Uterine fibroids are non-cancerous tumors that originate from the smooth muscle layer of the uterus. Fibroids are the most common benign tumors in women and are usually found during the middle and later reproductive years. While most fibroids are asymptomatic, they can grow and cause heavy and painful menstruation, painful sexual intercourse, urinary frequency, and urinary urgency.
Globally, approximately 235 million people are affected with uterine fibroids. Up to 40% of all women will be diagnosed with fibroids at some point in their life but only a tiny fraction will require treatment. Fibroids are heavily dependent on estrogen and progesterone levels, so they shrink after menopause, female hormone levels go down.
Blacks are anywhere between 2-4 times more likely to get fibroids as Whites. The cost of fibroids exceeds $34 billion per year. A safe and effective oral treatment option for fibroids would have an immense impact on women’s health worldwide.
Doctor Mohamed Sabry and colleagues of Meharry Medical College in Tennessee working under senior author Ayman Al-Hendy of Meharry Medical College just published an important discovery. Uterine fibroids are associated with 25(OH)D levels.
Sabry M, Halder SK, Allah AS, Roshdy E, Rajaratnam V, Al-Hendy A. Serum vitamin D3 level inversely correlates with uterine fibroid volume in different ethnic groups: a cross-sectional observational study. Int J Womens Health. 2013;5:93-100.
The authors had previously shown that vitamin D shrinks fibroid cells in the test tube and that vitamin D safely shrink fibroids in a rat model.
Here, they studied 104 women with fibroids and 50 normal controls. This was a cross sectional study in which all women had their 25(OH)D levels measured and all women had a pelvic ultrasound.
The average level of serum 25(OH)D was lower in fibroid cases (19.7 ng/mL) than in healthy controls (22.3 ng/mL; P = 0.01). Black participants diagnosed with symptomatic fibroids had lower serum 25(OH)D (12.9 ng/mL) than Black healthy controls (18.30 ng/mL; P = 0.05). White participants diagnosed with fibroids had a trend toward lower levels (24.45 ng/mL) than White healthy controls (29.53 ng/ml; P = 0.052).
Also, the larger the fibroids, the lower the vitamin D levels (r = −0.31; P = 0.002). When grouped according to ethnicity, a significant association (r = −0.305; P = 0.001) was found between vitamin D levels and total fibroid volume in the Black participants. In the White participants, the inverse correlation trended towards significant (r = −0.86; P = 0.058).
We need more studies, but if I was a woman with fibroids, I’d take 5,000 IU/day. Of course if I was a woman without fibroids, I’d take the same.