A massive investigation of more than 135,000 people across five continents has revealed that a diet which includes a moderate intake of fruits, vegetables, and fat is linked to longer life. The research also suggests that excessive consumption of carbohydrates can increase the risk of death.
The highest benefits were found in people who incorporated three to four servings of fruits, vegetables and legumes into their diet every day. Victoria Miller is a McMaster University doctoral student and lead author of the paper.
“Our study found the lowest risk of death in those who consumed three to four servings or the equivalent to 375 to 500 grams of fruits, vegetables and legumes per day, with little additional benefit for intake beyond that range,” said Miller. “Additionally, fruit intake was more strongly associated with benefit than vegetables.”
A higher amount of fat, enough to provide 35 percent of energy, was also found to contribute to a lower risk of death compared to lower fat intakes. A diet high in carbohydrates, on the other hand, proved to be dangerous. Eating enough carbohydrates to provide 60 percent of energy or higher was linked to an increase in the risk of death, although not from cardiovascular disease.
The data for the analysis was collected from the Prospective Urban Rural Epidemiology (PURE) study, which followed more than 135,000 people in 18 countries. The study gathered information about the participants’ diets and followed them for an average of seven and half years.
There was no relationship found between dietary fats and major cardiovascular disease, but higher fat consumption was associated with lower mortality. The data included all major types of fats including saturated fats, polyunsaturated fats, and monounsaturated fats. Saturated fats were associated with lower stroke risk.
Co-author Mahshid Dehghan pointed out that the results of the study contradict “the conventional beliefs about dietary fats and clinical outcomes.” She explained that recent dietary guidelines have focused on reducing fat intake in order to reduce the risk of cardiovascular disease without taking into consideration how saturated fat is replaced in the diet.
“A decrease in fat intake automatically led to an increase in carbohydrate consumption and our findings may explain why certain populations such as South Asians, who do not consume much fat but consume a lot of carbohydrates, have higher mortality rates,” said Dehghan.
The research, published as two reports in The Lancet, may help to better inform consumers of their nutritional needs.
“The findings of these studies are robust, globally applicable and provide evidence to inform nutrition policies,” said co-author Andrew Mente. “This is relevant because in some parts of the world nutritional inadequacy is a problem, whereas in other parts of the world nutritional excesses may be the problem.”
The reports will be presented today at the Congress of the European Society of Cardiology in Barcelona, Spain.