High glycaemic index diets could put women, but not men, at greater risk of CHD, research suggests.
Italian researchers studied the diets of 47,749 men and women to determine the effect of dietary carbohydrate on CHD risk.
Until now, only a small number of inconclusive studies have been performed in this area. However, some studies had suggested a link between high glycaemic load (GL) and CVD.
High carbohydrate intake increases levels of triglyceride and reduces HDL cholesterol in the blood, while raising glucose and insulin levels.
All of these fit a profile expected to increase the risk of CHD, the authors noted.
Carbohydrate foods are rated using the glycaemic index (GI), which measures by how much a food raises blood glucose levels. GL is a product of the GI and total carbohydrate content of a food.
In this study, researchers assessed volunteers' diets using food questionnaires to calculate dietary GL over eight years.
During this time 463 people developed CHD.
The researchers found women who consumed the most carbohydrates had 2.2 times the risk of developing CHD, compared with those who ate the least.
However, the research did not show the same link in men. The researchers suggested this may be because the effects of carbohydrates are stronger risk factors of CHD in women than men. Carbohydrates classed as high-GI foods were associated with a greater risk of CHD, but low-index foods were not.
The authors said: 'Thus, a high consumption of carbohydrates from high-GI foods, rather than the overall quantity of carbohydrates consumed, appears to influence the risk of developing CHD.'
They concluded: 'We tentatively suggest that the adverse effects of a high glycaemic diet in women are mediated by sex-related differences in lipoprotein and glucose metabolism, but further prospective studies are required to verify a lack of association of a high dietary GL with cardiovascular disease in men.'