Unveiled connection between vitamin D and contraceptive medication
The Link Between Birth Control and Vitamin D
Let's dive into an intriguing study that discovered women using estrogen-based birth control pill have higher vitamin D levels, while those who stop taking them experience a significant drop.
Vitamin D, a vital nutrient, ensures the correct balance of calcium and phosphorous in the blood, and aids in the body's absorption of calcium, an essential component of bones. Primarily found in foods like fish and eggs, 90% of our vitamin D is produced through a chemical reaction in the skin after sun exposure.
Vitamin D deficiency can lead to serious health issues like rickets and osteomalacia, where bones soften. Given its role in bone formation, it plays a crucial part during pregnancy, especially due to the increased risk of vitamin D deficiency and the subsequent risk of developing bone issues.
Curious to examine any changes in vitamin D levels associated with taking oral contraceptives, Dr. Quaker E. Harmon, from the National Institutes of Health's National Institute of Environmental Health Sciences in Research Triangle Park, NC, led a study.
The Connection Between Contraception and Vitamin D
The researchers conducted a cross-sectional analysis of data from the Study of Environment, Lifestyle, and Fibroids (SELF), which investigated reproductive health. They studied nearly 1,700 African-American women aged 23-34 living in and around Detroit, MI.
Questions about contraceptive use and sun exposure, along with information about vitamin D supplements, were asked. Blood samples were collected from 1,662 women to determine their 25-hydroxy vitamin D levels, the most common circulating form of vitamin D.
Pregnant women produce increased amounts of the active form of vitamin D to support fetal skeleton growth, raising their risk of vitamin D deficiency. Consequently, they face a heightened risk of developing bone problems.
"Our study found that women who were using contraception containing estrogen tended to have higher vitamin D levels than other women," remarked Dr. Harmon.
After accounting for confounding factors like seasonal light exposure, the effect remained significant. "We could not find any behavioral differences to explain the increase," said Dr. Harmon. "Our findings suggest that contraceptives containing estrogen tend to boost vitamin D levels, and those levels are likely to fall when women cease using contraception."
Adjusting for confounding variables, the use of contraceptive pills, patches, or rings containing estrogen was associated with 20 percent higher levels of 25-hydroxy vitamin D. Current users of birth control had higher vitamin D levels, while past users had average levels.
Vitamin D Deficiency in Early Pregnancy
The findings, published in the Journal of Clinical Endocrinology & Metabolism, raise concerns about vitamin D deficiency during early pregnancy, a critical period for fetal development. 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 mechanism behind estrogen-based contraception's impact on vitamin D levels, to which she replied, "We do not know why vitamin D levels are higher. Other work suggests that estrogen in contraceptives may stimulate the synthesis or alter the metabolism of vitamin D. Further research is required."
The current study focused solely on African-American women, and Medical News Today questioned whether race plays a role in the effect. Dr. Harmon responded, "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 likely to be vitamin D-deficient, so small increases or decreases in their vitamin D concentrations may be more important."
Dr. Harmon is continuing to follow the group of women in long-term studies to further investigate the relationship and is also working on another group to explore how vitamin D varies across the menstrual cycle. To learn more about research linking higher vitamin D levels to lower cancer risks, check out our article on the topic.
- Women on estrogen-based birth control pills have higher vitamin D levels compared to those who stop taking them.
- Vitamin D plays a crucial role in the balance of calcium and phosphorous in the blood, and aids in the body's absorption of calcium, an essential component of bones.
- Deficiency in vitamin D can lead to serious health issues like rickets and osteomalacia, where bones soften.
- During pregnancy, vitamin D plays a crucial part due to the increased risk of vitamin D deficiency and the subsequent risk of developing bone issues.
- In a study by Dr. Quaker E. Harmon, it was found that contraceptives containing estrogen tend to boost vitamin D levels, and those levels are likely to fall when women cease using contraception.
- The use of contraceptive pills, patches, or rings containing estrogen was associated with 20 percent higher levels of 25-hydroxy vitamin D.
- The findings raise concerns about vitamin D deficiency during early pregnancy, a critical period for fetal development, and advise that women who are planning to stop using birth control should take steps to ensure adequate vitamin D levels while trying to conceive and during pregnancy.
- Further research is required to understand the mechanism behind estrogen-based contraception's impact on vitamin D levels, and whether this association is related to race or not.
