Uterine fibroids can occur in women at any age, though they are most common in women between the ages of 30 and 40. Although these tumors are not cancerous, they can cause serious discomfort in women. There is some evidence that caffeine may make fibroids worse in some women, but it is not clear what role, if any, caffeine plays in fibroid formation. Caffeine may also worsen fibroids in the breast.
Uterine fibroids can cause bleeding between periods, unusually long or menstrual bleeding, pelvic cramping, the need to urinate more often, pain during sex and a feeling of pressure or fullness in the abdomen. Although it is not known what causes fibroids to form, their growth is stimulated by estrogen. Consequently, fibroids usually stop growing once a woman stops menstruating.
Caffeine and Estrogen
Since estrogen can cause fibroids to grow, anything that raises estrogen levels in the body might make fibroids worse. According to a study by the National Institutes of Health, conducted from 2005 to 2007, Asian women who consumed the equivalent of more than 200 milligrams of coffee each day had higher estrogen levels than those who didn't. The reverse was true, however, for Caucasian women --- higher caffeine intake was associated with lower estrogen levels. The source of the caffeine also affected estrogen levels. Consumption of more than one cup each day of caffeinated soda or green tea was associated with a higher estrogen level in both Asian and Caucasian women. The study results indicate that caffeine consumption in certain cases is linked to increased estrogen, which makes fibroids worse.
Breast fibroids are rubbery nodules near the surface of the breast that can become painful. Although it is not known what causes these fibroids to form, the fibroids can enlarge and become more painful when you drink substances with caffeine. Drinking lots of water and avoiding fatty foods can also reduce pain from breast fibroids.