) days a week you eat only the low calorie diet of 500 / 600 calories while on the other days you eat normally. Restricting calorie intake does not  result in eating excessive amounts on the following day, while the long periods between eating are what stimulate the body to go into repair mode. In order to feel reasonably full on a calorie restricted day, foodstuffs are typically vegetables (high fibre, low calorie) and a small amount of protein.