Vitamin D intake and lung cancer risk in the Women’s Health Initiative

Abstract

Background: Prior research suggests that vitamin D protects against lung cancer only among certain subgroups. Objectives: We investigated whether vitamin D intake was associated with lung cancer and explored whether vitamin A intake modified the association. Baseline total intake included both dietary intake (from food-frequency questionnaires) and supplement intake (from bottle labels). HRs were estimated by Cox proportional hazard models. Results: No significant association was observed overall. Among never smokers, a total vitamin D intake $400 IU/d was significantly associated with lower risks of lung cancer (HR: 0.37; 95% CI: 0.18, 0.77 for $800 compared with ,100 IU/d; P-trend = 0.01). No significant effect modification of total vitamin A intake on the association between total vitamin D intake and lung cancer was found. However, the Calcium/Vitamin D Trial active intervention was significantly associated with a lower lung cancer risk only among women with a vitamin A intake ,1000 mg/d retinol activity equivalents (HR: 0.69; 95% CI: 0.50, 0.96; P-interaction = 0.09). Conclusions: Vitamin D intake was associated with a lower lung cancer risk in never-smoking, postmenopausal women. Lower vitamin A intake may be important for a beneficial association of 1 g Ca + 400 IU vitamin D 3 supplementation with lung cancer. This trial was registered at clinicaltrials.gov as NCT00000611.Am J Clin Nutr 2013;98:1002-11.

Serum 25-hydroxyvitamin D concentrations and lung cancer risk in never-smoking postmenopausal women

“…Our findings on high versus deficient levels of serum 25(OH)D are in the same direction as a prospective cohort study in the WHI reporting an inverse association of estimated dietary vitamin D exposure with lung cancer risk in never smokers [40]. The majority of lung cancer cases in these two studies were the same group of women.…”

“…The majority of lung cancer cases in these two studies were the same group of women. The dietary vitamin D study showed that a higher total vitamin D intake (food+supplements) starting from 600 IU/day was significantly associated with a lower risk of lung cancer among never smokers (HR=0.55 [95% CI=0.31-0.96] for 600 to <800 [41 cases] vs. <100 IU/day; HR=0.37 [95% CI=0.18-0.77] for ≥800 [14 cases] vs. <100 IU/day) [40]. Significant inverse associations were also observed for both NSCLC and adenocarcinoma.…”

Vitamin D and Lung Cancer Risk: A Comprehensive Review and Meta-Analysis

“…After an initial screening of retrieved abstracts, 14 papers were preliminarily considered for inclusion in the meta-analysis [11][12][13][14][15][16][17][18][19][26][27][28][29][30]. After applying inclusion criteria, two papers were further excluded [29,30], and 12 studies were finally included into the meta-analysis [11][12][13][14][15][16][17][18][19][26][27][28]. Among those 12 studies, 9 studies were prospective cohort studies [11, 13-15, 17-19, 26, 28], and 3 were nested case-control studies [12,16,27].…”

Vitamin D and Human Reproduction

“…There is accumulating evidence suggesting that the low level of vitamin D is one of important risk factors for cancer and cancer-related mortality [231]. High 25(OH)D levels are related to reduction in mortality in patients suffering from colon, lung, and breast cancer [232,233]. The underlying pathophysiology is not completely understood, but it is suggested that antiproliferative and apoptotic effects of vitamin D on cancer cells, inhibition of metastatic distribution and tumor invasion, and promotion of sensitivity to radiation and chemotherapy influence on decreased mortality in cancers [233].…”