A new study has found that low-carbohydrate diets high in plant-based fats and proteins were linked to less long-term weight gain.
ADVERTISEMENTEating plant-based proteins and fats along with whole grains may help to slow long-term weight gain, according to a new study.
Researchers at Harvard University in the US found that this type of low-carbohydrate (or low-carb) diet was better for maintaining weight long-term compared to diets made up of meat and refined starches.
Low-carb diets have already been associated with favourable short-term weight changes, but researchers said that little research has looked at the effect of these diets on our weights long-term.
A diet low in carbohydrates focuses on foods high in protein and fat instead of grains and starchy foods, according to the US-based Mayo Clinic.
“Our study goes beyond the simple question of, ‘To carb or not to carb?’” Binkai Liu, a research assistant in Harvard's nutrition department and lead author of the study, said in a statement.
"It dissects the low-carbohydrate diet and provides a nuanced look at how the composition of these diets can affect health over years, not just weeks or months."
The findings were published last week in the journal JAMA Network Open.
The study included a total of more than 120,000 participants who were part of three studies spanning 1986 to 2018. Participants provided self-reported updates of their diets and weight every four years.
The data analysis was carried out between November 2022 and April 2023.
The researchers looked at five types of low-carb diets including ones that emphasised animal-sourced protein and fat and those that emphasised more plant-sourced proteins and fat.
Their findings suggest that the quality of a low-carb diet "may play a critical role in modulating long-term weight change", the study concluded.
The diets with "high-quality protein, fat, and carbohydrates from whole grains and other plant-based foods were associated with less weight gain," the researchers said.
Their study had limitations, including the fact that the data was self-reported. This means that measurement errors were "inevitable". Confounding factors or biases could also exist as the study was observational.
The study was also limited to mainly white health professionals, which could limit the ability to generalise the findings for a larger population.
Multiple studies have previously linked plant-based diets to lower body mass index (BMI). A study published last year in the European Heart Journal also said plant-based diets may reduce the risk of cardiovascular disease.
“The key takeaway here is that not all low-carbohydrate diets are created equal when it comes to managing weight in the long-term,” Qi Sun, an associate professor at Harvard and senior author of the study, said in a statement.
“Our findings could shake up the way we think about popular low-carbohydrate diets and suggest that public health initiatives should continue to promote dietary patterns that emphasise healthful foods like whole grains, fruits, vegetables, and low-fat dairy products.”
