Check out this answer from Consensus:
The current body of research presents mixed findings on the effects of intermittent fasting on appetite. While a systematic review and meta-analysis found no significant impact on appetite compared to continuous energy restriction1, the use of appetite suppressants during fasting periods showed promise in reducing hunger2. Additionally, animal studies suggest that intermittent fasting induces hypothalamic changes that could lead to overeating during feeding periods but also result in lower body mass3. Further research is needed to fully understand the complex relationship between intermittent fasting and appetite regulation.
Intermittent fasting (IF) has gained popularity as a dietary strategy for weight management and metabolic health. One of the key questions surrounding IF is whether it helps to lower appetite, which could potentially make it easier for individuals to adhere to this eating pattern. This article explores the effects of intermittent fasting on appetite by reviewing recent research findings.
Effects of Intermittent Fasting on Appetite
Systematic Review and Meta-Analysis
A comprehensive systematic review and meta-analysis aimed to quantify the effects of intermittent fasting on appetite compared to continuous energy restriction interventions. The study included 17 randomized controlled trials with a total of 1111 participants. The findings indicated that intermittent fasting did not significantly affect hunger, fullness, desire to eat, or prospective food consumption when compared to continuous energy restriction1. This suggests that intermittent fasting may not mitigate the increase in appetite that often accompanies weight loss.
Appetite Suppressant Co-Therapy
Another study investigated the use of a bitter hops-based appetite suppressant (Amarasate®) during a 24-hour water-only fast. The study involved 30 adult men who fasted for 24 hours once a week for three weeks. The results showed that both high and low doses of the appetite suppressant significantly reduced hunger by more than 10% during the fasting period. Additionally, the expected increase in hunger around lunchtime was absent in the treatment groups2. These findings suggest that appetite suppressant co-therapy may be effective in reducing hunger during intermittent fasting.
Hypothalamic Modifications and Overeating
Research on male Sprague-Dawley rats revealed that intermittent fasting induces hypothalamic modifications, resulting in lower feeding efficiency, reduced body mass, and overeating during fed periods. The study found increased expression of orexigenic neurotransmitters AGRP and NPY in the hypothalamus, even on feeding days, which could explain the overeating pattern observed. These changes in hypothalamic function provide a mechanistic explanation for the lower efficiency of energy conversion and differences in body mass and caloric intake3. This suggests that while intermittent fasting may lead to overeating during feeding periods, it also results in overall lower body mass.
Does intermittent fasting help lower appetite?
Peter Rogers has answered Uncertain
An expert from Bristol University in Psychology, Nutrition
Fasting will increase appetite. With an empty stomach we are ready to eat and enjoy food again (we are ‘hungry’). However, people who fast intermittently, can adapt to its effects. They learn to find distractions and other ways to manage their appetite and they become less preoccupied with thoughts about eating.