Intermittent fasting has become a popular way to lose weight in recent years, with various eating windows touted as the most sensible and effective. It’s been considered a means to increase heart health and even lower blood pressure, but new information indicates that intermittent fasting and heart health may not be synonymous. Instead, restricting eating to an eight-hour time window can increase the risk of cardiovascular death.

Defining Intermittent Fasting

Time-restricted eating is one type of intermittent fasting; caloric intake is restricted to a window of four to 12 hours out of 24. One popular intermittent fasting option is to eat for eight hours a day and fast for the remaining 16 (8:16), thereby forcing the body to use fat instead of glucose for energy. That 8:16 ratio was studied by the group presenting at the American Heart Association’s Epidemiology and Prevention|Lifestyle and Cardiometabolic Health Scientific Sessions 2024.

Researchers followed more than 20,000 adults who practiced a time-restricted eating plan of eight hours or less per day over a period of eight to 17 years. During that period of time, those in the study had a 91% higher risk of dying from heart disease. Restricting eating to fewer than 10 hours carried a 66% higher risk of dying from stroke or heart disease.

Fasting Isn’t for Everyone

Though there may still be some merit to fasting, the researchers who conducted the study were not expecting to find a 91% increase in the risk for cardiovascular death in relation to intermittent fasting. The team conducting the study emphasized that individuals with a history of or risk factors for heart disease, cancer, Type 1 or Type 2 diabetes, stroke, or any other chronic health condition, should be especially cautious before starting an intermittent fasting program of any sort.

Short-term benefits of fasting may include weight loss and lower blood pressure. However, this first long-term (17-year) study of fasting and its effects on heart health, is the first to find that fasting – intermittent or otherwise – can be dangerous, so it makes sense to look into other options for diet and weight loss.

Proven Heart-Healthy Diet Strategies

With healthy weight loss comes better cardiovascular health, but there are time-tested, heart-healthy diet options that have been proven to increase not only cardiovascular health but overall health. Two to try:

• The DASH Diet: Sanctioned by the National Institutes of Health, the DASH diet, or dietary approaches to stop hypertension, focuses on eating vegetables and fruit, whole grains, and lean protein, and limiting red meat, sugary foods and unhealthy fats. The DASH diet has been proven year over year to be an excellent option for weight loss, weight maintenance and improving overall health.
• The Mediterranean Diet: Lauded by the American Heart Association as well as the National Institutes of Health for lowering weight, cholesterol and improving blood sugar levels, the Mediterranean Diet encourages people to eat foods such as salmon and tuna, olive oil and avocadoes, fresh vegetables, healthy cheeses and yogurt, and even red wine, all in moderation.