Advertisement

Low-carb diets 'no better' than traditional focus on fat

University of Stanford researchers analysed 609 dieters - PA
University of Stanford researchers analysed 609 dieters - PA

Increasingly trendy low-carbohydrate diets are no more effective than traditional low-fat diets, scientists have said.

A new study involving more than 600 overweight adults found both worked similarly well if adhered to strictly for a year.

Dieting strategies which focus on carbohydrates have come into vogue in recent years and have won the backing of celebrities from Jennifer Aniston to Mick Jagger.

But last night experts said the research showed the key to losing weight was simply eating less.

The study by the University of Stanford, California, found that after 21 months participants on both the low-carbohydrate and low-fat diets had each lost an average of 13lbs (5.9 kilos).

But the results revealed massive variations, with participants losing up to 60lbs (27.2 kilos) in a year while others actually gained weight.

Study lead author Professor Christopher Gardner said the findings may dismay "those who have chosen sides in the low fat versus low-carb diet debate".

He said the study showed the fundamental strategy for getting in shape with either a low fat, or carbohydrate, approach should be similar.

Namely, eating less sugar and refined flour and as many vegetables as possible, while prioritising whole foods - those which have been processed or refined as little as possible.

healthy diet
healthy diet

"On both sides, we heard from people who had lost the most weight that we had helped them change their relationship to food, and that now they were more thoughtful about how they ate,” said Professor Garner.

The researchers also found no link between a person's individual genetic make up - or their insulin secretion level - and how much weight they lost.

Previous research has suggested variations in these could make it easier for some to slim down, depending on the kind of diet they adopt.

Published in the Journal of the American Medical Association (JAMA), the stuy analysed 609 men and women aged 18 to 50 were randomly split into two dietary groups - low carbohydrate or low fat - and followed from April 2015 until May 2016.

Prof Gardner said this allowed the "strongest inferences" to be made from each intervention, with neither option superior.

He said: "We have all heard stories of a friend who went on one diet - it worked great - and then another friend tried the same diet, and it didn't work at all.

"It is because we are all very different, and we are just starting to understand the reasons for this diversity. Maybe we should not be asking what is the best diet, but what is the best diet for whom?"

Past research has shown that a range of factors, including genetics, insulin levels which helps regulate glucose in the body and gut bacteria, or the microbiome, might tip the scales when it comes to weight loss.

But Prof Gardner and colleagues showed neither genetics nor insulin encouraged an individual's body to favour a low-carbohydrate or low-fat diet.

This was after sequencing part of the participants genome before the study began.

Tam Fry, from the National Obesity forum, a UK campaign group, said: " It is refreshing to see Dr Gardner's honesty after his year of toil.

“The best diet in town is not a fad but much less of what you actually fancy - and stick to it. "