Food Factor

Reducing the amount of saturated fats in the diet can improve heart health, but only if they are replaced with certain foods. Frank B Hu, MD, PhD, study author and professor of nutrition and epidemiology at the Harvard TH Chan School of Public Health, and colleagues analyzed data of nearly 175,000 people enrolled in the Nurses' Health Study and the Health Professionals Follow-up Study. The researchers followed 84,628 women and 42,908 men who were free of diabetes, cardiovascular disease and cancer and documented 7,667 incidents of coronary heart disease. Participants provided information on diet, lifestyle, medical history, and newly diagnosed diseases through questionnaires at baseline and every 2-4 years for 24 to 30 years. Results showed that participants generally replaced calories from saturated fats with calories from low-quality carbohydrates, e.g. white bread or potatoes, but doing this did not reduce their risk of coronary heart disease. However, swapping calories from saturated fats for calories from unsaturated fats (vegetable oils, nuts and seeds) or high-quality carbohydrates, such as whole grains, was associated with a significant reduction in the risk of coronary heart disease. For example, replacing 5% of energy intake from saturated fats with an equivalent intake from either polyunsaturated fats, monounsaturated fats, or carbohydrates from whole grains was associated with a 25%, 15%, and 9% lower risk of coronary heart disease, respectively. “Many physicians could benefit from more in-depth nutritional knowledge to help them counsel their patients on changing their dietary practices in a way that will impact their health,” said Professor Hu. “Our findings suggest that when patients are making lifestyle changes to their diets, cardiologists should encourage the consumption of unsaturated fats like vegetable oils, nuts, and seeds, as well as healthy carbohydrates such as whole grains.”