Record: Laura S. Kibiri, Katy Mitchell, Wayne Brewer, and Alexis Ortiz, “How Healthy is Homeschool? An Analysis of Body Composition and Cardiovascular Disease Risk” in Journal of School Health 88, no. 2 (February 2018): 132-138. [abstract here]
Summary: Kabiri, a professor in Houston Community College’s Physical Therapy Assistant program. Mitchell, Brewer, and Ortiz are all on the faculty at the School of Physical Therapy at Texas Woman’s University. These authors previously published the first study ever of homeschooled children’s gross and fine motor skills, a review of which you can read here.
This time the authors come together again to evaluate the degree to which homeschooling impacts children’s body composition and cardiovascular disease risk. They begin with a literature review establishing that being “overfat” (which they distinguish from being “overweight” to allow for healthy individuals with above average muscle mass) is a risk factor for a number of negative adult outcomes, especially cardiovascular disease. They also provide statistics for the average rates of obesity and so forth among the United States’ children and adolescents.
To compare homeschoolers with these averages, the authors conducted the Fitness Assessment in the Homeschooled (FAITH) study. The study used a sample of 143 children age 5-11 who had been homeschooled for at least one full year. Children attending cyberschools requiring physical education or with significant mental or physical disabilities were excluded. The researchers measured these students’ body mass index (BMI), percent body fat, and waist circumference, and parents filled out a demographic questionnaire. The sample was 85% white, with about 85% of families making over $60,000 a year, and over 80% of primary caregivers (all mothers) having earned a bachelor’s degree or higher. Thus the children sampled here are whiter, richer, and have parents who much better educated than the general population against which they are being compared.
The findings were that homeschoolers in this sample had lower BMI and percent body fat overall than national averages, but that younger homeschooled children had above average waist circumference. By age 8 the waist circumference imbalance had reduced and homeschooled children looked normal.
The authors conclude by recommending that homeschoolers taking advantage of publicly funded resources like online education or extracurricular activities be given health screenings and especially that such screenings include waist circumference measurement given their finding of increased risk there.
Appraisal: This is not the first study of homeschoolers’ body composition. In 2010 Long et al. found, in a study that compared demographically matched pairs of homeschoolers and public schoolers, that homeschoolers got a bit less exercise than do public schoolers but that food intake was about the same. In 2013 Cardel et al. found, in another study that compared matched samples, that homeschooled children consumed on average about 120 fewer calories per day than similar children attending public schools. In both studies differences were not very pronounced. In 2015 Wachob and Alman found that homeschooled girls were a bit below national averages in physical fitness, whereas homeschooled boys were a bit above average, and their small sample also had a higher percentage of overweight or obese teaching parents, which proved causal for the tendency of some of the children in their sample to be overweight or obese as well. Their study, however, did not compare their sample with a control group from their same region, only with national averages.
This new study, like Wachob and Alman, does not account for regional diversity, comparing a local sample to national averages. The authors here recognize the skewed nature of their sample in terms of parent education level and race, but this geographic variable is not mentioned. As rates of childhood obesity vary significantly by state, this is an important consideration. Though it is not mentioned in the study, my guess is that since all four authors are Texas-based that the sample being reported on here was probably from Texas. Texas has childhood obesity rates that are significantly above average, so potentially a finding like that reported here that homeschooled children are have average BMI and percent body fat could actually suggest that Texas homeschoolers are healthier than Texas children who attend public schools. Or, given the high educational status and wealth of the families being sampled, it could actually be that homeschooled children who possess average BMI and percent body fat are in fact less healthy than a public schooled children with a similar demographic profile. All of that is a long-winded way of saying that this study doesn’t tell us very much since it only compares its skewed sample to national averages. Better would have been to follow the procedure of the Long and Cardel articles mentioned above and compare homeschoolers to a demographically similar sample of public schoolers from the same region.
Milton Gaither, Messiah College