A Mediterranean diet, rich in vegetable fats such as olive oil or nuts, does not lead to significant weight gain compared to a low-fat diet, finds a new research.
The findings showed that fats from nuts, fish and phenolic-rich vegetable oils found in the Mediterranean diet are healthier than fats from meat and processed foods.
“Our study shows that a Mediterranean diet rich in vegetable fats had little effect on bodyweight or waist circumference compared to people on a low-fat diet,” said lead author Ramon Estruch from the University of Barcelona, Spain.
A Mediterranean diet has been known to reduce mortality, heart diseases as well as cancer.
However, the fear of eating an all fat diet means that a low-fat diet continues to be recommended as a means of weight loss, the researchers said.
“The study certainly does not imply that unrestricted diets with high levels of unhealthy fats such as butter, processed meat, sweetened beverages, deserts or fast foods are beneficial,” Estruch added.
For the study, published in ‘The Lancet Diabetes & Endocrinology’ journal, the team included 7447 participants (men and women) aged 55-80 who were randomly assigned to one of three groups - an unrestricted calorie Mediterranean diet rich in olive oil (2543), an unrestricted calorie Mediterranean diet rich in nuts (2454), or a low-fat diet where the advice was to avoid all dietary fat (2450).
After five years, the low-fat diet group (from 40% to 37.4%) showed a decrease in the total fat intake and both Mediterranean diet groups (40% to 41.8% in olive oil; 40.4% to 42.2% in nuts) showed slight increase.
The percentage of energy intake from protein and carbohydrate decreased in both Mediterranean diet groups.
On average, participants in all three groups lost some weight with the greatest weight loss seen in the Mediterranean diet with olive oil group (0.88 kg weight reduction in the olive oil group, compared to 0.60 kg for the low-fat diet group and 0.40 kg for the nuts group).
“Calorie-obsessed caveats and warnings about healthier, higher-fat choices such as nuts, phenolic-rich vegetable oils, yoghurt should also be dropped. We must abandon the myth that lower-fat, lower-calorie products lead to less weight gain,” commented Dariush Mozaffarian, Professor at Tufts University in the US, in a linked article.