Your daily dose of caffeine might tinker with more than just your energy levels.
A new study of women ages 18 to 44 found that drinking coffee and other caffeinated beverages can briefly alter levels of estrogen. But the effect varies by race. In white women, for example, coffee appears to lower estrogen, while in Asian women it has the reverse effect, raising levels of the hormone.
The study, which was published in the American Journal of Clinical Nutrition, did not look at older women. But women of childbearing age who enjoy a daily cup of coffee have little reason to fret, the researchers said. The effects of caffeine on estrogen are so minimal that in healthy women, it has no effect on ovulation or overall health, at least in the short term.
“This is important, physiologically, because it helps us understand how caffeine is metabolized by different genetic groups,” said Enrique Schisterman, an author of the study and a senior investigator at the National Institutes of Health. “But for women of reproductive age, drinking coffee will not alter their hormonal function in a clinically significant way.”
He noted that more research was needed. “We don’t know if there are long-term effects of these small shifts in hormonal levels,” he said.
Oral HPV affects 7 percent of Americans
About one in 15 Americans is infected with oral human papillomavirus, or HPV, a sexually transmitted virus that causes throat cancer, new research shows.
Oral HPV has drawn growing attention from public health experts because it has fueled a rise in oropharyngeal cancer, which affects the back of the tongue and the throat. Genital HPV is far more common and can lead to cervical, anal, and other cancer.
The report, published in the Journal of the American Medical Association, looked at nearly 6,000 people across the country and found that 6.9 percent of adults and teenagers are infected with oral HPV of any kind. The virus was about three times as common in men as it was in women.
The scientists identified several factors that significantly raised the risk of becoming infected: increasing age, greater sexual activity, and cigarette smoking.
But Dr. Maura L. Gillison, the chairwoman of cancer research at Ohio State University and the senior author of the paper, offered some reassurance. Only about 1 percent of Americans, or about 2 million people overall, are thought to be infected orally with HPV Type 16, the strain linked to throat cancer. Fewer than 10,000 cases of throat cancer caused by HPV 16 are diagnosed every year, indicating that most people with the virus do not develop cancer.
Taking BP on both arms urged
Doctors who make a habit of measuring blood pressure in only one arm might be doing their patients a disservice.
A new study shows that differences in blood pressure readings between a patient’s right and left arms could be a sign of vascular disease and a greater risk of dying from heart disease.
The study, published in the Lancet, suggests doctors should always take blood pressure readings on both arms.
“Recommendations to measure both arms exist in both British and American blood pressure management guidelines,” said Dr. Christopher Clark, the lead author of the study and a clinical academic fellow at the Peninsula College of Medicine and Dentistry in England. “But it’s guidance that isn’t regularly followed.”
The consequences could be significant. A difference of 15 millimeters of mercury or more in the systolic pressure, the top number in a reading, was associated with a 70 percent greater risk of dying from heart disease.
The precise number of the higher or lower systolic reading was less important than the extent of the difference. A difference of even 10 millimeters was enough to raise the risk of peripheral vascular disease.
The authors hypothesized that different blood pressure readings in the two arms were a sign of the narrowing or hardening of a person’s arteries, particularly on one side of the body.