If you’re trying to help your heart by cutting out saturated fats, make sure you don’t eat more carbs as a result, say researchers from Aarhus University Hospital in Denmark. Replacing saturated fats with healthier options like fruits, veggies, and whole grains is a much more effective way to help the heart.
A previous study had found that there was no significant heart benefit from cutting fats alone. This prompted the researchers of the study to suggest that people might be replacing them with unhealthy simple carbs, like white bread and potatoes, which might actually negate the effect of cutting out fats.
These results suggest that people who replace saturated fats with high-glycemic foods like refined carbs are actually increasing their risk for heart disease, rather than lowering it.
The new study, lead by Marianne U. Jakobsen, wanted to test this theory, so researchers looked at how the glycemic index of foods plays a role in heart health. Foods with a high glycemic index, like simple carbs (e.g., white bread and white rice), cause a rapid spike in blood sugar, while those with lower glycemic indices lead to a slower rise in blood sugar, and usually include the higher-fiber, complex carbohydrates like whole grains, as well as fruits and veggies.
For the people who were eating high-glycemic diets, their risk of heart attack rose by 33% for every 5% increase in the carbohydrate content of the food they consumed. These results suggest that people who replace saturated fats with high-glycemic foods like refined carbs are actually increasing their risk for heart disease, rather than lowering it.
The team also found that for people in the low-glycemic group, their risk of heart attack dropped 12% for every 5% increase in carbs they consumed. While this finding wasn’t statistically significant, it does suggest that eating more healthy complex (low-glycemic index) carbs may lower heart attack risk. But because the finding could have been due to chance, it’s harder to draw conclusions about the relationship. Eating a diet in the middle range of glycemic index did not have an effect on people’s risk for heart attack.
The researchers conclude that replacing saturated fats with low-glycemic foods – not high-glycemic foods – may be a good way to reduce heart attack risk. Since the glycemic index is not a category on nutrition labels, it’s not always easy to tell where foods fall in it. But looking for foods that are low in sugar and high in fiber is usually good bet for choosing ones that are lower on the glycemic index.
The study was published in the April 7, 2010 issue of the American Journal of Clinical Nutrition.