A handful of nuts a day could prevent people from putting on weight in later life, US researchers have said.
A team from Harvard University and Harvard Medical School looked at health data from thousands of people to determine whether changing a person’s nut consumption affected long-term weight gain.
Participants were healthcare professionals and were aged between 24 to 75 years old. At the beginning of the study all the participants were free of chronic disease. Every four years they were asked to answer questions about their weight and their food intake, which included nut consumption.
Average weight gain of the participants was 0.32kg (0.7lbs) each year. The results showed that in each 4-year interval, those regularly consuming half a serving of nuts per day were gaining less weight.
Indeed, those regularly consuming half a serving per day of walnuts or other tree nuts were gaining around 0.4kg less body weight.
With less weight being gained by those eating nuts, the risk of developing obesity was also lower. There was a 3% lower risk of obesity for those having half a serving of any nuts per day, a 15% lower risk for having half a serving per day of walnuts, and an 11% lower risk for those having half a serving per day of other tree nuts.
Lead study author Dr Xiaoran Liu, a research associate in the Department of Nutrition at the Harvard T.H. Chan School of Public Health in Bosto, said: “Our results indicate that increased consumption of total nuts or any types of nut (including peanuts) is associated with less long-term weight gain, despite being calorically dense.
“Incorporating nuts as part of a healthy dietary pattern by replacing less healthful foods may help mitigate the gradual weight gain common during adulthood and beneficially contribute to the prevention of obesity.”
Nuts are rich in nutrients such as vitamins, minerals, protein, fat, fibre and relatively low in carbohydrate.
The study findings have been published in the BMJ Nutrition, Prevention & Health journal.