Diet fads come and go, but researchers have pinpointed one thing that can guarantee weight loss.
Scientists at Johns Hopkins University in the US have ruled out trendy diets such as intermittent fasting as aiding weight loss, labelling it “ineffective”.
Instead, researchers have named sticking to a traditional diet and calorie counting as the best way to lose weight.
The findings are based on 550 adults who were tracked for an average of six years. The average age of the participant was 51, they were mostly women, 80% of the participants were white, and the average BMI was 30.8, which is considered obese.
“Meal timing was not associated with weight change during the follow-up period,” says Professor Wendy Bennett, a senior author of the study, which was published in The Journal of the American Heart Association.
“This includes the interval from first to last meal, from waking up to eating a first meal, from eating the last meal to going to sleep and total sleep duration.”
Intermittent fasting sees dieters only eating between a certain time period every day. For example, if they ate over an eight-hour window, they might fast until midday and eat from 12pm to 8pm.
“The study did not detect an association between meal timing and weight change in a population with a wide range of body weights,” Prof Bennett adds.
Instead, the researchers stress that calorie counting and limiting portion sizes is the key to weight loss – no matter what time of day you eat.
“Eating less overall and fewer large meals may be a more effective weight management strategy than restricting meals to a narrow time window,” Prof Bennett says.
Health records from patients in Maryland and Pennsylvania were analysed, and the team created a smartphone app for patients to log when they sleep, what and when they eat, and when they wake up.
“Frequency and size of meals was a stronger determinant of weight loss or gain than the time between first and last meal,” Prof Bennett continues.
She also debunked the theory that intermittent fasting could improve the body’s metabolism, saying that their study did not detect this link.
The study’s authors have called for further trials including a more diverse population.
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