By Michael E. Newman, Pure Matters
Most Americans older than 60 love their coffee. The National Coffee Association says older adults drink the most coffee.
Is that good or bad for you? A slew of studies in the last 40 years have addressed coffee's impact on older Americans -- especially the effects of caffeine. All in all, the news is good. It seems modest consumption yields few, if any, health risks. What's modest? No more than three 8-ounce cups a day of caffeinated coffee, or about 250 mg of caffeine.
A stimulant, caffeine revs up the nervous system minutes after you drink it. Positive effects include better reaction time, mental acuity, alertness, and mood, as well as pain relief. But caffeine may also cause nervous jitters, trouble sleeping, stomach upset, and heartburn.
Here's what the research says about some common health concerns.
High blood pressure
Caffeinated drinks, including coffee, raise your blood pressure slightly by increasing the levels of stress hormones.
"However, long-term evaluations of moderate coffee drinkers -- including studies focusing on seniors -- found that this effect drops off after a while because most people develop a tolerance to caffeine," says Linda Massey, Ph.D., R.D., an expert on senior nutrition in Spokane, Wash. "The studies indicate that coffee drinkers are not at higher risk for developing chronic hypertension."
Part of the Brigham and Women's Hospital and Harvard Medical School-based Nurses Health Study looked for links between coffee and coronary heart disease (CHD). Researchers studied nearly 86,000 women from 1980 to 1990. They found that even women who drank six or more cups of coffee a day did not show an increased risk for heart disease. A similar study in 1990 of 45,000 men ages 45 to 70 by the Harvard School of Public Health also showed that drinking four or more cups of coffee a day did not increase the risk for a heart attack.
Two substances in caffeinated coffee -- kahweol and cafestol -- could raise your cholesterol levels. The American Heart Association says, however, that paper filters take out these substances. That means you needn't worry if you drink filtered coffee. But that isn't true if you enjoy cappuccinos, lattes, and other unfiltered, espresso-based drinks. These drinks also tend to be high in fat because of the whole milk and whipped cream used.
A 2006 study in the American Journal of Epidemiology found that middle-aged adults who drank four or more cups of coffee a day -- regular or decaf -- had a lower risk of developing type 2 diabetes. The researchers say ingredients in coffee appear to decrease the amount of sugar in your blood.
"Several recent studies suggest that coffee may have anticancer properties," says Robert Shmerling, M.D., a Boston medical researcher. He cited studies showing that coffee drinkers were 25 to 75 percent less likely to get cancer of the colon, liver, and breast.
Dr. Shmerling says antioxidants in coffee reduce cell damage from free radicals. That may explain these effects.
Caffeine makes people urinate more, and that leads to a loss of calcium. Large studies of women after menopause show they are more sensitive to this effect than younger women. But significant calcium loss -- and the risk for osteoporosis that goes with it -- is only likely if a woman isn't getting enough calcium in her diet.
Studies show that people who drink alcohol but also drink three or more cups of coffee a day have half the risk for cirrhosis, compared with people who drink alcohol but not coffee.
One study looked at 30 years of data from the Honolulu Heart Program. It found that men who did not drink coffee were two to three times more likely to develop the disease than those who drank one to four cups of caffeinated coffee a day. The researchers suggest caffeine may block the brain's receptors for a chemical called adenosine. That lets the level of another chemical, dopamine, increase. Dopamine controls the smooth, coordinated function of the body's muscles and movement. Lack of dopamine causes Parkinson's.