by Tony Neal, Graduate Nutrition Student
Sugar! Everyone loves it but is it good or bad for you? Today’s society has been placing a negative spin on sugar (carbohydrates). All of the new diets that have emerged have emphasized reducing the amount of carbohydrates a person consumes to promote weight loss. For example, the Atkins diet and the keto diet contain low carbohydrate intake as the main component. Are those diets better than a typical United States diet? Some might say yes. There have been studies that have shown a correlation between cancer and carbohydrate intake. Although cancer is a significant disease that affects many populations, cardiovascular health is an area of interest that deserves some attention.
Cardiovascular disease is any disease that affects the normal functions of the heart and blood vessels. According to the Centers for Disease Control and Prevention (CDC), heart disease and diabetes are among the top causes of death among United States citizens. Since heart disease and diabetes are two things that cause death among Americans; how to lower the risk factors for those diseases should be studied. An important study tested the effects of carbohydrates on cardiovascular disease risk factors and insulin sensitivity, which yielded some helpful information about what types of carbohydrates should be consumed to help with heart health and diabetes.
In the study, the researchers wanted to test if different carbohydrates types will have a greater effect on cardiovascular risk factors and insulin sensitivity. The researchers tested different combinations of carbohydrate diets: a high carbohydrate diet with low glycemic index foods, a high carbohydrate diet with high glycemic foods, a low carbohydrate diet with low glycemic index foods, and a low carbohydrate diet with high glycemic index foods. High glycemic foods are foods that cause a quick spike in blood glucose and insulin levels, which has been associated with diabetes and cardiovascular disease. Low glycemic index foods take longer to increase blood glucose and insulin levels.
Low glycemic index foods have been associated with weight loss. In the study, 163 subjects that completed the program. The study excluded individuals that were either unwilling to eat the provided diets, had certain preexisting medical conditions (diabetes or cardiovascular disease), and/or had a body mass index greater than or equal to 25 kg/m2. The researchers also tailored the experiment to women and black individuals. They chose to increase the population of black individuals tested due to their increased chance of having diabetes and cardiovascular disease.
Each of the subjects was given a Dietary Approaches to Stop Hypertension (DASH) diet and placed in either a high carbohydrate or low carbohydrate group. In the groups, the subjects were then further divided into high glycemic or low glycemic subgroups. The study was carried out over five weeks with a two-week break where the subjects ate a diet that they selected.
The study revealed some interesting facts. The low carbohydrate, low glycemic index group had a lower blood triglyceride level than the low carbohydrate, high glycemic index group. Also, there was an increase in LDL cholesterol and decreased insulin sensitivity in the low glycemic, high carbohydrate group compared to the high glycemic, high carbohydrate group. The results of the study were unexpected. It is believed that low glycemic index foods decrease inflammation and decrease cardiovascular disease risks.
However, the study results prove that there must be other factors involved in cardiovascular health and insulin sensitivity and their relationship with carbohydrates. Also, the study results show that when following a healthy diet, like the DASH, the glycemic index has no significant effect on the risk factors associated with cardiovascular disease and diabetes.
Some types of sugars can be harmful, but with moderation and increased activity levels, cardiovascular disease risk factors will decrease and promote a healthier lifestyle for Americans.