There is currently no firm evidence that vitamin D supplementation decreases or increases cancer occurrence in predominantly elderly community-dwelling women .
Vitamin D₃ supplementation  decreased cancer mortality  and vitamin D supplementation  decreased all-cause mortality , but these estimates are at risk of type I errors due to the fact that too few participants were examined , and to risks of attrition bias originating from substantial dropout of participants .
Combined vitamin D₃ and calcium supplements  increased nephrolithiasis , whereas it remains unclear from the included trials whether vitamin D₃ , calcium , or both were responsible for this effect .
BACKGROUND The evidence on whether vitamin D supplementation is effective in decreasing cancers is contradictory .
OBJECTIVES To assess the beneficial and harmful effects of vitamin D supplementation for prevention of cancer in adults .
Relation of androgen receptor gene polymorphism to bone mineral density and fracture risk in early postmenopausal women during a 5-year randomized hormone replacement therapy trial.
In women , the influence of and rogens on bone health is not clear . It has been suggested that the and rogen receptor ( AR ) genotype is associated with bone mineral density and serum and rogen levels in pre- and perimenopausal women , but the association between AR genotype , bone mineral density , and fracture risk has not been studied in postmenopausal women . Therefore , we studied whether AR polymorphism affects bone mineral density , bone mineral density change , or fracture risk in a 5-year r and omized hormone replacement therapy ( HRT ) trial on 331 early postmenopausal women ( mean baseline age , 52.7 + /- 2.3 years ) . The participants consisted of two treatment groups : the HRT group ( n = 151 ) received a sequential combination of 2 mg estradiol valerate and 1 mg cyproterone acetate with or without vitamin D3 , 100 - 300 IU + 93 mg calcium as lactate/day , and the non-HRT group ( n = 180 ) received 93 mg calcium alone or in combination with vitamin D3 , 100 - 300 IU/day for 5 years .  Bone mineral density was measured from lumbar spine and proximal femur ( DXA ) before and after the 5-year trial . All new symptomatic , radiographically defined fractures were recorded during the follow-up . The length of CAG repeat in exon 1 of AR gene was evaluated after polymerase chain reaction ( PCR ) amplification . The subjects were divided into three repeat groups according to AR alleles . None of the baseline characteristics were associated with AR gene polymorphism and HRT treatment . The polymorphism did not influence the calculated annual changes of lumbar or femoral neck bone mineral density during the 5-year follow-up in the HRT ( p = 0.926 and 0.146 , respectively ) or non-HRT ( p = 0.818 and 0.917 , respectively ) groups . In all , 28 women sustained 33 fractures during the follow-up . Thus , the numbers of fractures were limited . The AR repeat length variation was not significantly associated with fracture risk in the HRT or non-HRT groups ( p = 0.632 and 0.459 , respectively ; Cox proportional hazards model ) . In conclusion , AR gene polymorphism was not associated with baseline bone mineral density , 5-year bone mineral density change , or fracture risk in early postmenopausal Finnish women
There is currently no firm evidence that vitamin D supplementation decreases or increases cancer occurrence in predominantly elderly community-dwelling women .
Vitamin D₃ supplementation  decreased cancer mortality  and vitamin D supplementation  decreased all-cause mortality , but these estimates are at risk of type I errors due to the fact that too few participants were examined , and to risks of attrition bias originating from substantial dropout of participants .
Combined vitamin D₃ and calcium supplements  increased nephrolithiasis , whereas it remains unclear from the included trials whether vitamin D₃ , calcium , or both were responsible for this effect .
BACKGROUND The evidence on whether vitamin D supplementation is effective in decreasing cancers is contradictory .
OBJECTIVES To assess the beneficial and harmful effects of vitamin D supplementation for prevention of cancer in adults .