Diets that replace carbohydrates with protein or fat should be avoided due to a possible association with shortened life spans, scientists warn.
The study, published in the Lancet Public Health journal, says low-carb diets are popular in Europe and the US, where the research was carried out.
The findings also suggest that while replacing carbohydrates with animal-based proteins and fats from foods such as beef, lamb, pork, chicken and cheese was associated with a greater risk of mortality, eating more plant-based proteins and fats from foods such as vegetables, legumes and nuts was linked to lower mortality.
The observational study of more than 15,400 people in the US found diets low and high in carbohydrates were linked with an increase in mortality, while moderate consumers had the lowest risk of mortality.
The primary findings were confirmed in a meta-analysis of studies on carbohydrate intake including more than 432,000 people from over 20 countries.
Dr Sara Seidelmann, clinical and research fellow in cardiovascular medicine from Brigham and Women's Hospital, Boston, who led the research, said: "Our data suggests that animal-based low carbohydrate diets, which are prevalent in North America and Europe, might be associated with shorter overall life span and should be discouraged.
"Instead, if one chooses to follow a low-carbohydrate diet, then exchanging carbohydrates for more plant-based fats and proteins might actually promote healthy ageing in the long term."
Previous trials have shown low-carbohydrate diets are beneficial for short-term weight loss but there have been conflicting results from research on the long-term impact of carbohydrate restriction on mortality.
