Uncovered Connection: Vitamin D and Hormonal Contraception Revealed
Estrogen in Birth Control May Impact Vitamin D Levels
A recent study by researchers at the National Institutes of Health's National Institute of Environmental Health Sciences in Research Triangle Park, NC, has found a correlation between estrogen-based birth control and vitamin D levels in women.
According to the research, women on estrogen-based contraceptives, such as pills, patches, or rings, tend to have higher levels of vitamin D than those not taking these medications. Conversely, women who stop using estrogen-based birth control experience a significant drop in vitamin D levels.
Vitamin D plays a vital role in maintaining the correct calcium and phosphorous levels in the blood and aiding the body's absorption of calcium, an essential component of bones. Foods high in vitamin D include fish and eggs, but approximately 90 percent of the vitamin is produced in the skin through a chemical reaction triggered by sunlight exposure.
Deficiency in vitamin D can lead to conditions such as rickets and osteomalacia (softening of the bones), particularly during pregnancy, when the active form of vitamin D is vital for the growth of the fetal skeleton.
Dr. Quaker E. Harmon, the study's lead researcher, and her team analyzed data from the Study of Environment, Lifestyle, and Fibroids (SELF), an investigation of reproductive health involving almost 1,700 African-American women living in and around Detroit, MI, aged 23-34. The study asked women about their contraceptive use, time spent outdoors, and any vitamin D supplements they took.
Blood samples were taken from 1,662 women to determine their levels of the most common circulating form of vitamin D, called 25-hydroxy vitamin D. After adjustments for confounding variables, the use of contraceptive pills, patches, or rings containing estrogen was associated with a 20 percent higher level of 25-hydroxy vitamin D.
Current users of birth control had higher levels of vitamin D, while past users had average vitamin D levels. Dr. Harmon advises women planning to stop using birth control to ensure their vitamin D levels are adequate while trying to conceive and during pregnancy.
The study found no compelling evidence of behavioral differences, such as increased time spent outdoors, to explain the increase in vitamin D levels. Dr. Harmon also revealed that estrogen may potentially alter the metabolism of vitamin D, though the precise biological mechanism is not yet fully understood.
The study only looked at African-American women, yet Dr. Harmon believes the association is not race-specific. African-American women in the United States are more likely to be vitamin D deficient, so even small changes in vitamin D concentrations may be more significant for this group. Dr. Harmon continues to follow this group of women to further investigate the relationship between estrogen-based birth control and vitamin D levels and is working on another group of participants to explore how vitamin D varies across the menstrual cycle.
Previous research suggests that estrogen-based contraception may lower vitamin D levels, but consensus is not uniform across different racial and ethnic groups. Future studies are needed to determine whether this effect is consistent or more pronounced in certain populations.
Sources:1. Journal of Clinical Endocrinology & Metabolism2. National Institutes of Health's National Institute of Environmental Health Sciences, Research Triangle Park, NC3. Study of Environment, Lifestyle, and Fibroids (SELF)4. Relevant enrichment data (optional): The enrichment data suggests that estrogen-based contraception may lower vitamin D levels, leading to an increased risk of deficiency, particularly among women with darker skin due to higher melanin content, which impacts sun exposure-dependent vitamin D production. However, the study's focus on African-American women means that more research is needed to confirm whether the effect is consistent across different racial and ethnic populations.
- The correlation between estrogen-based birth control and vitamin D levels in women was revealed in a study by the National Institutes of Health's National Institute of Environmental Health Sciences.
- Women on estrogen-based contraceptives tend to have higher levels of vitamin D than those not taking these medications, as indicated by the study.
- Vitamin D plays a crucial role in maintaining bone health by aiding in the correct calcium and phosphorus levels in the blood and facilitating the body's absorption of calcium.
- Deficiencies in vitamin D can lead to conditions such as rickets and osteomalacia, particularly during pregnancy, when the active form of vitamin D is vital for the growth of the fetal skeleton.
- Dr. Quaker E. Harmon, the study's lead researcher, suggests that women planning to stop using birth control should ensure their vitamin D levels are adequate while trying to conceive and during pregnancy.
- The study's findings indicate that estrogen may potentially alter the metabolism of vitamin D, although the precise biological mechanism is not yet fully understood.
