Current Research - The Relationship of Dietary and Lifestyle Factors to Bone Mineral Indexes In Children

Objective To identify factors related to children\u27s bone mineral indexes at age 8 years, and to assess bone mineral indexes in the same children at ages 6 and 8 years. Design Bone mineral content (BMC [g]) and bone mineral density (BMD; calculated as g/cm(2)) were measured by dual-energy x-ray absorptiometry (DEXA) in children and their mothers when the children were 8 years of age. A subset of children had an earlier DEXA assessment at age 6 years. Children\u27s dietary intake, height, weight, and level of sedentary activity were assessed as part of a longitudinal study from ages 2 months to 8 years. Subjects/setting Fifty-two healthy white children (25 male, 27 female) and their mothers. Main outcome measures Children\u27s total BMC and BMD at age 8 years. Statistical analyses performed Correlations and stepwise multiple regression analyses. Results Factors positively related to children\u27s BMC at age 8 years included longitudinal intakes (ages 2 to 8 years) of protein, phosphorus, vitamin K, magnesium, zinc, energy, and iron; height; weight; and age (P≤.05). Factors positively related to children\u27s BMD at age 8 years included longitudinal intakes of protein and magnesium (P≤.05). Female sex was negatively associated with BMC and BMD at age 8 years (P≤.05). Children\u27s bone mineral indexes at ages 6 and 8 years were strongly correlated (r=0.86, P<.0001 for BMC; r=0.92, P<.0001 for BMD). Conclusions Because many nutrients are related to bone health, children should consume a varied and nutrient-dense diet

Longitudinal Calcium Intake is Negatively Related to Children\u27s Body Fat Indexes

Objective To determine if dietary calcium was negatively related to children\u27s body fat (BF), if BF indexes and calcium intakes changed over time, and to identify variables related to BF and calcium intake. Design Percent BF and kg BF were assessed by dual energy x-ray absorptiometry (DEXA) in 8-year-old children. In a prospective design, height, weight, dietary intakes, and related variables were monitored longitudinally. from ages 2 months to 8 years during in-home interviews. Subjects Fifty-two white children, (n=25 boys, 27 girls) participated in a longitudinal study with their mothers. At 8 years of age, mean BMI was 17.3 +/- 2.1 (standard deviation) for boys and 17.1 +/- 2.5 for girls. Analyses Regression analysis of all variables, followed by further regression analysis on selected models. Results At 8 years, percent BF was 22.7 +/- 6.7 for boys and 26.2 +/- 7.9 for girls, as assessed by DEXA. Dietary calcium (mg) and polyunsaturated fat intake (g) were negatively related to percent BF (P=.02 to.04) in 3 statistical models, which predicted 28% to34% of the variability in BF among children. Variables positively associated with percent BF were total dietary fat (g) or saturated fat (g), female gender, sedentary activity (hours/day), father\u27s BMI, and mothers\u27 percent BF. Calcium intakes were significantly correlated over time. Dietary variety was positively related to calcium intake, and intakes of carbonated beverages and other sweetened beverages were negatively related. Applications/conclusions Children should be strongly encouraged to regularly include calcium-rich foods and beverages in their diets

Longitudinal Study of Nutrient and Food Intakes of White Preschool Children Aged 24 to 60 Months

Objective: To determine nutrient and food intakes of 72 white preschool children primarily from families of middle and upper socioeconomic status and to compare children\u27s nutrient intakes with current recommendations. Design: Six in-home interviews were conducted with mothers when children were 24 to 60 months old; at each time mothers provided 3 days of dietary information on the child. Children and mothers independently provided information on the child\u27s favorite and least favorite foods at 42 and 54 months. Subjects: Preschool children (24 to 60 months old) participating in a longitudinal study. Statistical analyses: Mean nutrient intakes were compared with the most recent Recommended Dietary Allowances/Adequate Intakes. Differences over time were tested with repeated-measures analysis of variance; gender differences were determined with t tests. Food frequencies (ie, percentage of children consuming specific foods) were determined from dietary recalls and food records. Dietary variety was assessed with the Variety Index for Toddlers or the Variety Index for Children. Results: Means were consistently less than the RDA/AI for energy, zinc, folate, and vitamins D and E. Energy, carbohydrate, and fat intakes were highest (P≤.01) at 60 months. Boys consumed more (P≤.05) protein (10 g), calcium (197 mg), magnesium (35 mg), and pantothenic acid (0.8 mg) at 60 months than did girls. Foods most commonly eaten were fruit drink, carbonated beverages, 2% milk, and french fries. The vegetable group consistently had the lowest variety scores; vegetables also dominated least favorite foods lists. Applications: Parents need to be encouraged to include more sources of zinc, folate, vitamin E, and vitamin D in children\u27s diets. Parents should also encourage their children to eat more vegetables, zinc- and folate-fortified cereals, lean red meats, seafood, vegetable oils, and low-fat milk