Whether you cold press it, wait for it to drip, have your faithful cappuccino machine do the dirty work or just drive through your local Starbucks, you’re not alone when it comes to craving that morning cup of Joe.
We’ve heard that coffee is bad for us, and many of us have tried to kick the habit—but it’s not so easy. We’ve also heard that coffee in moderation may also have some healthful benefits.
So, just how much does your morning cup (or two) affect your hormones?
Coffee and Hormones
In 2012, a study of women’s health and caffeine sources rippled through social media when it announced preliminary findings that indicated coffee could actually influence hormones in a woman’s body. That small NIH study followed just 259 women for two menstrual cycles to see what would happen to their hormone concentrations, but the answers were surprising.
When women consumed less than 200 mg of caffeine from coffee per day, white women showed significant drops in levels of free estradiol, the primary female sex hormone. Asian women, on the other hand, saw significant rises in free estradiol, even with less than 200 mg of consumption. Caffeinated soda and green tea were also studied, and more than a cup a day of either resulted in higher concentrations of the hormone for all races. It would seem that for white women in this study, a low concentration of coffee could be protective against breast cancer, ovarian cancer and endometrial cancer
At the time, people and news outlets were eager to draw longer-term conclusions from the team’s findings, even though their monitoring was for only two months of each test subject’s life. The NIH emphasized the short-term nature of their work, but of course, results like these couldn’t be ignored and more work soon followed.
“The results indicate that caffeine consumption among women of childbearing age influences estrogen levels,” explained Enrique Schisterman, Ph.D., of the Division of Epidemiology, Statistics and Prevention Research at the Eunice Kennedy Shriver National Institute of Child Health and Human Development, in an interview with the NIH.
“We know that variations in estrogen level are associated with such disorders as endometriosis, osteoporosis, and endometrial, breast, and ovarian cancers. Because long term caffeine consumption has the potential to influence estrogen levels over a long period of time, it makes sense to take caffeine consumption into account when designing studies to understand these disorders,” Dr. Schisterman added.
Endometrial Cancer and Coffee Intake
By 2015, more promising studies were telling women it might be ok to drink more coffee and this time there was no difference noted between racial groups.
Dr. Melissa Merritt led a study that utilized three massive databases to locate women who had been diagnosed with endometrial cancer. Eighty-four different foods and nutrients were traced across the same population in an attempt to correlate eating habits with cases of endometrial cancer.
These scientists concluded that coffee seemed to correlate with lower risks of endometrial cancer. When the datasets were examined more closely, they appeared to point to a higher level of insulin sensitizing adiponectin and sex-hormone binding globulin among the coffee drinkers. But wait, there’s more! It didn’t seem to matter if those coffee-drinkers were drinking regular or unleaded, both correlated with fewer cases of endometrial cancer.
Although correlation doesn’t imply causation, it seems that drinking coffee could affect health well beyond the initial caffeine boost. This isn’t carte blanche permission to dive into your nearest coffee shop and guzzle some fancy coffee, but there may be some value in having a cup or two of decaf in the morning. For now, there’s probably not enough evidence to encourage women who aren’t already drinking coffee to start, but women who already have a coffee habit may find they’re not losing much when switching to decaf. Caffeine isn’t the key here, the compounds in coffee seem to be.
Just remember, all things in moderation, even decaf coffee!