Relative Weight Status Research Articles

Changes in BMI: An Important Metric for Obesity Prevention: In Reply

We thank Chiolero et al for their thoughtful response regarding BMI z score as an important metric for obesity prevention. We agree that BMI z score is an important metric for clinical trials in obesity but less so for prevention trials. In our study, we reported both BMI z score and relative weight-status category (ie, overweight, obese, etc). We focused on weight categories for at least …

Activity, Inactivity, and Screen Time in Relation to Weight and Fatness Over Adolescence in Girls

The impact of activity and inactivity on relative weight and fatness change are best evaluated longitudinally. We examined the longitudinal relationship of physical activity, inactivity, and screen time with relative weight status and percentage body fat (%BF) and explored how it differed by parental overweight status. Non-obese pre-menarcheal girls (173), 8 to 12 years old, were followed until 4 years post-menarche. %BF, BMI z-score, and time spent sleeping, sitting, standing, walking, and in vigorous activity were assessed annually. We developed a physical activity index to reflect time and intensity of activity. Inactivity was defined as the sum of time spent sleeping, sitting, and standing. Screen time was defined as time spent viewing television, videotapes, or playing video games. Parental overweight was defined as at least one parent with BMI>25. In separate linear mixed effects models, activity, inactivity, and screen time were unrelated to BMI z-score longitudinally, with and without accounting for parental overweight. After controlling for parental overweight, activity was inversely related (p<0.001), and inactivity was directly related (p<0.035) to increased %BF longitudinally. Screen time was unrelated to %BF change. With stratification for parental overweight, effects of activity and inactivity on %BF were observed only among girls with at least one overweight parent. In this cohort of initially non-overweight girls, activity and inactivity were related to accrual of BF over adolescence, particularly among children with at least one overweight parent. These results suggest that girls with a family history of overweight represent a target population of high priority for interventions around physical activity and inactivity.

Energy‐Dense Snack Food Intake in Adolescence: Longitudinal Relationship to Weight and Fatness

The longitudinal relationship between the consumption of energy-dense snack (EDS) foods and relative weight change during adolescence is uncertain. Using data from the Massachusetts Institute of Technology Growth and Development Study, the current analysis was undertaken to examine the longitudinal relationship of EDS food intake with relative weight status and percentage body fat and to examine how EDS food consumption is related to television viewing. One hundred ninety-six nonobese premenarcheal girls 8 to 12 years old were enrolled between 1990 and 1993 and followed until 4 years after menarche. At each annual follow-up visit, data were collected on percentage body fat (%BF), BMI z score, and dietary intake. Categories of EDS foods considered were baked goods, ice cream, chips, sugar-sweetened soda, and candy. At study entry, girls had a mean +/- SD BMI z score of -0.27 +/- 0.89, consumed 2.3 +/- 1.7 servings of EDS foods per day, and consumed 15.7 +/- 8.1% of daily calories from EDS foods. Linear mixed effects modeling indicated no relationship between BMI z score or %BF and total EDS food consumption. Soda was the only EDS food that was significantly related to BMI z score over the 10-year study period, but it was not related to %BF. In addition, a significant, positive relationship was observed between EDS food consumption and television viewing. In this cohort of initially nonobese girls, overall EDS food consumption does not seem to influence weight status or fatness change over the adolescent period.

Dairy food consumption and body weight and fatness studied longitudinally over the adolescent period.

Although research suggests that adolescents, particularly girls, may avoid dairy products due to concerns that these foods are 'fattening,' the longitudinal relation between consumption of dairy foods and relative weight status during adolescence has not been explored. Using data from the MIT Growth and Development Study, a longitudinal study designed to assess the metabolic, dietary, and behavioral factors that predict changes in body composition with growth and development in girls during the adolescent period, the current analysis was undertaken to examine the relation of dairy food intake with relative weight status and percentage body fat (%BF). A total of 196 nonobese premenarcheal girls 8-12 y old were enrolled between 1990 and 1993. Girls were followed until 4 y postmenarche. At each annual follow-up visit, data were collected on %BF by BIA, body mass index (BMI) z-score, and dietary intake (assessed by FFQ). The present analysis is limited to the 178 girls who have at least three annual visits and who have valid anthropometric and food frequency data. In all, 1198 individual measurements were analyzed. At study entry, participants had a mean (s.d.) BMI z-score of -0.27 (0.89), a mean (s.d.) %BF of 23.4 (4.7), and obtained 19.9% (9.2) of daily calories from dairy foods. Linear mixed effects modeling indicated no relationship between BMI z-score or %BF and measures of dairy food or calcium consumption. Avoidance of dairy foods due to a possible association with relative body weight is not supported by these findings. We find no evidence that dairy food consumption is associated with BMI z-score or %BF during adolescence, but further research specifically designed to address this question is needed.

From the Feds

From the Feds

Use of self-report to monitor overweight and obesity in populations: some issues for consideration

ObjectiveTo examine the validity of self-reported height and weight data reported over the telephone in the 1997 NSW Health Survey, and to determine its accuracy to monitor overweight and obesity in population surveys. MethodSelf-reported and measured heights and weights were collected from 227 people living in Western Sydney, who had participated in the NSW Health Survey 1997. ResultsSelf-reported (SR) weights and heights led to misclassification of relative weight status. BMI, based on measured weights and heights, classified 62% of males and 47% of females as overweight or obese, compared with 39% and 32%, respectively, from self-report. ConclusionsCaution should be used when interpreting SR height and weight data from surveys, because BMI derived from these is likely to underestimate the true prevalence of overweight and obesity. ImplicationsSR data have a place in nutrition monitoring because they are relatively inexpensive and easy to collect. However, classifying people into weight categories on the basis of accepted cut-points, using SR heights and weights, yields inaccurate prevalence estimates. Periodic sub-studies of the validity of SR heights and weights are needed to indicate the extent to which the validity of SR is changing.

High-Energy, High-Protein, Oral, Liquid, Nutrition Supplementation in Patients with HIV Infection: Effect on Weight Status in Relation to Incidence of Secondary Infection

Objective To evaluate the use of high-energy, high-protein, oral, liquid, nutrition supplementation and nutrition counseling on the weight status of patients infected with the human immunodeficiency virus (HIV) with and without secondary infections. Design Prospective, descriptive, intervention trial. Follow-up clinic visits were scheduled every 1 to 3 weeks for at least 6 weeks to monitor weight, gastrointestinal symptoms, number of supplements consumed, and incidence of secondary infections. Subjects/setting Community-based, HIV-infected patients, with and without an acquired immunodeficiency syndrome (AIDS) defining illness, who were receiving outpatient medical care at Deaconess Hospital. Twenty-two patients enrolled; however, 4 dropped out and 1 died, so 17 were eligible for evaluation. Intervention Dietary counseling consisted of recommendations to consume a high-protein diet (1.5 g/kg ideal body weight); select foods that minimize gastrointestinal complications; and take at least one high-energy, high-protein, oral, liquid, nutrition supplement daily. Main outcome measures Energy intake from the supplements and weight change over time in relation to whether a secondary infection occurred. Statistical analysis Means, standard deviations, and frequency. Results At the time of entry to the study, the patients with preexisting weight loss (16 of 17) were 14+8% below their usual body weight. On average, patients consumed 11±4 supplements per week for 6±3 weeks. The majority (12 of 17) were able to gain or maintain weight. Overall weight change was 1.1+2.2 kg. Only 5 of 17 patients lost weight, 4 of whom developed a secondary infection during the study (ie, after enrollment in the study). All of those who developed a secondary infection were classified as having AIDS and had lower mean CD4 counts at baseline than those who did not develop a secondary infection. Although those who developed a secondary infection had a higher incidence of weight loss, their consumption of oral supplements per week was greater than that of those without a secondary infection. Applications/conclusions In patients with HIV infection and in the early stages of AIDS without a secondary infection, weight gain and/or maintenance was achievable with a high-energy, high-protein, oral, liquid, nutrition supplement in conjunction with nutrition counseling. The majority of the patients who developed a secondary infection, however, lost weight despite the use of supplements and counseling. Use of a high-energy, high-protein, oral, liquid, nutrition supplement, with intact nutrients, should be the first-line nutrition treatment for malnourished, HIV-infected patients without secondary infections. J Am Diet Assoc. 1996; 96:337-341.

Inaccuracy of self-reported weights and heights among American Indian adolescents

To determine the accuracy of self-reported weights and heights and of relative weight status in a sample of American Indian adolescents, a survey was conducted in middle and high schools on or near three Indian reservations—Navajo, Choctaw, and Blackfeet. Self-reported weights and heights were compared with measured weights and heights. Participants were 12 through 19 years old (N = 806, 47.4% male). Overall, both boys and girls underreported weight (mean difference = self-reported − measured mean values) (−3.4 ± 13.1 and −4.6 ± 13.0 lb, respectively) and overreported height (0.6 ± 2.1 and 0.2 ± 2.6 in, respectively). However, underweight boys and girls overreported weight (4.1 ± 13.8 and 1.6 ± 6.4 lb, respectively) while normal-weight and overweight respondents underreported weight (normal: −1.6 ± 7.9 and −1.4 ± 6.3; overweight: −7.5 ± 17.9 and −11.6 ± 19.0 lb, respectively). Although correlations between measured and reported weight, height, and body mass index (BMI) were high, the sensitivity of relative weight categories based on BMI using self-reported weight and height compared with measured weight and height was poor: 66.7% for underweight (BMI < 15th percentile, based on a national reference population), 88.9% for normal weight, and 73.6% for overweight (>85th percentile). These results call into question the accuracy of self-reported weight and height measurements among American Indian youth and are similar to findings among non-American Indian adolescents. Therefore, their use in prevalence studies should be avoided, and they should be used cautiously in other types of epidemiologic studies.

Alcohol consumption, cardiovascular risk factors, and mortality in two Chicago epidemiologic studies.

Multivariate analysis of the association at baseline between problem drinking and cardiovascular risk factors among 1,233 white male employees of the Chicago Peoples Gas Company age 40-59 showed the 38 problem drinkers with significantly higher blood pressures and cigarette consumption and significantly lower relative weights than the others. Similar analysis among 1,899 white male employees of the Hawthorne Works of the Western Electric Company in Chicago age 40-55 showed the 117 men consuming 5 or more drinks per day with significantly higher blood pressures and cigarette use than the others. No significant differences were recorded between heavy drinkers and the others in serum cholesterol level. The gas company problem drinkers had significantly higher 15-year mortality rates from all causes, cardiovascular diseases, coronary heart disease, and sudden death. These differences could not be entirely explained by their blood pressure, smoking, and relative weight status. The Western Electric heavy drinkers had increased 10-year mortality rates both for all causes and noncardiovascular causes.