Food Quality More Important Than Low-Fat or Low-Carb Diets

For decades, debates over the best diet for heart health have revolved around reducing fat or carbohydrates. However, new evidence shows that the key to a healthy heart is not merely cutting back on pasta, potatoes, or calories, but the quality of the food consumed.

A major study led by public health researchers from Harvard University reveals that the focus of healthy eating should no longer be on what is removed from the plate, but on what is consumed.

Published in the Journal of the American College of Cardiology, the study monitored nearly 200,000 men and women in the United States over approximately 30 years, accumulating over 5.2 million person-years of follow-up data.

Researchers found that low-fat or low-carbohydrate diets do not automatically lead to better heart health. The key difference lies in food quality: diets rich in processed foods, animal protein, and saturated fats remain high-risk for cardiovascular health, even if they are technically low-carb or low-fat.

Based on the data, participants who consumed a varied diet of high-quality foods—such as vegetables, fruits, whole grains, and healthy fats—showed significantly better health indicators.

Zhiyuan Wu explained that a healthy low-carbohydrate diet and a healthy low-fat diet likely share similar biological pathways for improving cardiovascular health, offering individuals flexibility in choosing a diet that suits their preferences, provided they prioritise food quality.

Dr. Harlan Krumholz, a cardiologist at Yale University and editor-in-chief of the Journal of the American College of Cardiology, stated that the study helps end the long-standing debate between low-carb and low-fat proponents.

“These findings show that the most important factor for heart health is the quality of food consumed. Emphasising plant-based foods, whole grains, and healthy fats is linked to better cardiovascular outcomes,” Krumholz emphasised.

Although the study relies on self-reported data from health-conscious professionals, its three-decade duration provides strong validity. The key message is clear: strict diets counting every carb or gram of fat may not be necessary. Focus on unprocessed whole foods for long-term heart health. (Science Alert/I-2)