The Effects of Intermittent Fasting on Metabolism: A Review of the Evidence

A dietary pattern known as intermittent fasting involves times of voluntarily abstention from food and liquids, followed by intervals of regular eating. Alternate-day fasting, periodic fasting, and time-restricted feeding are a few methods of intermittent fasting. While intermittent fasting has become more popular in recent years as a weight management method, it may also improve insulin sensitivity, lower oxidative stress, and improve heart health markers.

Through its influence on hormones like insulin and ghrelin, intermittent fasting may affect metabolism in one or more ways. In reaction to eating, the hormone insulin is released, which controls blood sugar levels. It has been demonstrated that intermittent fasting lowers insulin levels and enhances insulin sensitivity, which may improve the body’s utilization of glucose and promote weight loss. The “hunger hormone,” also referred to as ghrelin, controls appetite and energy intake. Ghrelin levels may rise as a result of intermittent fasting, which could speed up metabolism and raise energy expenditure.

Through its effects on weight loss, intermittent fasting may also have an impact on metabolism. Intermittent fasting has been linked to weight loss in several studies, which may be partially explained by how it affects metabolism. Researchers discovered that intermittent fasting was linked to a 3-8% decrease in body weight over the course of 3–24 weeks in one review of 12 studies. It’s crucial to remember that other aspects, such as nutrition quality and physical exercise, can also affect weight loss.

It’s also important to keep in mind that people who are overweight or obese may respond to intermittent fasting differently than people who are at a healthy weight. According to some studies, those who are overweight or obese might gain more advantages from intermittent fasting than people who are at a healthy weight in terms of weight loss and increases in insulin sensitivity. For instance, a research in the journal Obesity found that compared to obese women who followed a calorie-restricted diet, those who followed an intermittent fasting diet for 16 weeks lost much more weight and improved their insulin sensitivity.

As a result of its impact on hormones like ghrelin and insulin, as well as its ability to aid in weight loss, intermittent fasting may influence metabolism. When compared to people who are at a normal weight, the effects of intermittent fasting on metabolism may vary for those who are overweight or obese. It’s vital to note that other factors like meal quality and physical activity may also impact metabolism in order to completely appreciate the effects of intermittent fasting on metabolism.


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  • Varady, K. A., Bhutani, S., Klempel, M. C., Kroeger, C. M., Trepanowski, J. F., & Haus, J. M. (2013). Alternate day fasting for weight loss in normal weight and overweight subjects: a randomized controlled trial. Nutrition Journal, 12, 146.
  • Halberg, N., Henriksen, M., Söderhamn, N., Stallknecht, B., Ploug, T., Schjerling, P., & Dela, F. (2005). Effect of intermittent fasting and refeeding on insulin action in healthy men. Journal of Applied Physiology, 99(6), 2

One thought on “The Effects of Intermittent Fasting on Metabolism: A Review of the Evidence

  1. Love my IF lifestyle. I’m down 45lbs and now off all my prescriptions! Taking the Reset electrolyte fasting capsules has really helped!

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