The effect of fasting or calorie restriction on autophagy induction: A review of the literature

Summary

This is the most-cited review of whether fasting and calorie restriction actually trigger autophagy — the cellular self-cleaning process that recycles damaged proteins and organelles. The authors surveyed studies across cell culture, rodent models, and human subjects, looking at autophagy markers such as LC3 lipidation, p62 turnover, ATG7 expression, and mTOR signalling under various fasting and calorie-restriction protocols. Their headline conclusion is that fasting and calorie restriction reliably upregulate autophagy across a wide variety of tissues and organs — liver, muscle, brain, heart, kidney — and that the effect is robust. They also note that autophagy is mechanistically central to the longevity and disease-prevention benefits of caloric restriction: blocking autophagy in animal models attenuates those benefits. The evidence base, however, leans heavily on rodent and cell-culture work; direct measurement of autophagy in living humans is limited because most autophagy markers require tissue biopsy.