With so many different diets and eating tips floating around, it can be hard to know what actually works and what ends up doing more harm than good. Intermittent fasting is one of the popular options at the moment, however, new research suggests that it could be undoing all the hard work you’ve been putting in at the gym.
For those who aren’t familiar with the diet, which was voted the hottest diet of 2020 by Forbes (opens in new tab), it’s all about giving yourself a select window for eating. This can be flexible but it typically means you can’t eat for an extended period of time, which could be for 12 or 16 hours in a day.
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Usually, this means you’ll skip breakfast and have your first meal around lunchtime, then have an eight hour window to eat before fasting for the next 16 hours. This is known as the 16:8 and is one of the most popular intermittent fasting options. However, new research suggests that it may not be the best option for those trying to bulk up and build muscle.
The diet means you’ll be skipping breakfast which ultimately ends in muscle loss, according to a study by Ethan J. Weiss, MD, a cardiologist and associate professor at the Cardiovascular Research Institute at the University of California.
Dr. Weiss, whose research was published in JAMA Internal Medicine (opens in new tab) in December 1029, conducted his study by getting 116 overweight or obese adult participants into one of two groups. Half of them were told to eat three meals per day, with snacks allowed, between 7 am and 11pm, meanwhile the other group was on a 16:8 plan, where they ate as much as they wanted from midday to 8pm, then fasted until 12pm the next day.
At the end of the study, Dr. Weiss found that there wasn’t a big difference between the intermittent fasting group and the control group, especially in terms of weight loss. Most surprisingly of all, the results showed that most of the weight loss in the intermittent fasting group was “lean mass” which is muscle rather than fat. On top of that, the study also concluded that there weren’t any significant differences between groups when it came to health, including things such as blood pressure, triglyceride levels, total cholesterol levels, fasting glucose levels, or insulin levels.
“This form [of intermittent fasting] as it is, without calorie restriction or a different diet, does not appear to work,” said Dr. Weiss. “Lots more research needs to be done here.” Interesting!