Coffee or Tea?
Today, coffee is a much more popular beverage choice among Americans than tea, although green tea is gaining popularity with health-conscious individuals.
Regular tea and coffee contain caffeine, but coffee typically has 2-3 times more than tea. Caffeine consumption has some ill physiological effects but probably has little or no impact on the overall risk of cancer and cardiovascular disease. The negative effects of caffeine include increased anxiety and panic attacks, more trouble falling asleep, increased indigestion and reflux, and headaches.1 For those concerned about the negative effects of caffeine, herb tea and both decaffeinated tea and coffee are available. Caffeine is just one of many chemical substances found in tea and coffee. It is possible that one or more of these other chemicals could impact the risk of serious illness.Coffee and CholesterolSome but not all studies have found an increased cholesterol level and/or an increased risk of coronary heart disease in coffee drinkers. It seems likely that it is not the caffeine in coffee that is responsible for increasing serum cholesterol levels.2 Coffee has been shown to contain two plant chemicals called diterpene compounds (cafestol and kahweol). These compounds have been shown to increase LDL-cholesterol (or ?bad? cholesterol) levels.3Five cups of coffee daily could raise serum cholesterol as much as 5 to 10%. If the coffee is consumed with cream and sugar, this would raise blood lipids even more. In theory, the regular consumption of 5 or more cups of unfiltered coffee daily with cream and sugar could easily increase cardiovascular disease risk factors sufficiently to increase the risk of a heart attack by at least 30 to 50%.What about paper-filtered coffee? Passing coffee through a paper filter appears to remove most of these diterpene compounds, and so filtered coffee appears to have less of a tendency to raise LDL levels than does unfiltered coffee.4 However, a recent study concluded, ?Consumption of filtered coffee, in doses that are commonly consumed, was associated with increased levels of homocysteine and total cholesterol.?5Coffee also appears to contain another yet-to-be-identified substance that raises homocysteine levels. Like increased LDL higher levels of serum homocysteine have been linked to an increased risk of cardiovascular disease, and lowering homocysteine levels is likely to help reduce heart attacks and strokes.6 More recently, elevated homocysteine levels have been associated with perhaps a two-fold increased risk of developingAlzheimer?s disease.7The bottom line on coffeeThe bulk of the scientific research shows that the consumption of unfiltered black coffee raises total and LDL and is probably a significant risk factor for the development of atherosclerosis, heart disease and stroke. While filtered coffee does have less impact on blood lipids than unfiltered coffee, it may still modestly elevate serum cholesterol levels and also increase homocysteine. This means even filtered coffee may increase the risk of cardiovascular disease and possibly Alzheimer?s disease as well.Is tea healthier than coffee?In contrast to coffee, there is growing scientific evidence that regular consumption of tea may reduce the risk of cardiovascular disease and perhaps also help reduce the overall risk for developing cancer.8, 9 Tea (both black and green) contains a variety of beneficial plant chemicals called flavonoids that may reduce the oxidation of LDL particles and/or reduce the tendency of blood platelets to stick to artery walls.10 This suggests that black tea may reduce the risk of clogged arteries and/or heart attacks.11 A Welsh study of 3,454 older subjects found that those who consumed more tea were less likely to have more advanced atherosclerotic lesions in their aortas.12 More recently a 5.6 year longitudinal analysis of data from the Rotterdam Study found a 70% lower risk of a fatal heart attack in those who consumed at least 2-3 cups of black tea daily compared to those who were not tea drinkers. The authors concluded, ?An increased intake of tea and flavonoids may contribute to the primary prevention of ischemic heart disease.?13Tea: The healthier choiceRegular consumption of coffee is likely to increase the risk of cardiovascular disease and may also increase the risk of Alzheimer?s disease. By contrast, choosing black or green tea instead of coffee is likely to reduce the risk of cardiovascular disease and may also reduce the risk of at least some types of cancer. Clearly, tea is the healthier choice.By James J. Kenney, PhD, RD, LD, FACNReferences:1. West J Med 1992;157:544-532. Am J Clin Nutr 1991;54:599-6053. Am J Clin Nutr 1995;61:1277-834. Am J Epidmiol 2001;153:353-625. Am J Clin Nutr 2001;74:302-76. Nutr Rev 1999;57:299-3057. N Engl J Med 2002;346:502-78. Nutr Rev 2000;58:1-109. Am J Clin Nutr 2000;71(suppl):1698S-702S10. FASEB J 1996;10:A79311. Arch Intern Med 1999;159:2170-412. Am J Clin Nutr 1997;65:1489-9413. Am J Clin Nutr 2002;75:880-6Tea FAQ?sWhy should I drink tea?Tea is good for your heart. Research suggests that 4 to 5 cups of coffee per day, particularly with added cream and sugar, may increase the risk for cardiovascular disease from 30-50%. By contrast, a recent study found that drinking 2 or more cups of tea per day reduced the risk of fatal heart attacks by 70%.Tea is good for your bones, too. A recent epidemiological study, published May 13th in the Archives of Internal Medicine (2002;162:1001-6) by C-H Wu, et al, compared tea drinkers with those who don't drink tea. They found that those who drank tea for 10 or more years had the strongest bones. The habit of drinking tea regularly over a long period of time was a very strong predictor of bone mineral density, even after correcting for age, body weight, exercise, smoking and other risk factors. Tea is a good source of fluoride, and also contains phytochemicals that may promote stronger bones.Tea is good for your teeth. It is a great natural source of fluoride and the tannins in tea may suppress the growth of plaque bacteria. Stronger teeth and less plaque are the key to keeping your teeth into old age.Many studies in animals have found that black and green teas contain phytochemicals that seem to help prevent a variety of cancers. More research is needed but epidemiological studies do suggest that it is likely to prove beneficial.Which is better, green or black tea?Green tea or black tea? They are about the same - they both contain about the same amount of flavonoids and caffeine. You'll likely be healthier if you replace drinking any type of coffee with any type of tea. For people who are very sensitive to caffeine, decaffeinated tea may be a good choice. But most regular teas only contain 30-40 mg of caffeine per cup, far less than a cup of coffee, which is around 135 mg per 8-ounce cup.