Water is the most consumed beverage on the planet followed by tea. Beer and coffee are next. The health benefits of water, the source of life, need no discussion. The effects of beer for better or worse have been extensively studied and personally examined by this author. Beer however, is not my issue today. That leaves us tea and coffee. There are ample studies examining the health benefits of drinking tea and coffee. Here are some findings:
A study conducted at the National Institutes of Health from 1995 to 2008 involving more than 400,000 people ranging in ages from 50-71 found that people who drank three or more cups of coffee a day had a 10% chance of living longer than those not drinking coffee. Coffee protected against various forms of death with the exception of cancer. Researchers in Japan conducted a study of 40,000 people ages 40-79. They followed people over 11 years and found that those who consumed five or more cups of green tea a day were 16 percent less likely to die from anything during that time compared to people who drink one cup a day. Here is one reason green tea may be beneficial in keeping you alive. Egyptian scientists proposed that drinking green tea, a common practice in their country, is a real asset in treating antibiotic resistant superbugs.
Keep Your Wits about You
In a study conducted at the University of Southern Florida, adults over 65 years of age who drank three cups of coffee daily had lower instances of dementia and Alzheimer’s disease. Participants in the study were already suffering from slight memory impairment. Of the coffee drinkers followed over the course of four years, not one developed Alzheimer’s. For those studied who did develop dementia, their blood caffeine levels were 51 percent lower than those whose mental impairment remained level. Researchers found that older adults in Japan who drank green tea daily showed less risk of memory difficulty, compared with those who didn’t drink tea regularly. An antioxidant found in green tea may protect the brain and fight the memory-robbing effects seen with plaque deposits in Alzheimer’s Disease. This was the conclusion of a study using mice genetically altered to mimic human Alzheimer’s disease, published in the Journal of Neuroscience. This same antioxidant has been linked to a variety of health benefits seen in diets rich in fruits and vegetables, such as protecting against cancer or reducing the risk of heart disease.
While there’s still much to learn about tea’s health benefits, the potential benefits seem to be in the cup, not in supplements or tea extract capsules. So far, there’s no certainty that the compounds in supplements are the same ones in tea, and even less certainty that these supplements might provide the same potential health benefits as tea.
Must be More Than the Caffeine
In another study using mice conducted at Mount Sinai School of Medicine, decaffeinated coffee helped to ward off, and possibly treat, mental decline. The findings from that study also demonstrated that the brain metabolizes glucose better when drinking decaffeinated coffee on a regular basis. This was also good news for sufferers of the increasingly common Type-2 Diabetes. More recently, Australian researchers looked at 18 studies of nearly 458,000 people. They found a 7% drop in the odds of having Type-2 Diabetes for every additional cup of coffee drunk daily. There were similar risk reductions for decaf coffee drinkers and tea drinkers.
Recent studies have found that green tea is good for the skin and may even contribute to a longer life. Green tea contains polyphenols. Black tea does as well, but green tea usually contains more. These are anti-oxidants that reduce inflammation and fight off infection. There may be other things as yet unknown inside tea that could contribute to this benefit.
Jiali Han, PhD, an associate professor at Harvard conducted a study with her colleagues and found coffee decreases the risk of developing the most common form of skin cancer, basal cell carcinoma. In fact, the more cups of coffee that you drink, the greater that the benefit seemed to be. They studied 112,897 people, 22,786 of whom developed basal cell carcinoma. But as coffee consumption increased, the less likely they were to develop the cancer.
In a study of approximately 130,000 Kaiser Permanente Health Plan members, people who reported drinking one to three cups of coffee per day were 20% less likely to be hospitalized for abnormal heart rhythms (arrhythmias) than nondrinkers, regardless of other risk factors. Investigators at Cleveland Clinic’s Wellness Institute and Harvard University found that drinking coffee, including decaffeinated coffee, can decrease the risk of strokes. This is thought to be due to coffee’s beneficial, rich antioxidant content rather than caffeine. When compared against soda, which elevated the risk of strokes, coffee was associated with a 10% decrease in stroke risk. Then there’s the potential effect on lowering Type-2 Diabetes risk. Type-2 Diabetes makes heart disease and stroke more likely. Kknown for its antioxidants, immune boosting and, antihypertensive effects, black tea may also be used to control diabetes, according to a study in the Journal of Food Science.
Evidence for the beneficial effect of green tea on risk factors for heart disease has emerged. Research has found that the consumption of green tea rapidly improves the function of (endothelial) cells lining the circulatory system; endothelial dysfunction is a key event in the progression of atherosclerosis. Tea consumption has been associated with reduced cardiovascular morbidity and mortality in several studies. Green tea is consumed less in the Western World than black tea, but it could be more beneficial because of the way it seems to improve endothelial function. In this same context, recent studies have also shown potent anti-carcinogenic effects of green tea, attributed to its antioxidant properties.
Various studies have concluded that higher consumption of coffee is associated with decreased risk of Parkinson’s. For those already affected, a study headed by Dr. Ronald Postuma from McGill University, found that caffeine helped to boost movement control and muscle stiffness. Patients were given caffeine in pills that were equal to two to four cups of coffee consumed daily. The effect was considered moderate but coffee is so accessible that it was recommended as part of therapy.
Scientists have confirmed that the healthful antioxidant substances found in green tea are absorbed into tissues of the eye. These reports documented that the lens, retina, and other eye tissues incorporate these substances. The authors then proposed green tea may protect against glaucoma and other common eye diseases.
White tea has demonstrated anti-obesity effects. In a series of experiments researchers have shown that white tea extract mobilizes stored fat and inhibits formation of new fat cells. In a study using mice published in the American Journal of Physiology, green tea extract boosted exercise endurance 8-24%, utilizing fat as an energy source. The tea consumption equivalence for humans was placed at four cups daily for over 10 weeks.
All That Glitters …
So while it seems by the above that coffee and tea could make us into a world of super humans, we all know about too much of a good thing. Pregnant women who drink many cups of coffee daily may be at greater risk for miscarriage than non-drinkers or moderate drinkers. Drink a lot of coffee and you may head to the bathroom more often. Caffeine makes you urinate more than you would without it. Decaffeinated coffee has about the same effect on urine production as water. Both regular and decaffeinated coffee contain acids that can make heartburn worse. Heavy caffeine use, four to seven cups of coffee a day, can raise blood cholesterol levels and cause problems such as restlessness, anxiety, irritability, and sleeplessness, particularly in susceptible individuals.
Tea leaves may contain substances that in high levels cause harm. Fluoride, aluminum, caffeine, and oxalates, all found in teas, may lead to problems if over the top amounts are consumed.
In a highly criticized 2012 study, men who drank large quantities of black tea consisting of more than seven cups per day increased their risk of prostate cancer by 50%. Those drinking fewer than seven cups a day showed no increased risk.
All in all there is agreement. Significant benefits may be derived from the consumption of coffee and tea. So drink responsibly, reap the benefits, and enjoy.
You may enjoy the finest coffees and teas at the Pawling Trading Company in the Village of Pawling. Up and running in April 2013, make sure to check out our new on-line store at PawlingTradingCo.com.
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- The study, “Green tea extract improves endurance capacity and increases muscle lipid oxidation in mice,” was conducted by Takatoshi Murase, Satoshi Haramizu, Akira Shimotoyodome, Azumi Nagasawa and Ichiro Tokimitsu, appears in the online edition of the American Journal of Physiology-Regulatory, Integrative and Comparative Physiology, published by the American Physiological Society.
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