Harvard Health Discusses the Pros and Cons of Drinking Coffee

By Editor, on February 23rd, 2012

Coffee Provides Some Health Benefits & Some Health Risks, Harvard Authors Explain In a new article entitled “What is it about coffee?” the editors of Harvard Health Publications, discuss some of the known benefits and drawbacks of drinking coffee.

The new article on coffee is found in Harvard Healthbeat, a blog and e-newsletter published by Harvard Health Publications of Harvard Medical School.

According to the Harvard Health authors, “In excess, coffee, and more particularly, caffeine, can cause problems. But the fretting about two or three cups a day, or even more, is fading as study results suggestive of health benefits from coffee keep on coming in.”

“Coffee drinking is associated with a lower risk of depression among women, a lower risk of lethal prostate cancer among men, and a lower risk of stroke among men and women,” the Harvard authors state. “Earlier research also shows possible (it’s not a done deal) protective effects against everything from Parkinson’s disease to diabetes to some types of cancer.”

How Much Caffeine is in Coffee?

“Coffee consumption accounts for about 75% of the adult intake of caffeine in the United States,” according to the authors. They report that an average 8-ounce cup of coffee contains about 100 milligrams (mg) of caffeine. Tea, they say, has about half as much caffeine as coffee. Decaffeinated coffee has only about 2 to 4 mg of caffeine in an 8-ounce cup.

The Harvard authors state that 10 grams of caffeine, equivalent to the amount contained in 100 cups of coffee, would be a lethal dose.

“The amount [of caffeine] circulating in the blood peaks 30 to 45 minutes after it’s ingested and only small amounts are around eight to 10 hours later. In between, the amount circulating declines as caffeine gets metabolized in the liver,” the authors explain.

Effects of Caffeine

The Harvard authors explain how caffeine is believed to produce beneficial effects in the brain and other parts of the body:

“Caffeine probably has multiple targets in the brain, but the main one seems to be adenosine receptors. Adenosine is a brain chemical that dampens brain activity. By hogging adenosine’s receptors, caffeine sets off a chain of events that affects the activity of dopamine, another important brain chemical, and the areas of the brain involved in arousal, pleasure, and thinking. A part of the brain affected by Parkinson’s disease, called the striatum, has many adenosine receptors; by docking on them, caffeine seems to have some protective effects.

Outside the brain, caffeine can be a performance enhancer, boosting the strength of muscle contraction and offsetting some of the physiological and psychological effects of physical exertion.”

However, the authors also mention negative effects on the body produced by caffeine, “which include raising blood pressure, making arteries stiffer, and increasing levels of homocysteine, insulin, and possibly cholesterol.”

What is in Caffeine and How Do These Substances Work?

Coffee is believed to contain chlorogenic acid and other antioxidant substances, which the authors indicate may be responsible for the association that has been found between drinking coffee and lower rates of heart disease and diabetes.

The Harvard authors explain that, “Antioxidants are substances that sop up reactive molecules before they have a chance to harm sensitive tissue like the lining of blood vessels. Some experiments have shown that chlorogenic acid may also inhibit absorption of glucose in the digestive system and even out insulin levels.”

At the same time, however, other studies have found that chlorogenic acid “seems to push up levels of homocysteine, an amino acid that has been associated with artery-clogging atherosclerosis.”

“Caffeine and some of these other substances in coffee seem to have their good and bad sides, and coffee’s overall effect may depend on how much they cancel each other out,” the Harvard authors explain.

Coffee may also contain relatively miniscule amounts of magnesium and potassium, minerals that are needed in the diet.

Conclusion

The Harvard authors observe that “It is one thing to say that coffee may be good for you; it’s another to say it’s so good for you that drinking it should be recommended. And we’re not there yet.”

However, the authors do ease concerns of coffee drinkers, concluding that “All of the favorable studies and all of the seemingly healthful ingredients in coffee are good news for coffee drinkers. They can relax and enjoy their habit.”

More Information

See related HelpingYouCare™ reports on:

Swedish Study Suggests Drinking Coffee Associated with Lower Stroke Risk

Eleven Tips for Healthy Sleep (see Tip # 8).

See also the HelpingYouCare™ resource pages on Wellness/ Healthy Living for Seniors & Caregivers, including: