A new study suggests that intermittent fasting can help with weight loss. Intermittent or alternate-day fasting consists of routinely alternating between eating small quantities of food or no food at all and then feasting in your daily diet.
Fasting has rapidly become one of the most sought-ought weight loss methods, and it has become a trend in the U.S., the UK and other countries in the world.
The study was published May 1 in the journal JAMA Internal Medicine and was conducted by scientists from University of Illinois, University of Alabama, Stanford University and the Pennington Biomedical Research Center.
Alternate fasting participants lost more weight than calorie-counting participants
The study found that there is no significant difference between intermittent fasting and other popular weight loss methods that restrict how many calories you consume in a day.
“We basically showed that they both produce a clinically significant amount of weight loss,” said Krista Varady, Professor of nutrition at the University of Illinois in Chicago and study’s lead author, according to CNN. “Instead of being better than calorie restriction, it’s the same.”
She added that alternate-day fasting it’s an alternative to calorie restriction. The researchers analyzed 100 obese adults in Chicago for the study, which was conducted between 2011 and 2015. The adults in the study were randomly assigned to three groups, and for one year, each group had to follow an alternate-day fasting diet, no diet at all or a calorie-restriction diet.
Participants in the alternate-fasting diet group could only eat around 25 percent of the calories that are suggested for a daily diet on a fasting day, which was about 500 calories, and then they fasted every other day. Fasting days were alternated with feasting days, in which participants could eat up to 125 percent of the recommended set of calories.
The US Dietary Guidelines currently estimate that adult women need between 1,600 and 2,400 calories per day, depending on their physical activity level. For adult men, they calculate a daily income of between 2,000 and 3,000 calories, depending on fitness level.
The group with calorie-restriction diets had to restrict their calorie intake to about 75 percent of what’s recommended per day. Participants in the fasting and calorie counting groups were given meals for the first three months of the research and then were on their own for the final nine months, according to Varady. They were provided with counseling throughout the year they were involved in the study. The groups were instructed on portion sizes and provided methods on how they could monitor their calorie intake and read food labels.
Varady said that by the end of the yearlong diet process, those in the alternate-day fasting group lost around 6 percent of their original body weight, while those in the restriction group only lost 5.3 percent weight.
Researchers believe that although both groups experienced similar weight loss, they found a higher percentage of members in the fasting group cheating on their diets compared to the restriction group.
Dropout rate in fasting group was alarming to researchers
The dropout rate in the intermittent fasting group was 37 percent, whereas in the daily calorie-restriction group 29 percent of participants dropped out.
“Even if the weight loss was a primary end point, I think that the question is really: What is the best strategy to get people to stick to a diet?” said Eric Ravussin, co-author of the study and professor at Louisiana State University’s Pennington Biomedical Research Center, according to CNN.
Ravussin stated that researchers understand daily calorie restriction, meaning, counting calories every day, can be tough to participants.He believes the alternate-fasting method would be a better strategy for people who want to lose weight, but the dropout rate is alarming to Ravussin. Varady even thought, before conducting the research, that alternate-day fasting would be an easier diet to stick to because it allowed for a “break” from dieting.
“We were a little bit shocked to see that it was actually the calorie-restriction group that seemed like they could stick better to their daily calorie goals. Whereas the alternate.day fasting group, they were kind of wavering,” said Varady, according to CNN.
She noted that instead of eating the 500 calories on the fasting days, the participants were eating a couple of hundred calories more on those days. The researchers concluded their study saying that alternate-day fasting does not produce superior weight loss compared to the calorie-restriction group.
Varady said she expects to conduct follow-up research to track the different diets over longer periods of time. She added that the team would like to explore whether allowing study participants to voluntarily opt to join either a calorie-restriction group or a fasting group might influence the research results.
Source: JAMA Internal Medicine