With coffee, more may be better for realizing health benefits

Eric Zelz | BDN
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By Georgia Clark-Albert, Special to the BDN
Posted Nov. 28, 2011, at 1:38 p.m.

Are you drinking a cup of coffee as you read the morning paper? Keep right on drinking. Coffee won’t stunt your growth. Besides providing a source of caffeine, coffee contains a host of bioactive components such as polyphenol chlorgenic acid, an antioxidant, and minerals. Antioxidants are what protect us from toxic free radicals. Antioxidants help stave off heart disease, cancer, stroke and diabetes.

It’s comforting to think that our morning pick-me-up may also provide a range of health benefits. While early evidence suggested that drinking coffee might be linked to increased risk of cardiovascular disease, type 2 diabetes and more, current findings suggest potential benefits.

Type 2 diabetes

Evidence consistently links coffee consumption with decreased risk of type 2 diabetes. A linear dose-response relationship between increased coffee consumption and reduced risk of type 2 diabetes exists as follows:

• Drinking 3-4 cups daily: 20 percent reduced risk.

• Drinking 5-6 cups daily: 30 percent reduced risk.

• Drinking 6-plus cups daily reduced risk by 40 percent.

Whether reduced glucose uptake is related to the presence of caffeine or to other bioactive components such as CGAs has not yet been determined.

Heart disease

A modest protective benefit and a 16 percent reduced relative risk of coronary heart disease has been shown among women consuming 2-3 cups of coffee daily. Relative risk of CHD reduces to 28 percent for men and 13 percent women drinking 6 cups of coffee or more daily compared to nondrinkers of coffee. Other studies suggest there may be a lower risk of cardiovascular disease mortality among both men and women by as much as 10-15 percent with the consumption of 3-4 cups of coffee per day.

Endometrial cancer

Long-term coffee consumption may also be associated with a reduced risk for endometrial cancer. Edward Giovannucci, MD, professor of nutrition and epidemiology at the Harvard School of Public Health, said coffee is emerging as a protective agent in cancers that are linked to obesity, estrogen and insulin. Giovannucci observed cumulative coffee intake in relation to endometrial cancer in 67,470 women who enrolled in the Nurses’ Health Study. During the course of 26 years of follow-up, researchers documented 672 cases of endometrial cancer. Drinking more than four cups of coffee per day was linked with a 25 percent reduced risk for endometrial cancer. Drinking between two and three cups per day was linked with a 7 percent reduced risk. A similar link was seen in decaffeinated coffee, where drinking more than two cups per day was linked with a 22 percent reduced risk for endometrial cancer.

Alzheimer’s disease

Several studies suggest that a daily caffeine habit may be protective against Alzheimer’s disease. However, the cup or two a day that many Americans drink doesn’t seem to be enough. Researchers say that about 500 milligrams of caffeine is the dose that seems to protect the brain. A cup (8 ounces) of brewed coffee contains anywhere from 95-200 milligrams of caffeine.

One recent study comes from Finland, where researchers followed about 1,400 coffee drinkers for two decades. The group that seemed to benefit the most was the people who’d been drinking three to five cups of coffee a day in their 40s and 50s. They had about a 65 to 70 percent reduced risk of developing Alzheimer’s diseases in their 70s.

Researcher Reisa Sperling hesitates to say that there’s epidemiological evidence that coffee prevents Alzheimer’s disease.

“It’s possible that these regular coffee drinkers might have other habits in common that could explain the protective effect,” Sperling said. “People who are very active in mid-life are more likely to be drinking coffee than couch potatoes, so the coffee drinkers may be benefiting more from keeping their minds and bodies active.” Sperling says Alzheimer’s is an incredibly complicated disease. Exercise and good nutrition do seem to be protective, but a person’s risk is largely determined by genes. No one behavior or diet change, such as coffee drinking, can erase that risk.

Research findings that link coffee consumption (from 3 to 10 cups daily) to heart and diabetes health benefits, as well as protection from age-related brain decline, continue to emerge. Exactly which components in coffee are responsible for conferring these long-term health benefits is still under investigation. So don’t feel guilty when you go for that second or third cup of coffee in the morning or later in the day.

Georgia Clark-Albert is a registered dietitian and adjunct nutrition instructor at Eastern Maine Community College who lives in Athens. Read more of her columns and post questions at bangordailynews.com or email her at GeorgiaMaineMSRDCDE@gmail.com.

http://bangordailynews.com/2011/11/28/health/with-coffee-more-may-be-better-for-realizing-health-benefits/ printed on July 22, 2014