title: High vitamin C intake is associated with lower 4-year bone loss in elderly men.
abstract: Vitamin C is essential for collagen formation and normal bone development. We evaluated associations of total, supplemental, and dietary vitamin C intake with bone mineral density (BMD) at the hip [femoral neck, trochanter], spine, and radial shaft and 4-y BMD change in elderly participants from the Framingham Osteoporosis Study. Energy-adjusted vitamin C intakes were estimated from the Willett FFQ in 1988-89. Mean BMD and 4-y BMD change was estimated, for men and women, by tertile/category of vitamin C intake, adjusting for covariates. We tested for interaction with smoking, calcium, and vitamin E intake. Among 334 men and 540 women, the mean age was 75 y and mean vitamin D intake was 8.25 mug/d (women) and 8.05 mug/d (men). We observed negative associations between total and supplemental vitamin C intake and trochanter-BMD among current male smokers (P-trend = 0.01). Among male nonsmokers, total vitamin C intake was positively associated with femoral neck BMD (P-trend = 0.04). Higher total vitamin C intake was associated with less femoral neck and trochanter-BMD loss in men with low calcium (all P-trend </= 0.03) or vitamin E intakes (all P-trend = 0.03). Higher dietary vitamin C intake tended to be associated with lower femoral neck-BMD loss (P-trend = 0.09). These associations were attenuated but retained borderline significance (P-trend < 0.1) after adjusting for potassium intake (a marker of fruit and vegetable intake), suggesting that vitamin C effects may not be separated from other protective factors in fruit and vegetables. Null associations were observed among women. These results suggest a possible protective role of vitamin C for bone health in older men.
authors.affiliation: Dietary Assessment and Epidemiology Research Program, Jean Mayer USDA Human Nutrition Research Center on Aging at Tufts University, Boston, MA 02111, USA.
authors.forename: Shivani
authors.initials: S
authors.lastname: Sahni
authors.forename: Marian T
authors.initials: MT
authors.lastname: Hannan
authors.forename: David
authors.initials: D
authors.lastname: Gagnon
authors.forename: Jeffrey
authors.initials: J
authors.lastname: Blumberg
authors.forename: L Adrienne
authors.initials: LA
authors.lastname: Cupples
authors.forename: Douglas P
authors.initials: DP
authors.lastname: Kiel
authors.forename: Katherine L
authors.initials: KL
authors.lastname: Tucker
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D001205:Ascorbic Acid / Q000627:therapeutic use*; D015992:Body Mass Index; D015331:Cohort Studies; D004305:Dose-Response Relationship, Drug; D005260:Female; D005638:Fruit; D006801:Humans; D008297:Male; D008404:Massachusetts; D008875:Middle Aged; D010024:Osteoporosis / Q000517:prevention & control*; D012621:Seasons; D014675:Vegetables
chemical_list: D001205:Ascorbic Acid