Rise in Vitamin D Levels Among Women Using Estrogen-Based Birth Control
Unveiled connection between vitamin D and contraceptives revealed
A study led by Dr. Quaker E. Harmon of the National Institutes of Health's National Institute of Environmental Health Sciences in Research Triangle Park, NC, has discovered a connection between estrogen-based birth control pills and increased levels of circulating vitamin D. The reverse is also true—women who cease using these contraceptives may experience a significant drop in vitamin D levels.
Vitamin D serves a vital role in maintaining proper calcium and phosphorus levels in the blood and supporting the body's absorption of calcium, an essential component of bones. Rich sources of vitamin D include fish, eggs, and sunlight. However, approximately 90% of vitamin D is produced in the skin following exposure to sunlight.
Vitamin D deficiency can lead to serious conditions such as rickets and osteomalacia (softening of the bones). Due to its importance in bone development, it is particularly critical during pregnancy. The study aimed to investigate whether any changes in vitamin D levels were associated with the use of oral contraceptives.
The researchers conducted a cross-sectional analysis of data from the Study of Environment, Lifestyle, and Fibroids (SELF), which focuses on reproductive health. Almost 1,700 African-American women aged 23-34 residing in and around Detroit, MI, were involved in the study. The women were asked about their contraceptive use, time spent outside, and any vitamin D supplements they took.
Blood samples from 1,662 participating women were used to assess levels of 25-hydroxy vitamin D, the most common circulating form of vitamin D. The findings showed that women using contraception containing estrogen tended to have higher vitamin D levels than other women.
Factors such as seasonal exposure to light were controlled in the analysis, and the effect remained significant. Dr. Harmon explained that no behavioral differences, such as increased time spent outdoors, could be found to explain the increase in vitamin D levels.
After adjusting for confounding variables, the use of contraceptive pills, patches, or rings containing estrogen was associated with a 20% increase in 25-hydroxy vitamin D levels. Both current and past users of birth control showed higher levels of vitamin D.
The study's findings could impact women planning to conceive or those already pregnant. Dr. Harmon advises, "For women planning to stop using birth control, it is worth taking steps to ensure adequate vitamin D levels while trying to conceive and during pregnancy."
Researchers are unsure why estrogen-based contraception might impact vitamin D levels. Further investigation is needed to determine the exact mechanism behind this association. It is also unclear whether this association is consistent across different races, as the study focused solely on African-American women. Nonetheless, further research will be conducted to better understand this issue.
- Women who use estrogen-based birth control may experience increased levels of circulating vitamin D, which plays a crucial role in maintaining proper calcium and phosphorus levels in the blood and supporting the body's absorption of calcium, an essential component of bones.
- The study investigating the connection between oral contraceptive use and vitamin D levels involved nearly 1,700 African-American women residing in or around Detroit, MI, and asked about contraceptive use, time spent outdoors, and any vitamin D supplements they took.
- After adjusting for potential confounding variables, the use of contraceptive pills, patches, or rings containing estrogen was associated with a 20% increase in 25-hydroxy vitamin D levels among the participating women.
- Both current and past users of birth control showed higher levels of vitamin D, suggesting a potential long-term impact of estrogen-based contraception on vitamin D levels.
- The link between estrogen-based contraception and higher vitamin D levels could have implications for women planning to conceive or those who are already pregnant, as vitamin D deficiency can lead to serious conditions such as rickets and osteomalacia.
- Further research is needed to understand the underlying mechanism behind this association and to determine if it is consistent across different races, as the current study focused solely on African-American women. This investigation may provide more insight into the role of nutrients, such as vitamins, in women's health and overall health-and-wellness, as well as the impact of cultural and scientific factors on nutritional needs and deficiencies.
