Many people have recently become interested in intermittent fasting, fasting, and fasting-mimicking diets. Fasting and fasting-mimicking, in particular, may not be for everyone, but early research shows some potential benefits.
According to research, fasting and diets that mimic fasting can benefit the immune system and may reduce markers associated with age-related disease.
Fasting-mimicking diets occur over the course of five days per month, completed once every four months. The diet is low in calories, sugars, and protein, is moderate in carbohydrates, and high in unsaturated fats. After the five days, an individual’s regular eating patterns are resumed.
Fasting and fasting-mimicking diets activate a process in the body called autophagy. Autophagy is a process of cell renewal and regeneration, in which damaged cells in the body are replaced with younger and more effective immune cells. One small randomized trial demonstrated that cycles of five days of a fasting-mimicking diet per month for 3 months reduced risk factors for age-related diseases. Individuals on the fasting-mimicking diet had reduced body weight, total body fat, fasting glucose, blood pressure, and other markers associated with aging and age-related disease.
What to eat on these diets will depend on an individual’s personal situation and age. For adults, the food eaten is mostly vegan, including fish two to three times per week. For those under 65 years, protein intake should remain around 0.31-0.36 grams per pound of body weight. Protein is kept low because it can activate the mTOR pathway, a signaling pathway that plays a role in cell proliferation and growth. Reducing protein can turn off this pathway, which is thought to be beneficial. The main source of protein comes from beans, chickpeas, green peas, and other legumes. Saturated fat and sugar are minimized while whole grains, quality vegetables, olive oil, and nuts should be emphasized. Eating should occur within a 12 hour period.
The benefits of fasting-mimicking diets on autophagy and immunity seem promising. However, fasting-mimicking diets are not for everyone. The restrictive cycle may be triggering for some individuals and can encourage disordered eating behaviors. This diet is also not ideal for those who are pregnant or breastfeeding. As research is still developing, fasting-mimicking should only be undertaken under the supervision of a licensed healthcare professional.
