ARS | Publication request: The 2005 Dietary Guidelines for Americans and Risk of Metabolic Syndrome

Submitted to: American Journal of Clinical Nutrition
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: June 1, 2007
Publication Date: October 1, 2007
Citation: Fogli-Cawley, J., Dwyer, J., Saltzman, E., Mccullough, M., Troy, L.M., Megis, J., Jacques, P. 2007. The 2005 Dietary Guidelines for Americans and Risk of Metabolic Syndrome. American Journal of Clinical Nutrition. 86:1193-1201.

Interpretive Summary: Metabolic syndrome (MetS) has been associated with as much as a three-fold increased risk of cardiovascular disease (CVD). MetS is defined by the National Cholesterol Education Program Adult Treatment Panel III (ATPIII) as abnormal levels of three or more of the following risk factors: abdominal obesity (high waist circumference), hyperglycemia, hypertriacylglycerolemia, low HDL cholesterol, and hypertension. MetS is of particular concern due to its increasing prevalence, which increased from 28% to 32% in US adults from 1988 to 2000. The US Departments of Agriculture and Health and Human Services issue dietary recommendations, the Dietary Guidelines for Americans (DGA), to help reduce the risk of CVD and other chronic diseases. To date, no one has examined the efficacy of the entire set of dietary recommendations included in the sixth version of the DGA, released early in 2005, on markers of CVD risk. We developed the 2005 Dietary Guidelines for Americans Adherence Index (DGAI) to assess adherence to the 2005 DGA dietary recommendations, particularly in relation to chronic disease risk. This study evaluated a diet consistent with the 2005 DGA, as measured by the DGAI, and MetS and its the individual risk factors. DGAI score and metabolic risk factors for MetS were assessed in a cross-sectional study of 3,177 participants from the Framingham Heart Study Offspring Cohort. The DGAI score was inversely related to waist circumference, triacylglycerol, concentration, both diastolic and systolic blood pressure, the prevalence of abdominal adiposity and hyperglycemia. The prevalence of MetS was significantly lower for individuals in the highest DGAI quintile category compared with those in the lowest category when those being treated for any of the risk factors were excluded. There was a significant interaction between DGAI score and age, with the association between the DGAI score and MetS confined largely to adults younger than 55 years. A dietary pattern consistent with the 2005 DGA was associated with a lower prevalence of MetS, a potential risk factor for CVD.

Technical Abstract: The 2005 Dietary Guidelines for Americans Index (DGAI) was created to assess adherence to the dietary recommendations of the 2005 Dietary Guidelines for Americans (DGA) in relation to chronic disease risk. The objective of the present study was to assess the relationship between dietary patterns consistent with the 2005 DGA as measured by the DGAI and both the prevalence of metabolic syndrome (MetS) and individual MetS risk factors. DGAI score and metabolic risk factors for MetS were assessed in a cross-sectional study of 3,177 participants from the Framingham Heart Study Offspring Cohort. MetS was defined using the National Cholesterol Education Program Adult Treatment Panel III (ATPIII) criteria. After adjustment for potential confounders, the DGAI score was inversely related to waist circumference (P-trend <0.001), triacylglycerol concentration (P-trend =0.005), both diastolic (P-trend =0.002) and systolic (P-trend=0.01) blood pressure, the prevalence of abdominal adiposity (P-trend<0.001) and hyperglycemia (P-trend= 0.03). The prevalence of MetS was significantly lower for individuals in the highest DGAI quintile category compared with those in the lowest category (OR 0.64, 95% CI: 0.47-0.88, P-trend=0.005) when those being treated for any of the risk factors were excluded. There was a significant interaction between DGAI score and age, with the association between the DGAI score and MetS confined largely to adults younger than 55 years (OR 0.57, 95% CI: 0.36-0.92, P-trend<0.01). A dietary pattern consistent with the 2005 DGA was associated with a lower prevalence of MetS, a potential risk factor for CVD.