Uncovered tie between vitamin D and contraception: new findings suggest a potentially significant correlation
Rewritten Article:
Let's dive into a fascinating finding by researchers – women who take estrogen-based birth control pills have higher levels of circulating vitamin D, while those who cease using these contraceptives experience a significant drop in vitamin D levels.
Vitamin D serves a crucial role in maintaining the appropriate levels of calcium and phosphorus in the blood, and it aids in the body's absorption of calcium, a vital component of bones. While food sources like fish and eggs are loaded with vitamin D, approximately 90% of this essential nutrient is produced within the skin via a chemical reaction triggered by sun exposure.
Deficiency in vitamin D can lead to rickets and osteomalacia, conditions characterized by softening of the bones. Given its importance in bone formation, it's particularly crucial during pregnancy. Researcher, Dr. Quaker E. Harmon from the National Institutes of Health's National Institute of Environmental Health Sciences in Research Triangle Park, NC, decided to investigate changes in vitamin D levels associated with taking oral contraceptives.
Vitamin D and Contraception
Dr. Harmon and his team carried out a cross-sectional analysis by studying the reproductive health of African-American women aged 23-34 in and around Detroit, MI. These women were participating in the Study of Environment, Lifestyle, and Fibroids (SELF). The researchers gathered information about the women's contraceptive use, their outdoor time, and any vitamin D supplements they took.
Blood samples were collected from a total of 1,662 women to assess their levels of the most common form of circulating vitamin D, known as 25-hydroxy vitamin D. During pregnancy, women produce higher levels of the active form of vitamin D to support the growth of the fetal skeleton. Thus, pregnant women are at a heightened risk of vitamin D deficiency, which increases their likelihood of developing bone problems.
"Our study found that women using contraception containing estrogen tended to have higher vitamin D levels than other women," shared Dr. Harmon. Even after controlling for factors like seasonal exposure to light, the effect remained significant. Dr. Harmon mentioned, "We could not find any behavioral differences such as increased time spent outdoors to explain the increase."
After adjusting for confounding variables, the use of contraceptive pills, patches, or rings containing estrogen was associated with a 20% increase in levels of 25-hydroxy vitamin D. Interestingly, current users of birth control had higher vitamin D levels, while past users displayed average levels.
Vitamin D Deficiency in Early Pregnancy
These findings, published in the Journal of Clinical Endocrinology & Metabolism, suggest that women who plan to conceive may be at risk of vitamin D deficiency as they stop using birth control. Dr. Harmon advises, "For women who are planning to stop using birth control, it is worth taking steps to ensure that vitamin D levels are adequate while trying to conceive and during pregnancy."
Medical News Today asked Dr. Harmon about the reasons behind estrogen-based contraception affecting vitamin D levels. She added, "We do not know why vitamin D levels are higher. Other work suggests that the levels of other vitamin D metabolites are altered when women use estrogen-containing contraception, which hints at changes in the metabolism of vitamin D. Further research is needed."
The study focused solely on African-American women. Dr. Harmon clarified, "The same association has been observed in young and older women who are not African-American, so we believe this association is not related to race. In the United States, African-American women are more prone to vitamin D deficiency, so subtle changes or decreases in their vitamin D concentrations may be more significant."
Dr. Harmon continues to follow this group of women to further investigate the relationship between vitamin D and contraception, as well as collaborating on another study exploring how vitamin D varies throughout the menstrual cycle.
Curious to know more about the link between higher vitamin D levels and lower cancer risk? Check it out!
Enrichment Insights:- Estrogen-based contraceptives can increase circulating vitamin D levels through several pathways, including altering vitamin D metabolism, influencing bone and mineral metabolism, and modulating the vitamin D receptor (VDR). However, the exact mechanisms are yet to be fully understood.- The effect of estrogen-based contraceptives on vitamin D levels may differ by race due to genetic variations related to vitamin D metabolism and receptor expression, as well as environmental factors such as diet and sunlight exposure. Research in this field is limited, and additional studies are needed to fully understand these interactions.
- Women using estrogen-based contraceptives were found to have higher levels of 25-hydroxy vitamin D, a common form of circulating vitamin D, according to a study by Dr. Harmon and his team.
- In the study, African-American women who used estrogen-based birth control showed a significant increase in their vitamin D levels, even after controlling for factors like seasonal exposure to light.
- The researchers suggested that the increase in vitamin D levels could be due to changes in the metabolism of vitamin D, but the exact mechanisms are yet to be fully understood.
- For women who are planning to stop using birth control, it is advisable to ensure adequate vitamin D levels while trying to conceive and during pregnancy, as women who cease using these contraceptives may experience a significant drop in vitamin D levels.
- The same association between higher vitamin D levels and estrogen-based contraceptives has been observed in women not of African-American descent, but due to higher rates of vitamin D deficiency in this population, even subtle changes or decreases in vitamin D concentrations may be more significant.
- Dr. Harmon continues to study the relationship between vitamin D and contraception, as well as exploring how vitamin D levels vary throughout the menstrual cycle.
