- Fasting 2 days a week
People on the 5:2 diet eat normal amounts of healthy foods for 5 days and reduce their caloric intake on the other 2 days.
During the two-day fast, men typically consume 600 calories and women 500.
Generally, people separate the fasting days in the week. For example, they may fast on Monday and Thursday and eat normally on the other days. There must be at least one fasting day between fasting days.
The 5:2 diet, also known as the fasting diet, has been the subject of limited research. One reliable study of 107 overweight or obese women found that twice-weekly calorie restriction and continuous calorie restriction resulted in similar weight loss.
The study also found that the diet reduced insulin levels and improved insulin sensitivity in participants.
A small study by Trusted Source examined the effects of this fasting style in 23 overweight women. Over the course of a menstrual cycle, the women lost 4.8% of their body weight and 8.0% of their total body fat. However, these values returned to normal in most women after 5 days of normal dieting.