BACKGROUND: Numerous observational studies have found supplemental calcium and vitamin D to be associated with reduced risk of common cancers. However, interventional studies to test this effect are lacking. OBJECTIVE: The purpose of this analysis was to determine the efficacy of calcium alone and calcium plus vitamin D in reducing incident cancer risk of all types. DESIGN: This was a 4-y, population-based, double-blind, randomized placebo-controlled trial. The primary outcome was fracture incidence, and the principal secondary outcome was cancer incidence. The subjects were 1179 community-dwelling women randomly selected from the population of healthy postmenopausal women aged >55 y in a 9-county rural area of Nebraska centered at latitude 41.4 degrees N. Subjects were randomly assigned to receive 1400-1500 mg supplemental calcium/d alone (Ca-only), supplemental calcium plus 1100 IU vitamin D3/d (Ca + D), or placebo. RESULTS: When analyzed by intention to treat, cancer incidence was lower in the Ca + D women than in the placebo control subjects (P < 0.03). With the use of logistic regression, the unadjusted relative risks (RR) of incident cancer in the Ca + D and Ca-only groups were 0.402 (P = 0.01) and 0.532 (P = 0.06), respectively. When analysis was confined to cancers diagnosed after the first 12 mo, RR for the Ca + D group fell to 0.232 (CI: 0.09, 0.60; P < 0.005) but did not change significantly for the Ca-only group. In multiple logistic regression models, both treatment and serum 25-hydroxyvitamin D concentrations were significant, independent predictors of cancer risk. CONCLUSIONS: Improving calcium and vitamin D nutritional status substantially reduces all-cancer risk in postmenopausal women. This trial was registered at clinicaltrials.gov as NCT00352170.
RCT Entities:
BACKGROUND: Numerous observational studies have found supplemental calcium and vitamin D to be associated with reduced risk of common cancers. However, interventional studies to test this effect are lacking. OBJECTIVE: The purpose of this analysis was to determine the efficacy of calcium alone and calcium plus vitamin D in reducing incident cancer risk of all types. DESIGN: This was a 4-y, population-based, double-blind, randomized placebo-controlled trial. The primary outcome was fracture incidence, and the principal secondary outcome was cancer incidence. The subjects were 1179 community-dwelling women randomly selected from the population of healthy postmenopausal women aged >55 y in a 9-county rural area of Nebraska centered at latitude 41.4 degrees N. Subjects were randomly assigned to receive 1400-1500 mg supplemental calcium/d alone (Ca-only), supplemental calcium plus 1100 IU vitamin D3/d (Ca + D), or placebo. RESULTS: When analyzed by intention to treat, cancer incidence was lower in the Ca + Dwomen than in the placebo control subjects (P < 0.03). With the use of logistic regression, the unadjusted relative risks (RR) of incident cancer in the Ca + D and Ca-only groups were 0.402 (P = 0.01) and 0.532 (P = 0.06), respectively. When analysis was confined to cancers diagnosed after the first 12 mo, RR for the Ca + D group fell to 0.232 (CI: 0.09, 0.60; P < 0.005) but did not change significantly for the Ca-only group. In multiple logistic regression models, both treatment and serum 25-hydroxyvitamin D concentrations were significant, independent predictors of cancer risk. CONCLUSIONS: Improving calcium and vitamin D nutritional status substantially reduces all-cancer risk in postmenopausal women. This trial was registered at clinicaltrials.gov as NCT00352170.
Authors: Karen W Phinney; Mary Bedner; Susan S-C Tai; Veronica V Vamathevan; Lane C Sander; Katherine E Sharpless; Stephen A Wise; James H Yen; Rosemary L Schleicher; Madhulika Chaudhary-Webb; Christine M Pfeiffer; Joseph M Betz; Paul M Coates; Mary Frances Picciano Journal: Anal Chem Date: 2011-12-28 Impact factor: 6.986
Authors: María Elena Martínez; Elizabeth T Jacobs; John A Baron; James R Marshall; Tim Byers Journal: J Natl Cancer Inst Date: 2012-04-25 Impact factor: 13.506
Authors: David A Hanley; Ann Cranney; Glenville Jones; Susan J Whiting; William D Leslie; David E C Cole; Stephanie A Atkinson; Robert G Josse; Sidney Feldman; Gregory A Kline; Cheryl Rosen Journal: CMAJ Date: 2010-07-12 Impact factor: 8.262
Authors: Stephanie J Weinstein; Mark P Purdue; Stephanie A Smith-Warner; Alison M Mondul; Amanda Black; Jiyoung Ahn; Wen-Yi Huang; Ronald L Horst; William Kopp; Helen Rager; Regina G Ziegler; Demetrius Albanes Journal: Int J Cancer Date: 2014-09-02 Impact factor: 7.396