IF that shot of espresso revs you up even though you ordered decaf, don't accuse the server of giving you the real thing. A Swiss study has found that occasional coffee drinkers get a buzz from decaf – their systolic blood pressure (the first number) goes up and their nervous system is stimulated.
One of the other components of coffee, not the caffeine, is the likely cause, conclude University of Zurich researchers. Regular coffee drinkers don't get the same lift in blood pressure even after drinking the real thing, probably because they've developed a tolerance.
The blood pressure, heart rate and nervous system activity of six coffee drinkers and nine people who drank the brew from time to time were measured before, during and after drinking a triple espresso and a decaf triple espresso, and before, during and after receiving intravenous caffeine and an intravenous placebo of saline.
The systolic blood pressure of those who don't usually drink coffee jumped an average 12 millimeters of mercury an hour after drinking the triple espresso and after the decaf. The blood pressure of those with a coffee habit barely budged.
“Those with heart rhythm disturbances, high blood pressure or both, and those who have been told to avoid coffee and caffeine-containing beverages should continue to do so,” says Dr David A. Meyerson, a cardiologist and a spokesman for the American Heart Association. The research appeared in the Nov 19 online version of Circulation.
Unanswered questions about fibre and cancer
ALTHOUGH fibre is believed to protect against colorectal cancer, the effect has never been proved – and new research has failed to resolve the issue.
University of Arizona researchers took a second look at data from a study several years ago showing that high-fibre supplements didn't prevent the recurrence of polyps, benign tumours that can become malignant. But that study didn't answer questions about how much fibre the participants were consuming in food. So the researchers analysed information about fibre-rich foods from participants' dietary questionnaires. They found that fibre from fruits, vegetables and grains had no effect on polyp recurrence.
But don't forgo your bran cereal just yet.
Arthur Schatzkin, chief of the Nutritional Epidemiology Branch of the National Cancer Institute, points out that fibre may not prevent the polyp from forming, but it might prevent it from becoming malignant.
The research was published in the Nov. 6 issue of the Journal of the National Cancer Institute.
Depression may raise risk of premature births
ONE in five women suffers from depression, and the first bout with the blues often occurs during pregnancy. But little is known about how depression affects pregnancy. Now a study has found that it significantly increases the chances of premature delivery in African American women, who have about double the rate of pre-term births as white women.
Researchers followed more than 1,000 African American women who were evaluated for depression at four Baltimore clinics that serve low-income areas. Nearly 13% of the women who had high scores on the depression scale gave birth prematurely, compared with 8% of those who had low scores.
When the researchers took into account the effects of known risks such as low weight gain during pregnancy or drug use, the depressed women were nearly twice as likely to have a spontaneous pre-term birth as those who weren't depressed.
Treating the mood disorder with therapy and antidepressants that can be safely taken during pregnancy may help reduce the risk of pre-term birth, says Suezanne T. Orr, lead author of the study and associate professor of health education at East Carolina University in Greenville. The report was published in the November issue of the American Journal of Epidemiology.
Abdominal fat could be linked to bone density
MUCH of what is known about bone loss comes from studies comparing sedentary people with those participating in vigorous exercise programmes, and obese people compared with normal-weight ones. Until now, little has been known about bone loss in people who do routine physical activities, such as walking, and who are a little overweight.
Researchers at Johns Hopkins University in Baltimore, studied healthy men and women older than 55 who fit this description to find out what helped them retain bone and what didn't. Their finding was published in the November issue of the Journal of Internal Medicine. Of all the factors studied, carrying a little weight around one's midsection was associated with less bone loss.
The unexpected finding shouldn't prompt people to give up on losing weight, caution the researchers. There are too many other health risks, such as cardiovascular disease and diabetes, that are associated with abdominal fat.
The relationship between fat and bone deserves further study, the researchers say. – LAT-WP