Estrogen-Based Birth Control Linked to Higher Vitamin D Levels in Women
New findings reveal possible connection between vitamin D and birth control methods.
New research suggests a connection between estrogen-based birth control pills and the levels of vitamin D in women. The study, published in the Journal of Clinical Endocrinology & Metabolism, reveals that women taking these contraceptives have higher quantities of the vital nutrient in their circulation compared to those who do not use such medications.
Women stopping the use of these contraceptives may experience a significant drop in their vitamin D levels, according to Dr. Quaker E. Harmon from the National Institutes of Health's National Institute of Environmental Health Sciences.
Vitamin D plays a significant role in maintaining an optimum balance of calcium and phosphorous in the blood. It also facilitates the absorption of calcium, an essential component for strong bones. Foods like fish and eggs are rich in vitamin D, but around 90% of it is produced naturally in the skin through a chemical reaction triggered by sunlight exposure.
Deficiency in vitamin D can result in rickets and osteomalacia, conditions characterized by softening of the bones. Because of its importance in bone formation, it is particularly crucial during pregnancy.
To investigate whether contraceptive use affects vitamin D levels, Dr. Harmon and her team analyzed data from the Study of Environment, Lifestyle, and Fibroids (SELF). Nearly 1,700 African-American women aged 23-34 living in and around Detroit, MI, were part of the project. The study included information about contraceptive use, time spent outside, and vitamin D supplements, among other factors.
Blood samples were collected from 1,662 women to determine their vitamin D levels, specifically the most common circulating form, called 25-hydroxy vitamin D. Their findings indicate that women using contraception containing estrogen tended to have higher vitamin D levels than others.
Even after accounting for confounding factors such as seasonal exposure to light, the effect remained significant. Dr. Harmon explained that they could not find any behavioral differences to explain the increase. As a result, contraceptives containing estrogen appear to boost vitamin D levels, and those levels decrease when women cease using contraception.
When controlling for confounding variables, the use of contraceptive pills, patches, or rings containing estrogen was associated with approximately 20% higher levels of 25-hydroxy vitamin D. Women currently using these methods had higher vitamin D levels, while past users had average levels.
During pregnancy, women produce increased levels of the active form of vitamin D to support the growth of the fetal skeleton, which may put them at an increased risk of vitamin D deficiency. Dr. Harmon advises that women planning to become pregnant should take measures to ensure adequate vitamin D levels during conception and pregnancy.
When asked about the possible reasons behind this association, Dr. Harmon mentioned that further research is necessary to understand the exact mechanisms linking estrogen and vitamin D metabolism.
The current study focused solely on African-American women. However, the same association has been observed in other racial groups as well. Because of the high incidence of vitamin D deficiency in African-American women, Dr. Harmon believes that even small changes in vitamin D concentration could have more significant effects. The researcher is continuing her work, investigating the relationship further and studying how vitamin D varies across the menstrual cycle.
Maintaining adequate vitamin D levels is crucial for overall health, including bone health and immune function. While more research is needed to fully understand the relationship between estrogen-based contraceptives and vitamin D levels, pregnant women should follow their healthcare providers' guidance regarding vitamin D supplements and lifestyle adjustments.
- The new study, published in the Journal of Clinical Endocrinology & Metabolism, shows that estrogen-based birth control pills lead to higher vitamin D levels in women.
- Women who stop using these contraceptives might experience a significant drop in their vitamin D levels, as suggested by Dr. Quaker E. Harmon from the National Institutes of Health's National Institute of Environmental Health Sciences.
- Vitamin D is essential for maintaining an optimal balance of calcium and phosphorous in the blood and promoting strong bones, as it facilitates calcium absorption.
- Deficiency in vitamin D can lead to rickets and osteomalacia, conditions characterized by softening of the bones, and is particularly crucial during pregnancy due to its significance in bone formation.
- In the Study of Environment, Lifestyle, and Fibroids (SELF), conducted on nearly 1,700 African-American women, it was found that women using contraception containing estrogen had higher vitamin D levels compared to others.
- Dr. Harmon's research shows that, even after accounting for confounding factors, the use of estrogen-containing contraceptives like pills, patches, or rings is associated with around 20% higher levels of the most common circulating form of vitamin D, 25-hydroxy vitamin D.
