In a recent publication in Scientific Reports, researchers investigated the correlation between adherence to the Dietary Approaches to Stop Hypertension (DASH) diet and metabolic health outcomes among overweight and obese adolescents in Iran.
Background:
Adolescent obesity and overweight issues pose significant global health concerns due to their association with metabolic disorders like hypertension, abnormal blood lipid levels, impaired glucose metabolism, and insulin resistance. These conditions escalate the risk of cardiovascular ailments, type 2 diabetes, and premature mortality. Lifestyle factors, notably dietary habits and physical activity levels, significantly influence metabolic health.
Recent studies have suggested a positive correlation between increased consumption of vegetables and fruits and decreased intake of sugary beverages and fats with better metabolic health among overweight or obese individuals. The DASH diet, renowned for its emphasis on vegetables, fruits, whole grains, legumes, seeds, and low-fat dairy products, has garnered attention in adolescent populations. However, conflicting findings necessitate further investigation.
Study Overview:
The cross-sectional study aimed to assess the metabolic effects of adhering to the DASH diet among overweight and obese Iranian adolescents.
Researchers surveyed 203 adolescents aged 12 to 18 years identified as overweight or obese based on body mass index (BMI) calculations using the Quetelet formula. Participants excluded from weight-loss regimens, with no endocrine or genetic disorders, and not using supplements or medications affecting metabolic profiles were considered eligible.
Dietary data were collected through standardized food frequency questionnaires (FFQs), while anthropometric parameters, including insulin levels, blood pressure, lipid profile, and fasting blood sugar, were recorded. DASH scores, derived from eight components reflecting dietary intake, were assessed, emphasizing higher consumption of certain foods (e.g., low-fat dairy, fruits, vegetables) and lower intake of others (e.g., sodium, sweetened beverages, processed meats).
Blood samples were obtained for biochemical analysis, with insulin levels measured via enzyme-linked immunosorbent assays (ELISA). Metabolic health status was determined based on insulin resistance criteria established by the International Diabetes Federation (IDF) and Homeostatic Model Assessment for Insulin Resistance (HOMA-IR).
Physical activity levels and total calorie intake were evaluated using the Physical Activity Questionnaire for Adolescents (PAQ-A) and the United States Department of Agriculture (USDA) food composition database, respectively. Multivariate logistic regression was employed to calculate odds ratios (ORs) for the association between DASH diet adherence and metabolic health, adjusting for relevant variables.
Key Findings:
Participants had a mean age of 14 years and a mean BMI of 27 kg/m². A considerable proportion (39%) exhibited metabolically unhealthy overweight or obesity (MUO) based on IDF criteria, with similar findings (33%) observed when utilizing IDF and HOMA-IR guidelines. Notably, the prevalence of MUO was significantly lower among individuals in the highest DASH tertile compared to the lowest tertile, according to both IDF (10% vs. 67%) and HOMA-IR (10% vs. 61%) criteria.
Those adhering to the DASH diet’s highest tertile demonstrated higher physical activity levels, elevated high-density lipoprotein cholesterol (HDL-c) levels, and lower blood pressure, fasting blood sugar, insulin, triglyceride, and HOMA-IR levels relative to counterparts in the lowest tertile. After adjusting for confounders, individuals in the highest DASH tertile exhibited substantially lower odds of MUO compared to those in the lowest tertile (OR: 0.09).
Additionally, heightened DASH adherence was associated with reduced odds of hyperglycemia, hypertriglyceridemia, insulin resistance, and low HDL cholesterol, with corresponding odds ratios of 0.1, 0.3, 0.1, and 0.3, respectively. Subgroup analysis by BMI and gender revealed a more pronounced association among females (OR: 0.02) compared to males (OR: 0.09). Researchers speculate that the DASH diet’s favorable impact on metabolic health may be attributed to its rich fiber, antioxidants, potassium, magnesium, and low sodium content, contributing to reduced inflammation.
Conclusion:
In summary, the study underscores a significant association between increased adherence to the DASH diet and reduced risks of metabolic diseases among Iranian adolescents, particularly overweight girls. Notably, DASH diet adherence was linked to decreased probabilities of hypertriglyceridemia, hyperglycemia, insulin resistance, and low HDL cholesterol. Future research, including prospective studies, is warranted to corroborate these findings.
The study’s findings suggest that adolescents can improve their dietary quality and alleviate metabolic disease burdens by prioritizing consumption of DASH-associated components like fruits, vegetables, legumes, low-fat dairy, whole grains, seeds, and nuts, while minimizing intake of unhealthy options such as processed meats, red meats, sweetened beverages, and excessive salt.