Study reports low-fat plant-based diet beat low-carb diet in fat loss

A new study from the NIH's National Institute of Diabetes and Digestive Kidney Diseases (NIDDK) reports that when it came to fat loss, participants fed a low-fat plant-based diet experienced better results than participants fed a low-carb animal-based diet. Participants in both groups were allowed to eat as much as they wanted.READ: Study finds plant-based diets cause a surprising boost in metabolism

According to the NIH, the researchers behind this new study set out to evaluate the effects of these two popular — and quite different — diets on the body, including how many calories are consumed on them, their effects of body weight, changes in hormones, and more.

The results were favorable in both categories, but for different reasons. A total of 20 adults spent four weeks consuming one diet for two weeks, followed by the opposite diet for two weeks.

The study notes that the low-carb diet was high in fat and the plant-based diet was high in carbohydrates. Both diets were only minimally processed and included the same quantity of non-starchy vegetables.

As well, the participants — who were allowed to snack and eat as much as they wanted — reported feeling full and satisfied on both diets. However, the participants were found to have consumed a huge 500 to 700 fewer calories daily while on the plant-based diet.

The study found that while both diets resulted in weight loss, it was the low-fat plant-based diet that caused 'significant' fat loss. The results were despite the higher blood sugar and insulin levels in the plant-based diet group, challenging the idea that diets high in carbs will result in increased hunger and eating.

There's good news for people who prefer to eat low-carb diets, however, with the researchers noting that despite the high levels of fat, the participants fed this diet didn't gain weight while benefiting from more steady insulin and blood glucose levels.

As well, the researchers note that the study wasn't intended specifically to look at which diet is best for weight loss, and for that reason, the results may have been different were the participants working with the goal of fat loss. Likewise, the meals were provided in a controlled in-patient setting, meaning everyday real-life dieting may be more difficult to manage.