Low-fat vegan diet may help people lose weight without eating less

WASHINGTON DC (ANI):

A low-fat vegan diet might support weight loss without the need to count calories, reduce portion sizes, or constantly battle hunger. In a 16-week clinical trial, participants following a diet centred on fruits, vegetables, grains and legumes consumed around 357 fewer calories per day, despite eating nearly the same amount of food overall.

A low-fat vegan diet can reduce the energy density of the foods people eat by about 30 per cent, helping them consume fewer calories while still eating satisfying amounts of food. The approach was also associated with weight loss, even though participants were not instructed to restrict calories, according to new research published in JAMA Network Open.

In a randomised clinical trial involving adults with overweight, participants who followed an ad libitum low-fat vegan diet substantially reduced the number of calories per gram of food they consumed. Researchers found that greater reductions in energy density were tied to lower calorie intake and greater weight loss, despite the absence of any instructions to eat less.

“This helps answer a question people often have about plant-based eating: How can you lose weight without counting calories or going hungry?” said Hana Kahleova, director of clinical research at the Physicians Committee for Responsible Medicine and lead author. “The answer is energy density. Plant foods are rich in water and fibre, so you can fill your plate, feel full, and still take in fewer calories,” according to the Science Daily website.

According to the website, the findings come from an analysis of a 16-week randomised trial involving adults with overweight. Participants were assigned either to an ad libitum low-fat vegan diet centred on fruits, vegetables, grains and legumes, or to a control group that continued eating as usual without making any dietary changes.

Neither group was given a calorie target or told to limit how much they ate. Researchers measured each participant’s dietary energy density by comparing total daily energy intake with the total weight of food consumed, expressed as total energy (kcal/day) divided by total food weight (grams/day).

The study produced several notable findings:

. The total weight of food consumed did not change significantly in either group, meaning those following the vegan diet continued eating about the same amount of food by weight.

. Calorie intake declined in both groups, but the decrease was larger among those following the vegan diet, at about 357 kcal/day.

. Energy density remained essentially unchanged in the control group but fell by about 30 per cent in the vegan group.

. Larger reductions in energy density were associated with greater weight loss, and that relationship remained even after researchers accounted for changes in calorie intake.

FEWER CALORIES

The difference came largely from changes in the types of foods participants were eating. The vegan diet removed calorie-dense animal foods, including meat, dairy and eggs, while increasing consumption of foods that provide more volume for relatively few calories, particularly vegetables and legumes.

Because these plant foods generally contain fewer calories per gram, participants could continue eating generous portions while taking in less energy overall.

“This isn’t about willpower or smaller portions,” Dr Kahleova said. “It’s about choosing foods that naturally deliver fewer calories in every bite. A 30 per cent reduction in energy density is a substantial shift that would be very hard to achieve and sustain through portion control alone.”

The findings suggest that a low-fat vegan diet can substantially reduce dietary energy density, allowing people to consume fewer calories and lose weight without intentionally restricting their calorie intake.