In the past decade, the popularity of the “5:2 diet” has spread, altering the eating patterns of thousands of people seeking weight loss.
The 5:2 diet is an example of what’s called intermittent fasting or time-limited eating.
In its simplest form, the 5:2 diet means you can eat whatever you want five days a week (trying to continue to eat sensibly on those days), while on the other two days of the week you restrict your calorie intake drastically, often to Only about 500 calories.
While some research suggests that intermittent fasting is no better than a traditional diet for long-term weight loss, other types of trials point to important benefits associated with time-restricted eating — including health benefits from fasting that may go beyond diet.
Now, a new study led by researchers from Queen Mary University of London in the UK has identified another reason why some people might want to consider the 5:2 diet over other approaches.
In what the researchers claimed was “the first randomized evaluation of the 5:2 diet,” the team studied 300 obese adults, each of whom were randomly assigned to one of three different types of weight loss intervention.
In the experiment, 100 participants (a third of the entire group) received traditional weight management advice in one session with a counselor, who provided written materials explaining things like portion control, keeping a food diary, and instructions on how to avoid unnecessary snacks.
Another group of 100 participants (called a self-help group) had a different session, where they were advised on how to follow the 5:2 diet during the experiment, and were given a leaflet explaining meal examples, with links to additional online support, but were left to try the system feed on their own without significant additional assistance.
The last 100 participants received similar advice and documentation on how to follow the 5:2 diet, but were also enrolled in a series of six-week group support sessions, which were intended to help them discuss their experiences with the diet with others, ask the counselors questions, and what till then.
These three groups of participants were then followed for one year, at which point the experiment ended. At the end of the year, each of the three groups showed signs of moderate weight loss on average: 15 percent of participants in the “traditional advice” group had lost at least 5 percent of their body weight (the study’s primary outcome measure).
The two groups of 5:2 dieters lost an average of slightly more weight on this scale, with 18 percent of the “self-help” group losing at least 5 percent of their body weight, compared to 28 percent of the “support group” participants. .
But while all groups achieved a moderate weight loss during the trial, there was another key differential factor in the data.
When compared to participants who received traditional advice on weight management, participants on the 5:2 diet rated their experience during the trial a higher score.
In a survey of the trial, dieters in a ratio of 5:2 rated their interventions in terms of benefit from traditional weight management advice, and indicated that they were more likely to recommend the diet to others.
Comments also showed that those following the 5:2 diet were more willing to continue the diet after the trial ended.
In short, you might say that 5:2 dieters generally have a better time trying to stick to their weight loss plan.
“Here we were able to provide the first findings about the effectiveness of simple 5:2 diet advice in a real-world setting,” explains health psychologist Katie Myers-Smith of Queen Mary University of London.
“We found that although the 5:2 diet was no better than traditional approaches in terms of weight loss, users preferred this approach because it was simpler and more attractive.”
According to the researchers, the 5:2 weight loss efficacy seen in the study is roughly the same as that shown in other intermittent fasting studies.
While a 5:2 diet doesn’t seem to produce astonishing results compared to traditional weight management advice, more favorable user reviews could be an important factor to consider for clinicians advising people in the real world who are struggling to lose weight.
In their study, the researchers concluded, “Physicians who provide brief advice on weight management may consider recommending the 5:2 diet.”
“The approach is not superior to standard multimedia advice, but it is simpler and more attractive to users.”
The results are reported in PLUS ONE.