Washington: Black women with high intake of dairy products have a reduced
incidence of uterine leiomyomata (fibroids), say researchers.
Boston University School of Medicine (BUSM) researchers at the Slone
Epidemiology Center reported the finding in the current issue of the American
Journal of Epidemiology.
Uterine fibroids are benign tumors of the uterus and are two to three times more
common among black women than white women. They are the primary indication for
hysterectomy in the US.
National surveys show that black women consume fewer servings of dairy than
white women and have lower intake of calcium, magnesium and phosphorus. The
causes of fibroids are poorly understood, but sex steroid hormones and growth
factors are thought to play a role. The Slone researchers studied dairy products
because of the possibility that they have antioxidant effects and may modify
endogenous sex hormones.
The study was based on data from the Black Women's Health Study. The 59,000
study participants, enrolled in 1995, completed biennial questionnaires on which
they reported whether they were diagnosed with fibroids. Their diet was assessed
at two points in time using a modified version of the National Cancer
Institute's Block short-form food frequency questionnaire (FFQ).
Based on 5,871 incident cases of fibroids diagnosed after 10 years of follow-up,
the study found that high dairy intake was inversely associated with fibroid
risk after controlling for other risk factors. Fibroid incidence was reduced by
30% among women who had 4 or more dairy servings a day, relative to women who
had less than 1 serving a day. Intakes of calcium, phosphorus, and
calcium-to-phosphorus ratio (an indicator of calcium bioavailability) were also
inversely associated with fibroid risk.
Because dairy intake is lower among blacks than whites, such differences in
intake may contribute to the racial discrepancy in rates of fibroids.
"Although the exact mechanisms are unclear, a protective effect of dairy
consumption on uterine fibroids risk is plausible, as calcium, a major component
of dairy foods, may reduce cell proliferation," said lead author Lauren A Wise,
ScD, an associate professor of epidemiology at Boston University School of
Public Health and a senior epidemiologist at the Slone Epidemiology Center at
BUSM.
"This is the first report showing an inverse association between dairy intake
and fibroid risk. If confirmed, a modifiable risk factor for fibroids, a major
source of gynecologic morbidity, will have been identified," added Wise.
Source : DNA
