For people searching for ways to lose weight and improve their health, there is mixed evidence on the best strategies to make it happen. A new study by U of U Health scientists finds that intermittent fasting, a weight loss approach that has been gaining attention, may have a beneficial impact on several health measures under certain circumstances.
"This study shows the beneficial associations of intermittent fasting on obesity-related health outcomes that were supported by moderate to high-quality evidence," says the study's senior author Nathorn Chaiyakunapruk, PharmD, PhD, a professor in the Department of Pharmacotherapy at U of U Health.
His team reviewed studies summarizing clinical trials to gauge the health impacts of alternating periods of fasting and eating on a regular schedule throughout the week. They found that intermittent fasting seems to be most beneficial for people who are overweight or obese. The approach was associated with improvements in a number of obesity-related health outcomes, including body mass index, body weight, lipid profile, and glycemic profile.
Chaiyakunapruk points out that the body responds to this weight loss strategy differently than it does to popular diets. "Intermittent fasting focuses not only on total quality of food consumed but also when food is consumed," he says.
He explains that periods of fasting trigger a "metabolic switch" where the body temporarily shifts from burning sugars to burning body fat. It also stimulates responses in the body's cells, including boosting cell repair and dampening inflammation. That, in turn, improves metabolic health, at least temporarily.
Due to limitations of the clinical trials, it is not known how long any of the associated benefits last or if intermittent fasting has any harmful effects over the long term. Additional studies will need to be done to determine whether the benefits reported in the study improve overall health over a lifetime, for example, by reducing the risk for heart disease, cancer, or diabetes.
Although the initial results sound encouraging, more needs to be learned, and intermittent fasting is not for everyone. Before giving it a try, Chaiyakunapruk recommends consulting with your health care provider.