Time-restricted Eating for the Prevention and Management of Metabolic Diseases

Abstract

Time-restricted feeding (TRF, animal-based studies) and time-restricted eating (TRE, humans) are an emerging behavioral intervention approach based on the understanding of the role of circadian rhythms in physiology and metabolism. In this approach, all calorie intake is restricted within a consistent interval of less than 12 hours without overtly attempting to reduce calories. This article will summarize the origin of TRF/TRE starting with concept of circadian rhythms and the role of chronic circadian rhythm disruption in increasing the risk for chronic metabolic diseases. Circadian rhythms are usually perceived as the sleep-wake cycle and dependent rhythms arising from the central nervous system. However, the recent discovery of circadian rhythms in peripheral organs and the plasticity of these rhythms in response to changes in nutrition availability raised the possibility that adopting a consistent daily short window of feeding can sustain robust circadian rhythm. Preclinical animal studies have demonstrated proof of concept and identified potential mechanisms driving TRF-related benefits. Pilot human intervention studies have reported promising results in reducing the risk for obesity, diabetes, and cardiovascular diseases. Epidemiological studies have indicated that maintaining a consistent long overnight fast, which is similar to TRE, can significantly reduce risks for chronic diseases. Despite these early successes, more clinical and mechanistic studies are needed to implement TRE alone or as adjuvant lifestyle intervention for the prevention and management of chronic metabolic diseases.

Keywords: Circadian rhythm; Intermittent fasting; Metabolic disease Metabolism; Time-restricted eating; Time-restricted feeding.

Graphical Abstract

Figure 1.

A schematic of ideal time-restricted eating (TRE) intervention for long-term adherence by incorporating the optimal sleep time and duration relative to TRE interval. Because bright light is known to inhibit the production and secretion of sleep promoting hormone melatonin, it is desirable to avoid bright light for 2 to 3 hours before habitual bedtime to promote better sleep. Adequate sleep is known to reduce food craving, which can support adherence to TRE. Since melatonin can potentially attenuate glucose-induced insulin release from the pancreas, avoiding food before bedtime immediately after wake up may further accentuate the TRE benefit on glucose regulation. The eating interval of 10 hours is illustrated as an example.

Figure 2.

Summary of various metabolic and other chronic diseases or risk factors that respond favorably to time-restricted feeding (TRF) or time-restricted eating (TRE) in animal models (rodents and Drosophila) or in humans. For simplicity, the green portion of the wheel represents the eating window and the gray portion represents the fasting window.