Is alternate-day fasting more effective for losing and maintaining weight compared with a daily diet that simply limits calorie intake? Findings of a new study have revealed that while fasting diets are on trend these days, they are no better than traditional calorie-restricted diet when it comes to weight loss.
Alternate-Day Fasting
In a new study published in JAMA Internal Medicine on May 1, Eric Ravussin, from Louisiana State University's Pennington Biomedical Research Center, and colleagues took a closer look at the relative effectiveness of the alternate-day fasting weight loss method in which a person drastically reduces his or her calorie intake every other day but eat more than usual on so-called non-fasting days.
Beyoncé and Benedict Cumberbatch are just among the celebrities whose diets are known to be based on intermittent fasting.
Alternate- Day Fasting Not Significantly Better Than Traditional Diet
Ravussin and colleagues found that intermittent fasting is not significantly better compared with diet that restricts intake of calories per day for people who want to lose weight or maintain weight.
Participants in the traditional diet group and the fasting group lost an average of about 7 percent more of their body weight than those who did not go on a diet after six months. After a year, participants in the first two group lost 5 to 6 percent of their initial body weight.
The results show that there is no significant difference between traditional method of losing weight and alternate-day fasting.
"Alternate-day fasting has been promoted as a potentially superior alternative to daily calorie restriction under the assumption that it is easier to restrict calories every other day. However, our data from food records, doubly labeled water, and regular weigh-ins indicate that this assumption is not the case," the researchers wrote in their study.
In the study, those in the alternate-day fasting group consumed 25 percent of their normal calories intake on fasting days but 125 percent of their normal calorie intake on non-fasting days. Those in the traditional diet group, on the other hand, consumed 75 percent of their normal calorie intake daily.
Study Dropouts
Researchers also found that it is not easy to change people's eating habits. A large percentage of the participants who were asked to fast for the study did not follow the requirements and even dropped out of the study.
In comparison, 38 percent of those in the fasting group dropped out prior to the one-year mark of the study because they were not satisfied with their diet, while only 29 percent of those in the traditional diet group did.
"We know daily calorie restriction — if you have to count your calories every day and all that — it's a tough one. I think that there's some hope that this alternate-day fast, or modified fast, would be a better or easier strategy, but ... the dropout rate is kind of alarming," Ravussin said.
Researchers also found that participants in the fasting group tend to cheat on their fasting days by eating more than they should.