With alternate day fasting, what is the typical energy intake on fasting days?

In alternate day fasting, individuals typically consume about 25% of their usual energy needs on fasting days. This approach allows for a significant caloric deficit while still providing enough energy to mitigate extreme hunger and maintain metabolic functions. This percentage is generally sufficient to support essential bodily functions without providing enough energy to prevent the effects of fasting, such as fat oxidation and potential weight loss.

The 25% intake is designed to create a balance between fasting and non-fasting days, where on non-fasting days, individuals consume their normal caloric intake. This method has gained popularity for its flexibility compared to traditional calorie restriction, allowing individuals to still enjoy regular eating patterns on non-fasting days, thus potentially improving adherence to the overall dietary strategy.

This practice of consuming about 25% of energy needs on fasting days has been supported by various studies that indicate it can lead to favorable health outcomes, including weight loss and improvements in metabolic markers without leading to excessive hunger or energy deprivation.