Does Caffeine Increase Estrogen

Caffeine is the most widely used mood-altering drug in the world, according to researchers at John Hopkins Bayview Medical Center. Numerous studies have been performed on its mood-altering effects, but several studies have also begun to look at its possible effects on the hormone estrogen, which is a primary female sex hormone. Although men also produce estrogen, the studies have focused on women. While studies have suggested that caffeine does increase estrogen, the effects of that increase have yet to be studied thoroughly.

Basic Interactions

In order to get rid of caffeine, the body breaks it down to basic components. Estrogen inhibits caffeine metabolism, which means the caffeine will not break down in the body as quickly. If you are taking additional estrogen, such as in hormone replacement therapy, you might experience headaches, fast heartbeat and other side effects if you consume coffee.

Increased Estrogen

In a study published in the October 2001 edition of the "Fertility and Sterility" journal, researchers studied 498 women between the ages of 36 and 45 who were not currently pregnant, breastfeeding or taking hormones. They polled the women on their consumption of alcohol and caffeine as well as their use of tobacco. After adjusting for all factors, including age, body mass index, total calories, current smoking, alcohol, cholesterol consumption and day of sampling, the researchers found that participants who consumed more than 100 mg of caffeine a day, about a cup of coffee, had a higher level of estradiol --- a naturally occurring form of estrogen --- during the early follicular phase of their menstrual cycle. Those levels increased by 70 percent in women who consumed more than 500 mg of caffeine a day, or about four to five cups of coffee. The researchers concluded that consuming caffeine, including in the form of coffee, may increase the estradiol levels during the early part of a woman's menstrual cycle independent of tobacco or alcohol use.

Possible Risks

Although studies and data are limited, and sometimes contradictory, increased estrogen may exacerbate issues such as endometriosis, breast pain and breast or ovarian cancer. For example, according to a study published in the October 2008 edition of the "Archives of Internal Medicine," while there was no association between caffeine consumption and breast cancer risk, the possibility that caffeine affected certain types of estrogen-related breast disease and tumors warranted further investigation.

Recommendations

Although studies were limited at the time of publication, and the studies performed have shown mixed results, enough evidence has surfaced to indicate a possible increase in estrogen levels caused by caffeine. If you are taking estrogen, are going through menopause, or have any type of estrogen-related maladies, consult your doctor regarding caffeine consumption.