Women double their risk of developing coronary heart disease if they have high consumption of carbohydrates, according to research published in the Archives of Internal Medicine.
Men’s hearts, however, didn’t seem to be affected by carb consumption. I mention this crucial sex difference because many experts believe that replacing saturated fat with carbohydrates is a major cause of heart disease. If true, it seems to apply only to women.
(Another nutrition science trend to keep an eye on is the thought that excessive consumption of omega-6 fats contributes to hardening of the arteries, including coronary heart disease. I’m talking about soy oil, safflower oil, corn oil, among others. No doubt, we’re eating a lot more omega-6 now than at the start of the 20th century.)
We’ve known for a while that high-glycemic-index eating was linked to heart disease in women but not men. Glycemic index is a measure of how much effect a carbohydrate-containing food has on blood glucose levels. High-glycemic-index foods raise blood sugar higher and for longer duration in the bloodstream.
High-glycemic-index foods include potatoes and white bread, for example.
The study at hand included over 47,000 Italians who were interrogated via questionnaire as to their food intake, then onset of coronary heart disease—the cause of heart attacks—was measured over the next eight years.
Among the 32,500 women, 158 new cases of coronary heart disease were found.
Researchers doing this sort of study typically compare the people eating the least carbs with those eating the most. The highest quartile of carb consumers and glycemic load had twice the rate of heart disease compared to the lowest quartile.
The Cleave-Yudkin theory of the mid-20th century proposed that excessive amounts of refined carbohydrates cause heart disease and certain other chronic systemic diseases. Gary Taubes has also written extensively about this. The research results at hand support that theory in women, but not in men.
Do these research results apply to non-Italian women and men? Probably to some, but not all. More research is needed.
Women with a family history coronary heart disease—or other CHD risk factors—might be well-advised to put a limit on total carbs, high-glycemic-index foods, and glycemic load. I’d stay out of that “highest quartile.” Don’t forget: heart disease is the No. 1 killer of women.
See NutritionData’s Glycemic Index page for information you can apply today.
FYI, the Low-Carb Mediterranean Diet and Ketogenic Mediterranean Diet are also low in glycemic index.
Steve Parker, M.D.
Disclaimer: All matters regarding your health require supervision by a personal physician or other appropriate health professional familiar with your current health status. Always consult your personal physician before making any dietary or exercise changes.
Addendum: Alert reader Nadia Hassan brought to my attention that I had originally written that pasta has a high glycemic index. Citing appropriate references, Nadia convinced me that pasta has a low-to-moderate glycemic index, from around 30 to 60. Its GI also is higher if over-cooked. I corrected my original post.
Sieri, Sabina, et al. Dietary glycemic load and index and risk of coronary heart disease in a large Italian cohort. The EPICOR study. Archives of Internal Medicine, 170 (2010): 640-647.
Barclay, Alan, et al. Glycemic index, glycemic load, and chronic disease risk – a meta-analysis of observational studies [of mostly women]. American Journal of Clinical Nutrition, 87 (2008): 627-637.