A review of key dietary patterns and the risk of obesity, type 2 diabetes, and cardiovascular diseases

This review examines how major dietary patterns influence the risk of obesity, type 2 diabetes, and cardiovascular diseases. Eighteen recent studies (between 2021 and 2026) were analyzed using a thematic approach. Evidence consistently shows that whole diet patterns such as the Mediterranean, DASH, Healthy Eating Index, and healthful plant based diets lower cardiometabolic risk by improving lipid profiles, reducing inflammation, and supporting healthy body weight. Studies also show that dietary fat quality matters: diets high in saturated fats increase obesity risk, while those rich in polyunsaturated fats from nuts and seeds are protective. Research on plant based diets highlights that diet quality is essential. Healthful plant based diets reduce BMI, hypertension, and myocardial infarction risk, with especially strong benefits for individuals with high genetic susceptibility. Global studies reveal that Westernized diets are driving rising obesity and chronic disease in regions such as the Eastern Mediterranean, China, Myanmar, and Japan, often replacing protective traditional diets. Public health guidelines, including the Dietary Guidelines for Americans and American Heart Association recommendations, support whole diet approaches but face challenges due to low population adherence, food insecurity, and cultural barriers. Overall, the review concludes that promoting nutrient-dense, culturally adaptable dietary patterns and addressing structural barriers are essential for reducing obesity, type 2 diabetes, and cardiovascular disease.