The medical community's growing realization that many Americans are low in Vitamin D has led to an explosion of interest in this vitamin's effects on bones, muscle, pregnancy outcomes, cancer risks and other medical concerns.
Vitamin D is a fat-soluble vitamin that aids the absorption of calcium from the GI system. In addition to helping mineralize bone, calcium is important in neuromuscular and immune system function.
Vitamin D is produced in skin that is exposed to sunlight. It naturally occurs in only a few foods, fatty fish and cod liver oil (a hardy few consider cod liver oil to be a food). According to the most recent National Health and Nutrition Examination Survey (NHANES), only 17% of US women get enough vitamin D from food alone.
Most health-conscious women protect their skin from the sun and obtain vitamin D from supplements and vitamin D fortified foods. Recently, I have been including serum vitamin D levels in blood work at annual exams, and have found many of my patients have low vitamin D levels, despite our ongoing discussions about adequate calcium and vitamin D intake.
Other risk factors for vitamin D deficiency besides low sun exposure include being over 50, having darker skin pigmentation and being overweight. Breastfed infants have also been found to be at risk, as adequate vitamin D can't be obtained from human milk alone.
A new paper in the gyn literature looked at how vitamin D levels relate to women's risks for pelvic floor disorders — urinary and rectal incontinence and pelvic organ prolapse. In the NHANES data, results from 1,881 women 20 and older included information on pelvic floor disorders and vitamin D.
The mean age of the surveyed women was 47.9 and more than 80% had suboptimal vitamin D levels. 23% reported symptoms of a pelvic floor disorder. Higher vitamin D levels were associated with a lower rate of pelvic floor disorders. The strongest inverse association was in women over 50 with urinary incontinence. The authors conclude
Given the increase in the number of patients with pelvic floor disorders, further evaluation of the role of vitamin D is warranted, particularly future research to assess the relationship between vitamin D levels and pelvic muscle strength in women of all ages and racial/ethnic groups. Our findings suggest that treatment of vitamin D insufficiency and deficiency in both premenopausal and postmenopausal women could improve pelvic muscle strength, with a possible reduction in the prevalence of pelvic floor disorders including urinary incontinence.
It is encouraging to think that the hugely annoying problem of urinary incontinence could be improved by something as simple as supplementing vitamin D. If you have not had your vitamin D level checked, it is worth doing at your next annual exam. If you have problems with urinary incontinence, it may be worthwhile having it checked sooner.