Caffeine is bad for PMS and PMDD, because it increases stress and anxiety levels. The science on caffeine is confusing, though, because caffeine appears to help with concentration and depression. How can something that makes anxiety worse help with depression and concentration? We have no idea. Anxiety and depression are nearly inseparable—it’s hard to have one without the other. And anxiety tends to interfere with concentration too.
In any case, we’ll stick to our guns, if you’re concerned about PMS and PMDD symptoms, avoid caffeine. You can learn more about how to determine if caffeine affects your symptoms in our food allergy test article.
However, we want to call your attention to yet another confusing bit of research: it turns out that drinking 200 milligrams of caffeine in a day—the amount in 1-2 cups of coffee, or one little red energy drink, or about four cups of tea—will change your estrogen level. The funny thing is, the study, which will be published this week in the American Journal of Clinical Nutrition, shows that the effect of caffeine on estrogen varies depending on your ethnicity.
In white women, caffeine lowered estrogen, whereas in Asian women it raised it. The effect also appears to depend on the source of the caffeine: green tea and caffeinated soda raised estrogen no matter the race of the woman consuming it.
All of this leads us to wonder if perhaps Asian women consume more green tea, and if coffee has some quality that might lower estrogen—a quality that tea and soda, obviously, are missing.
We should point out that this study only looked into women of reproductive age, not menopausal or post-menopausal women. We’d say this qualifies as a very preliminary study: you can’t really draw any health conclusions from it. Unfortunately, many medical research studies leave one with a similarly unsettled feeling, since so often they raise more questions than they answer. On the other hand, over time, research is quite good at revealing truths in health and medicine, as long as that research is conducted and interpreted fairly.