Intermittent fasting may seem like it’s all the rage, especially with the rise of the 5:2 diet, which urges people to eat normally for five days a week, and then restrict calories to 500-600 for the following two days. But new research suggests these trendy eating plans may also have damaging side effects.

A new study out of the University of São Paulo in Brazil found that risk for long-term health issues like diabetes may be increased as a result of frequent fasting. Researchers analyzed rats who were only fed every other day. While the rodents lost weight, the amount of fat around their tummies increased. The insulin-secreting cells of their pancreases also showed damage and there was also an increase of free radicals. All of these warning signs are often early warning signs of diabetes. This conflicts with previous studies which claims fasting can provide a host of health benefits. So maybe the jury is still out?

Ana Bonassa, whose team led the research, had this to say, “This is the first study to show that, despite weight loss, intermittent fasting diets may actually damage the pancreas and affect insulin function in normal healthy individuals, which could lead to diabetes and serious health issues.” The scientists also advise that those considering fasting diets should exercise caution before opting to more extreme eating habits.

While the fasting that took place in the study was more extreme than some diets recommend (and was also conducted on rats), it’s still notable for its findings. If anything, it suggests further research needs to be done to fully examine the impact of low caloric intake on pancreas function and insulin production, especially in those with existing metabolic issues.

In the meantime, don’t deprive yourself. Just stick to eating in moderation and getting plenty of exercise? It may not sound sexy, but in terms of health and weight loss, it’s hard to argue with.

Header image courtesy of Shutterstock.

Jessica is a former Associate Editor at Chowhound. Follow her on Twitter @volume_knob for updates on snacks and cats.
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