Scientists from Tufts University have found that eating at least three servings of whole grains each day may help slow increases in waist size, blood pressure, and blood sugar—key factors linked to heart disease.
Heart disease risk can rise due to lifestyle, age, family history, and certain medical conditions. In the United States, nearly half of adults (47%) have at least one major risk factor: high blood pressure, high cholesterol, or smoking.
Whole grains include all parts of the grain—the bran, germ, and endosperm.
Unlike refined grains, they retain their fibre and micronutrients, which may offer protective health effects.
While previous studies have suggested that whole grains reduce the risk of heart disease, fewer studies have closely examined how whole-grain and refined-grain intake affects specific risk factors over time.
In this study, researchers analyzed data from more than 3,000 participants in the long-running Framingham Offspring cohort. Over an 18-year period, they assessed how whole-grain and refined-grain consumption related to changes in waist circumference, HDL (“good”) cholesterol, triglycerides, blood sugar, and blood pressure.
The findings showed that people who consumed more whole grains had smaller increases in waist size, fasting blood sugar, and systolic blood pressure.
The benefits appeared especially strong for women when it came to controlling waist circumference. Higher whole-grain intake was also linked to increases in HDL cholesterol and declines in triglyceride levels, both of which can support better heart health.
In contrast, eating more refined grains was associated with larger increases in waist size and smaller reductions in triglycerides, suggesting less favorable long-term effects.
Based on the results, the researchers conclude that for middle-aged and older adults, replacing refined grains with whole grains may help reduce body fat, improve cholesterol patterns, and stabilize blood sugar levels over time—factors that together may lower the risk of heart disease.
Dyslipidemia—an imbalance of lipids such as cholesterol and triglycerides—can develop due to diet, tobacco exposure, or genetics, and is a major contributor to heart disease. Improving diet quality, including choosing whole grains, may help reduce this risk.
The study was published in the Journal of Nutrition and conducted by Nicola McKeown and colleagues.
