But according to data from a 2021 study published in Reproductive Sciences, MED12 mutations are more common in Black people (74.5%) compared to white (65.8%) and Asian (53.2%) people.5 It’s known that having a family history of fibroids increases your chances of developing them, but some experts suggest that the MED12 mutation is not hereditary. Meaning, even though it seems like fibroids run in the family, genetics seem to be just one piece of the puzzle.
Exposure to certain chemicals
The well-meaning aunty who told you to “stay away from those relaxers” may be onto something. Phthalates, which can be found in some hair relaxers—straightening products used by millions of Black people in the US—have been connected to uterine fibroids, according to various studies.1,6 The use of these products is also linked to other reproductive health conditions, including breast cancer.7
Phthalates are chemicals that are used to make durable plastics and dissolve other materials, and we’re all exposed to them daily. They’re used in vinyl flooring, lubricating oils, garden houses, and, yes, personal-care products like soaps, shampoos, and hair sprays (in which they’re often stealthily listed as “fragrance” or “perfume” on the ingredients label).
More research is needed to understand the possible link between fibroids and relaxers, but one thing is pretty evident: Studies show Black women use these hair products, many of which contain chemicals that are thought to be hormone-disrupting, at a much higher rate starting at a much younger age than white women—often due to the pressure to conform to racist beauty standards.1
Black folks, according to a 2020 analysis of data from more than 38,000 women, tend to have a higher exposure to phthalates, among other questionable chemicals, in part due to these hair products.7 And when certain phthalates are inhaled or absorbed into the skin, they’ve been shown, at least in rat studies, to potentially act like estrogen in the body, a hormone that is believed to play a role in the growth of fibroids, per the ACOG.
Vitamin D deficiency
While the potential connection between diet and uterine fibroids is complex, a low intake of fruits and vegetables is generally associated with a risk of developing them. Many experts also agree that vitamin D deficiency is a notable risk factor.8 In fact, in one small study published in 2019, researchers found that a vitamin D treatment regimen may shrink fibroids in people who are deficient.9
People with darker skin tend to have a higher incidence of vitamin D deficiency, and not just because increased pigmentation can reduce the skin’s ability to make vitamin D from the sunlight. (Which, by the way, is an oversimplified theory to begin with.)
The reality is, one in five Black households is located in a “food desert,” meaning they live in areas with fewer grocery stores, restaurants, and farmers markets, limiting their ability to eat a well-rounded, nutrient-rich diet. This includes high-quality, affordable foods that naturally contain vitamin D, like fish, eggs, and mushrooms.
According to a study published in the Journal of Epidemiology, kids who get their periods at 11 years old or younger are more likely to eventually develop uterine fibroids. (The researchers wrote that these results were true regardless of race, but it’s worth noting the study’s participant pool was heavily skewed toward white individuals.)10