Study suggests calcium, vitamin D helps postmenopausal women lower cholesterol

CLEVELAND, Ohio — A new study suggests that calcium and vitamin D supplements after menopause can improve women's cholesterol profiles, and much of that effect is tied to raising vitamin D levels.



The study is from the Women's Health Initiative and was recently published online in Menopause, the journal of the North American Menopause Society.



The study, "Calcium/vitamin D supplementation, serum 25-hydroxyvitamin D concentrations and cholesterol profiles in the Women's Health Initiative calcium/vitamin D randomized trial," will be published in the August 2014 print edition of Menopause.



Whether calcium or vitamin D can indeed improve cholesterol levels has been debated. Studies of women taking the combination could not separate the effects of calcium from those of vitamin D on cholesterol. However, this study, led by NAMS board of trustees member Peter Schnatz is helping to settle those questions because it looked both at how a calcium and vitamin D supplement changed cholesterol levels and how it affected blood levels of vitamin D in postmenopausal women.



Daily, the women in the WHI CaD trial took either a supplement containing 1,000 mg of calcium and 400 IU of vitamin D3 or a placebo. This analysis looked at the relationship between taking supplements and levels of vitamin D and cholesterol in some 600 of the women who had both their cholesterol levels and their vitamin D levels measured.



The women who took the supplement were more than twice as likely to have vitamin D levels of at least 30 ng/mL (i.e., normal according to the Institute of Medicine), as were the women who took the placebo.



Supplement users also had low-density lipoprotein (LDL — the "bad" cholesterol) levels that were between four and five points lower. The investigators discovered, in addition, that among supplement users, those with higher blood levels of vitamin D had higher levels of high-density lipoprotein (HDL — the "good" cholesterol) and lower levels of triglycerides (although for triglycerides to be lower, blood levels of vitamin D had to reach a threshold of about 15 ng/mL).



Taking the calcium and vitamin D supplements was especially helpful in raising vitamin D levels in women who were older, women who had a low intake and women who had levels first measured in the winter. But lifestyle also made a difference. The supplements also did more to raise vitamin D levels in women who did not smoke and who drank less alcohol.



Whether these positive effects of supplemental calcium and vitamin D on cholesterol will translate into such benefits as lower rates of cardiovascular disease for women after menopause remains to be seen, but these results, said the authors, are a good reminder that women at higher risk for vitamin D deficiency should consider taking calcium and vitamin D.