Relationship between selected nutrient intake and bone density of young independent-living women and competitive athletic women

RELATIONSHIP BETWEEN SELECTED NUTRIENT INTAKE AND BONE DENSITY OF YOUNG INDEPENDENT-LIVING WOMEN AND COMPETITIVE ATHLETIC WOMEN. TL Taylor, RD, MJ Lucas, EdS,MS,RD, and RG Robinson, MD, Department of Dietetics & Nutrition and Department of Diagnostic Radiology, University of Kansas Medical Center, Kansas City, KS The purpose of this study was twofold: (1) To determine differences in bone density (BD) of spine, hip, total body and kilocalories and selected nutrient intake over two consecutive months between athletic females (athletes) ages 18-28 years and age and height matched healthy, independent-living, nonpregnant, and nonathletic females (controls); and (2) To determine the relationships of single time measurement in BD of spine, hip and total body with usual intake of kilocalories, protein, calcium, phosphorus, vitamins A, C and D for both female groups. Eighteen women met the established criteria for athletes and fifteen for matched controls. Percentage intake of estimated kilocalorie needs and Recommended Dietary Allowances (RDAs) for the six nutrients were determined by analysis of three four-day food intake records. The BD calculations were obtained from single BD measurements of spine, hip and total body by Dual-Energy X-Ray Absorptiometry (DEXA). Mean hip BD, 1.05 g/cm2 vs 0.98 g/cm2, and mean total body BD, 1.17 g/cm2 vs 1.11 g/cm2, were significantly different (p <0.05) for athletes and controls respectively. Statistical significance between groups was found by Hotelling's T Square for Paired Comparisons for hip (p=0.04) and total body (p=0.01) BD. No significant differences were found by ANOVA for repeated measures between groups or over time for usual intake of kilocalories, protein, calcium, phosphorus, vitamins A, C and D, respectively. Three correlation matrices were utilized to determine the relationships among the athletes, the controls, and the total group with respect to all BD and nutrient intake variables. Vitamin A and hip BD correlated significantly (p < 0.05) in all three matrices and calcium and total body BD were significant (p=0.02) for the controls. Nutrient intake did not differ significantly between the athletes and controls. However, differences in BD between the athletes and controls support the positive effects of mechanical loading in cortical bone of the appendicular skeleton. EATING PATERNS PREDICT HEALTH RISK FACTORS IN YOUNG WOMEN. H Zahrt, BJ Scott, RL Brunner and ST St.Jeor, Nutrition Education and Research Program, University of Nevada School of Medicine, Reno, NV There are certain risk factors known to contribute to increased risk for development of chronic disease. Most studies have tended to focus primarily on quantitative aspects of dietary intake by obtaining nutrient amounts. In addition, qualitative aspects of dietary behavior' such as frequency, time and location of meals and snacks and types of food choices can also be assessed from detailed food intake records. The purpose of this study was to examine the relationship between selected health risk factors and two behavioral factors: calories (Kcal) consumed after 5 PM and Kcal consumed from food choices outside of the 'basic' food groups. Subjects for this study (n = 20) were healthy adult women participating in the Reno Diet Heart Study (mean age = 26.45+2.46 years.) Anthropometric measurements were taken and instructions given for recording a complete and detailed record of food intake for 7 days. Upon completion, dietitians reviewed and clarified the food records with the subjects. Dietary data were then analyzed using the USDA standard reference tables. Food records were further analyzed to determine number of meals, Kcal after 5 pm., and Kcal from 'other' foods. The foods in the 'other' category were grouped primarily because of high fat and concentrated sugar or alcohol content, and included foods such as pastries, fried snacks, salad dressing, soft drinks, oils and alcoholic beverages. Mean daily values for the variables of dietary intake were: total Kcal = 2100+509; Kcal after 5 pm 861+319; % of Kcal after 5 pm = 40.7+11.6; Kcal from other foods = 700+317; % Kcal from other foods = 32.2+11.1; total grams of fat = 85.8+28.6; % Kcal from fat= 36.2+6.,9; and mg cholesterol = 283+121. Obesity risk factor values (mean + standard deviation) for the sample were: weight = 158.7+38.7 lb.; % body fat = 31.8+9.1; waist:hip ratio = .76+.05; and BMI = 26.9+5.9. Correlations of behavioral aspects of dietary intake and risk factors were significant between both Kcal and % Kcal from other foods and each of the following: body weight (r=.51 & .55, p<.05), BMI (r=.54 & .54, p<.05), total dietary fat (r=.87 & .68, p<.01), % dietary fat (r=.64 & .71, p<. 01 ) and dietary cholesterol (r.58, p<.01 and r=.47, p<.05). Finally, Kcal after 5pm was correlated with dietary fat (r=.55, p<.01). In summary, a diet higher in calorie dense and/or fatty foods was associated with increased body weight and dietary fat, and a higher number of calories consumed after 5pm was associated with higher total dietary fat intake. The results support the hypothesis that examination of behavioral and quality aspects of the diet may improve understanding of important disease risk factors.