Coffee is often put into the same category as smoking and alcohol consumption as being something that will be harmful to you. Coffee drinking has a history that dates back as far or perhaps further back than the 15th century. Millions of people drink coffee every day to improve their mood, fight fatigue, and enhance concentration.
The active ingredient everyone wants in a cup of coffee is caffeine, a psychostimulant. Some researchers have suggested that it might contribute to heart disease, cancer, infertility, and pregnancy complications. But, are these claims true? Are caffeine and coffee consumption really bad for you?
Some things are true of caffeine that might be worth knowing about, according to Dr. Jorge Chavarro MD, a researcher out of the Departments of Nutrition and Epidemiology at the Harvard School of Public Health:
- There is some evidence, for example, that caffeine will affect the metabolism of estrogen in women who have yet to reach menopause. This might or might not affect fertility.
- Caffeine is also a plant alkaloid that inhibits phosphodiesterase (an enzyme in the cells of the body) making caffeine a natural pesticide that, while it protects plants, can be a neurotoxin in certain primitive herbivores who eat the plants.
Effects of Caffeine in Humans
The good news is that what affects primitive herbivores doesn’t necessarily translate to the modern-day human nervous system and there is no evidence that caffeine has a negative effect on the human brain or its nerves.
Research done in the past indicating that caffeine might be bad for your health didn’t take into account the fact that some coffee drinkers also engage in much more harmful behaviors, such as smoking, which does affect health in a bad way.
The research…
- In 2015, a comprehensive review of caffeine intake was conducted for the Dietary Guidelines for Americans Scientific Advisory Committee indicated that caffeine reduces the risk of heart disease, type 2 diabetes, liver and uterine cancer, and early deaths for any reason. The review also looked into the effect of caffeine on pregnancy complications. While caffeine was once thought to increase the risk of preterm birth, this is no longer believed to be the case.
- In addition, caffeine intake was looked at in couples who were undergoing medically-assisted conception, such as intrauterine insemination (IUI), intracytoplasmic sperm injection (ICSI), frozen embryo transfer (FET), and fresh in vitro fertilization (IVF).
In a 2019 study published in Fertility and Sterility, more than 1700 couples studied in Denmark, where more women drink coffee in the first place and where caffeine intake is less likely to be stopped prior to medically-assisted conception practices.
Coffee and caffeine consumption were found to be completely unrelated to the chances of getting pregnant or having a healthy live birth after IVF cycles.
This study supported other studies that showed no difference in caffeine consumption and overall fertility in couples who were trying to get pregnant naturally.
- Caffeine did not affect the semen quality or quantity either. One study even showed a greater chance of a successful IUI treatment in those who drank a lot of coffee compared to those who didn’t drink coffee at all.
- Coffee and caffeine have also been linked to improving ovulation chances and a decreased risk of infertility because of anovulation (lack of ovulation) in healthy women.
Can you have a cup of coffee? The Conclusion…
Moderation is the key if you must have a cup of coffee or maybe two*, but do try to limit your caffeine intake to coffee and tea only (no soda or energy drinks at all)!
According to the Mayo Clinic, “Up to 400 milligrams (mg) of caffeine a day appears to be safe for most healthy adults. That’s roughly the amount of caffeine in four cups of brewed coffee**… Even among adults, heavy caffeine use can cause unpleasant side effects. And caffeine may not be a good choice for people who are highly sensitive to its effects or who take certain medications. Women who are pregnant or who are trying to become pregnant and those who are breastfeeding should talk with their doctors about limiting caffeine use.”
Knowing that however, for some caffeine can affect hormonal balance, interfere with or prevent ovulation, and increase chances of a miscarriage. Herbalist and Nutritionist Hethir Rodriguez shares, “One influential 2008 study by the Kaiser Permanente Division of Research found that women who consumed more than 200 milligrams of caffeine – about two cups of coffee or five cans of soda – or more a day in pregnancy actually increased their risk of miscarriage (compared to women who did not consume caffeine during their pregnancy).” So I don’t suggest drinking caffeine in pregnancy.
While there will certainly be more research on the subject of caffeine and fertility in the future, there is no evidence to date that indicates caffeine consumption while trying to conceive is bad for you. In fact, for women having IUI, it might actually be beneficial. If you already drink coffee and are trying to get pregnant, nothing says you can’t continue this. Until more research is done on IUI and caffeine consumption, however, you probably don’t need to start drinking coffee in order to be successful in getting pregnant.
*On average an 8-oz brewed cup of coffee contains 95 mg; one 1–1.75 oz espresso shot contains 63 mg, and an 8-oz brewed cup of decaffeinated coffee contains 3 mg of caffeine (all approximations).
**Espresso drinks are often filled with sugar, high in fat and calories. These are best avoided!
- Chavarro, J.E. (July 2019). Is coffee bad for reproduction? Maybe not, after all. Fertility and Sterility. Volume 112, Issue 1, Pages 39–40. Retrieved from https://www.fertstert.org/article/S0015-0282(19)30412-1/fulltext
- SchiølerKesmodelPh.D.c, U., Hans JakobIngerslevD.M.Sc.be, e, & HøstRamlau-HansenPh, C. (2019, April 28). Impact of female daily coffee consumption on successful fertility treatment: a Danish cohort study. Fertility and Sterility. Volume 112, Issue 1, Pages 120-129.e2. Retrieved from https://www.sciencedirect.com/science/article/pii/S0015028219302870
- E.ChavarroM.D., J., & J.GaskinsSc.D.bd, A. (2018, September 7). Caffeine, alcohol, smoking, and reproductive outcomes among couples undergoing assisted reproductive technology treatments. Fertility and Sterility. Volume 110, Issue 4, Pages 587-592. Retrieved from https://www.sciencedirect.com/science/article/pii/S0015028218304278
- Mayo Clinic Staff (n.d.). Caffeine: How much is too much? Retrieved from https://www.mayoclinic.org/healthy-lifestyle/nutrition-and-healthy-eating/in-depth/caffeine/art-20045678
- Rodriguez, H. (Updated December 6th, 2018). The Natural Fertility Diet: How to Eat for Optimal Fertility. Retrieved from https://natural-fertility-info.com/fertility-diet
Dr. Traxler is a University-trained obstetrician/gynecologist, working with patients in Minnesota for over 20 years. She is a professional medical writer; having authored multiple books on pregnancy and childbirth; textbooks and coursework for medical students and other healthcare providers; and has written over 1000 articles on medical, health, and wellness topics. Dr. Traxler attended the University of Minnesota College of Biological Sciences and University of Minnesota Medical School, earning a degree in biochemistry with summa cum laude honors in 1981, and receiving her Medical Doctorate degree (MD) in 1986.
