Is it okay to fast only during 8hours each 24h?

It is generally acceptable to have an 8-hour feeding window within a 24-hour period as part of time-restricted feeding or intermittent fasting. Andrew Huberman discusses that there is nothing inherently special about an 8-hour feeding window, but it was originally used for research convenience 1. The key advantage of time-restricted feeding lies in aligning the feeding window with the active phase of one's day, usually during daylight hours, to avoid eating during the nocturnal phase, which is detrimental to health 1.

Consistency is important in maintaining the beneficial effects of time-restricted feeding. This means trying to keep the feeding window consistent each day to help with regulating essential clock genes, which play roles in metabolic health 2. Shifting eating windows frequently, for instance, due to weekend schedules, may disrupt circadian rhythms and reduce health benefits 3.

In addition to the timing, the quality and quantity of food consumed during the feeding window are also crucial for achieving health benefits 4. While time-restricted feeding can be a convenient way to manage calorie intake, the overall number of calories and food quality remain critical for health outcomes 5.