The need for accurate nutrition survey methodology: the South Carolina experience

Assessment of two nutrition-related risk factors, obesity and fat intake, was completed on a representative sample of South Carolina adults. Obesity estimates determined from self-reported heights and weights were less than prevalences determined from direct measurements (white males 21.4% vs. 28.2%; white females 20.8% vs. 24.5%; black males 29.2% vs. 30.1%; black females 43.6% vs. 50.6%; and total 24.9 vs. 29.8%). Nine fat-intake habits were identified from dietary mannerisms involving the consumption of red meat, fat on meat, fried fish/chicken, butter, eggs, whole milk, bacon/sausage, and cheese and the use of solid fats when cooking vegetables. The mean number of the nine habits exhibited was four. The total number of habits did not correlate well with serum cholesterol, as 27% of the individuals with none of the nine fat intake habits had blood cholesterol values greater than 6.2 mmol/L (239 mg/100 mL), while only 17% of the individuals with seven habits had the high level of cholesterol. These nine habits explained less than 10% of the variability of serum cholesterol values.