Intermittent fasting has become one of the most popular weight loss regimes in recent years — but now experts say the same benefits could be achieved without restricting calorie intake. Research from the University of Surrey found that cutting back on carbohydrates achieved similar metabolic benefits. Twelve overweight or obese volunteers followed three diets for one day each, with five days of normal eating in between.
These were a normal carb diet, a low-carb diet with balanced calorie intake, and a low-carb diet with significant calorie restriction. Both low-carb diets led to improvements in metabolic markers, a shift towards burning fat for energy, and better handling of a high-fat meal. This included reduced levels of fats called triglycerides which have been linked to heart disease , regardless of calorie restriction.
Study leader Dr Adam Collins, an associate professor of nutrition at the University of Surrey, said: “We found that by simply restricting carbohydrates, without enduring extreme calorie restriction, we can reap the metabolic effects associated with short-term fasting. “This suggests that periodically reducing our carbohydrate intake could be a more accessible and sustainable way for people to manage and improve their metabolic health.” Volunteers experienced increased hunger when eating the low-carb diet.
However, this did not appear to cause an increase in food intake during the following days. The team said this suggested the body may adapt to reduced carb intake, making it easier to follow such a regime long-term. Dr Collins added: “This research offers a promising new perspective on dietary interventions for metabolic health and could have an impact on managing conditions such as type 2 diabetes , heart disease and obesity.
” Intermittent fasting diets typically involve eating normally for five days each week, then dramatically reducing calorie intake for two days. The findings were published in the European Journal of Nutrition..
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A study found this method had the same benefits as intermittent fasting.