Christopher M. Vukadinovich

The effects of an educational intervention on calcium intake and bone mineral content in young women with low calcium intake.

Purpose. This study evaluated whether a combined behavioral and dietary intervention would affect young womens calcium intake and bone mineral content (BMC). Design. The design was a two by three mixed design with one between-subjects factor (treatment vs. control) and one within-subjects factor (time—baseline, 3-month, and 6-month). Setting. The study was conducted in a university setting in Memphis, Tennessee. Participants. A total of 80 premenopausal women (ages 18 to 30) with low baseline calcium intake (< 700 mg/d) were included in the analyses. There were 40 women in the treatment group and 40 women in the control group. Measures. Hertzler and Frarys rapid assessment questionnaire was employed to evaluate calcium intake, and dual-energy x-ray absorptiometry (DEXA) was employed to assess BMC. Results. Repeated measures analysis of variance (RM ANOVA) was employed to analyze results. Results indicated that women in the treatment group made greater increases in total calcium intake and supplemental calcium than women in the control group and that all women made significant increases in dietary calcium intake. Additionally, analyses of BMC revealed that women in the treatment group did not experience significant changes in total BMC, and women in the control group experienced significant losses in total BMC. Conclusions. In the current study, women were losing BMC, and the women who made the largest increases in calcium intake were able to retard this bone loss. There is increasing evidence that dietary calcium intake in young people is extremely low, and the results of the current study highlight the need for much more intensive evaluations investigating the factors that are positively associated with premenopausal bone mineral change.

Comparison of nutritional intake in US adolescent swimmers and non-athletes

Swimming is a very popular sport among adolescents in the US. Little is known about the diet of competitive adolescent swimmers in the US but data from other countries indicate several inadequacies, including excessive intake of fat and lower than recommended intake of carbohydrate and several micronutrients that may affect athletic performance and bone accrual. We assessed usual diet, using a food frequency questionnaire and calcium checklist, among 191 adolescent males and females [91 swimmers (mean 13.7, s = 2.5 years) and 100 non-athletes (mean 14.4, s = 2.8 years)]. For both males and females, swimmers and non-athletes generally had similar average intakes of macro- and micro-nutrients, including higher than recommended amounts of total fat (36%) and saturated fat (12%), and inadequate amounts of calcium, vitamin D, and daily servings of fruits, vegetables, grains, and dairy products. This first study of nutritional intake among adolescent swimmers in the US suggests that dietary habits of adolescents who swim competitively may jeopardize optimal athletic performance and place them at risk for future chronic diseases, including osteoporosis.