Short-term weight loss in overweight/obese low-income women improves plasma zinc and metabolic syndrome risk factors.

Metabolic syndrome is a group of disorders involving obesity, insulin resistance, dyslipidemia and hypertension. Obesity is the most crucial risk factor of metabolic syndrome, because it is known to precede other risk factors. Obesity is also associated with disturbances in the metabolism of the trace mineral, zinc. The overall purpose of this study was to investigate the effects of short-term weight loss on plasma zinc and metabolic syndrome risk factors. An 8-week weight loss intervention study was conducted with 90 low-income overweight/obese mothers, whose youngest child was 1-3 years old. Plasma levels of zinc, glucose, insulin, leptin, triglycerides, total, high-density lipoprotein (HDL) and low-density lipoprotein (LDL) cholesterol were measured and compared at weeks 0 and 8 of the weight loss program. At pre-study, plasma zinc was low in 39% and, within normal values in 46%, of obese/overweight mothers. By the end of intervention, plasma zinc rose by 22% and only 5% of the mothers continued to exhibit low plasma zinc. At post-study, the metabolic syndrome risk factors of waist circumference, HDL cholesterol, and diastolic blood pressure (p<0.05) showed significant improvements. Plasma zinc increased by a greater margin (67%) in women with low zinc, as compared to those with normal zinc (18%); weight reduction was similar in both the groups. Finally, changes in % body fat were related negatively with changes in plasma zinc (r=- 0.28, p<0.05). The circulating levels of zinc, as well as the metabolic syndrome components, showed significant improvements in overweight/obese low-income women after weight loss.

Relative validity and reliability of a food frequency questionnaire for a triethnic population of 1-year-old to 3-year-old children from low-income families.

OBJECTIVE: To develop and validate a food frequency questionnaire (FFQ) for low-income, 1- to 3-year-old Hispanic, African-American, and white children. DESIGN: A convenience sample of low-income mothers provided dietary data for their child via FFQs and 3-day diet records. SUBJECTS/SETTING: Participants (N=77) were recruited from Special Supplemental Program for Women, Infants, and Children clinics and public health clinics. All subjects were Hispanic, African-American, or white mothers of children 1 to 3 years old, 18 years of age or older, income less than 200% of the federal poverty level, and were literate in English. Statistical analyses performed Wilcoxon signed-ranks tests were used for comparisons of food group servings on time 1 and time 2 FFQs and to examine differences in food group servings between the FFQ and diet records. Spearman correlations were calculated to assess test-retest reliability and the relative validity. Contingency tables were used to determine the degree of association between the FFQ and diet records. RESULTS: Reliability correlations were significant for all nine food categories ( =0.69), ranging from 0.53 (soups) to 0.84 (nonstarchy vegetables). Validity correlations were significant for all food groups ( =0.41) except starchy vegetables. Thirty-six percent of children were classified into the same quartile of food group intake and 78% into the same or within one quartile. CONCLUSIONS: The FFQ yielded excellent reliability and acceptable validity and can be used to assess food choices in a triethnic sample of low-income 1- to 3-year-old children.