A woman's hormones differ from a man's, and so she doesn't react to caffeine the same way a man does. If you're a woman, it doesn't appear that you have to worry about drinking a cup of coffee in the morning. But the caffeine can affect you, and more research is needed. You may want to talk with your doctor about your consumption. This is especially true if you are pregnant.
Fibrocystic Breast Syndrome
Fibrocystic breast syndrome is a common medical condition that women of childbearing age often experience. Hormonal fluctuations cause noncancerous lumps in the breast to fill with fluids, which induces swelling and tenderness just before and during menstruation. The American Pregnancy Association advised that caffeine may exacerbate swelling. And research during the 1980s and 1990s found a correlation between caffeine and fibrocystic breast syndrome. More recent research, however, indicates no link between caffeine consumption and fibrocystic breast syndrome.
Bone Density
A study published in the October 1994 edition of "The American Journal of Clinical Nutrition" concluded that post-menopausal women with a calcium intake below the dietary allowance of 800 mg experienced accelerated bone loss, in comparison with those with a higher intake of calcium. Although the study didn't find that caffeine by itself causes bone loss, it did find that caffeine and calcium taken together can cause bone loss.
Hormonal Imbalance
Dr. Marcelle Pick, an obstetrician-gynecologist and founder of Women to Women, a clinic that offers a combination of alternative and conventional health-care services, says that excessive amounts of caffeine may cause adrenal imbalance that results in sleep disturbances. Stress on the adrenal glands may also affect hormonal levels as women transition into menopause. A study published in a 2002 edition of "Psychomatic Medicine" found that caffeine elevates the stress hormones, corisol, norepinephrine and epinephrine. Increased levels of stress hormones heighten blood pressure and heart rate and reduce the supply of oxygen to the brain, which suppresses the immune system. Women may be more sensitive to these effects than men.
Pregnancy
Studies regarding the effect of caffeine consumption during pregnancy are conflicting. A two-year study from 1996 to 1998 led by Dr. De-Kun Li of Kaiser Permanente found that pregnant women who drank two or more cups of coffee daily doubled their risk of miscarriage, in comparison to women who didn't drink coffee. But another study published in the October 2010 edition of "Food and Chemical Toxicology" found no relation between caffeine and pregnancy outcome. If you're pregnant, ask your doctor if you should cut back on your coffee consumption or avoid it entirely.
References
- Duke University: Studies of Caffeine and Coffee Drinking
- "Food and Chemical Toxicology"; Epidemiologic Evidence Concerning Reproductive Health Effects of Caffeine Consumption; Peck J.D., et al.; October 2010
- PubMed Health: Fibrocystic Breast Disease
- Women to Women; Caffeine and Adrenal Health; Marcelle Pick, OB/GYN, N.P.
- "The American Journal of Clincal Nutrition"; Caffeine and Bone Loss in Healthy Postmenopausal Women; SS Harris, et al.; October 1994
- "Journal of the American College of Nutrition"; Bone Status Among Postmenopausal Women with Different Habitual Caffeine Intakes; Tom Lloyd, Ph.D., et al.; April 2000
