Low levels of vitamin D appear to be connected both to endometriosis onset and to its severity, researchers said in a study that found women with the lowest blood concentrations of the vitamin also had the largest ovarian endometrioma, or ovarian cysts.
The study, “Ovarian endometriosis and vitamin D serum levels,” was published in Gynecological Endocrinology. Its findings suggest that vitamin D supplements could be a safe and low-cost therapeutic approach.
Endometriosis seems to result from a combination of genetic, hormonal, immunological, and environmental factors. Yet, inflammation processes play an important role in the development and progression of the disease.
Vitamin D is known to reduce inflammatory responses, and it has been shown to have regulating effects on the immune system. The potential role of vitamin D in immune diseases is drawing increased interest, and previous studies have found anti-inflammatory effects in diseases such as rheumatoid arthritis and psoriasis, and decreased tumor growth in cancers.
Women with endometriosis tend to have lower vitamin D levels compared to the general population, higher levels of which seem to be associated with a lower risk of getting the disease, according to studies.
A research team investigated the connection between blood levels of vitamin D and the size of cysts in women with ovarian endometriosis. In total, 49 women with a single cyst underwent a gynecological ultrasound and blood test.
Results showed that 42 (86%) of the 49 women were vitamin D (25-OH-D3) deficient. In addition, a relationship was seen between vitamin levels and cyst sizes, with women with the lowest levels having the largest cysts. These findings held even after adjusting for factors such as age, body mass, tobacco use, and their number of pregnancies, which are associated with an increased risk of vitamin D deficiency.
The mechanisms that explain why vitamin D may influence the risk of endometriosis are not yet understood, and it is not clear if vitamin supplements would have any effect. In a previous endometriosis study, rats treated with vitamin D showed reduced cyst size and reduced fibrosis production, but how well these benefits translate to people is yet to be seen.
Further research is clearly needed but, taken together, the results indicate that vitamin D deficiency could play an important role in the development and progression of endometriosis, and may also be connected to disease severity.
“Thus it is possible to speculate that vitamin D supplementation in women with vitamin D deficiency might be a novel, safe and low-cost therapeutic strategy both in the primary prevention and treatment of endometriosis,” the researchers wrote.