Effects of gender, XXXX , smoking, and dairy consumption on bone mass in Wisconsin adolescents.

@entity167 @entity79 @entity170
INTRODUCTION: Failure to attain peak bone mass during adolescence may be an important contributor to the development of @entity170 . METHODS: This prospective, descriptive study evaluated the relationship between @entity170 risk factors and attainment of bone mass in 239 Wisconsin high school students. Students completed an annual risk assessment questionnaire that included questions about dairy intake, @entity167 use, and smoking. Heel @entity79 ( @entity79 ) was measured in the 9th grade (year 1) and 12th grade (year 4). RESULTS: A total of 109 students were included in the final analysis of a covariance model used to predict year 4 @entity79 . The model included separate year 1 @entity79 slope and intercept terms for males and females and indicator variables for adequate dairy intake and combined @entity167 habits or smoking habits (overall P<0.001, multiple r2=0.871). The predicted year 4 @entity79 for females was 0.07 g/cm2 plus 85.6% of their year 1 @entity79 . For males, predicted year 4 @entity79 was 0.008 g/cm2 plus 110% of their year 1 @entity79 . Self-reported dairy intake of > or = 4 servings per day was associated with a 0.032 g/cm2 increase in @entity79 , while self-reported smoking or @entity167 use was associated with a decrease in @entity79 of 0.028 g/cm2. CONCLUSIONS: @entity167 or smoking had a significant negative effect on bone density, whereas adequate dairy intake (>4 servings per day) had a favorable effect in Wisconsin adolescents. Sex differences in bone density growth were clearly identified, with males tending to gain @entity79 and females tending to lose @entity79 by year 4.
