What is it?
Black tea is a product made from the Camellia sinesis plant. The aged leaves and stems are used to make medicine. Green tea, which is made from fresh leaves of the same plant, has some different properties.
Black tea is used for improving mental alertness as well as learning, memory and information processing skills. It is also used for treating headache and low blood pressure; preventing heart disease, including “hardening of the arteries” (atherosclerosis) and heart attack; preventing Parkinson's disease; and reducing the risk of stomach and colon cancer, lung cancer, ovarian cancer, and breast cancer. It is also used for type 2 diabetes, stomach disorders, vomiting, diarrhea, and as a diuretic to increase urine flow. Some people use black tea for preventing tooth decay and kidney stones. In combination with various other products, black tea is used for weight loss.
In foods, black tea is consumed as a hot or cold beverage.
How effective is it?
Natural Medicines Comprehensive Database rates effectiveness based on scientific evidence according to the following scale: Effective, Likely Effective, Possibly Effective, Possibly Ineffective, Likely Ineffective, Ineffective, and Insufficient Evidence to Rate.
The effectiveness ratings for BLACK TEA are as follows:
Likely effective for...
- Mental alertness. Drinking black tea and other caffeinated beverages throughout the day helps to keep people alert, even after extended periods without sleep.
Possibly effective for...
- Preventing dizziness upon standing up (orthostatic hypotension) in older people. Black tea works for this condition because it raises blood pressure.
- Reducing the risk of heart attacks. There is some evidence that people who drink black tea have a lower risk of heart attack. If they do have a heart attack, they are less likely to die if they have been drinking black tea for at least a year.
- Reducing the risk of kidney stones. Women who drink black tea seem to have an 8% lower risk of developing kidney stones.
- Reducing the risk of Parkinson's disease. There is some evidence from large-scale studies that people who drink caffeinated beverages such as coffee, tea, and cola have a decreased risk of Parkinson's disease. For men, the effects seem to be dose-related. For example, men consuming a total of 421-2716 mg of caffeine daily seem to have the greatest reduction in risk. However, there seems to be a significant reduction in risk even with consumption of as little as 124-208 mg caffeine per day. In women, the effects do not seem to be dose- related. Moderate consumption of caffeine (about one to four cups black tea daily) seems to provide the most reduction in risk. Drinking black tea also appears to reduce the occurrence of Parkinson's disease among people who smoke.
- Reducing the risk of ovarian cancer. Women who regularly drink tea, including black tea or green tea, appear to have a significantly lower risk of developing ovarian cancer compared to women who never or seldom drink tea.
- Reducing the risk of hardening of the arteries (atherosclerosis), especially in women.
Possibly ineffective for...
- Reducing the risk of stomach, colon, and rectal cancer.
- Reducing the risk of breast cancer.
Insufficient evidence to rate effectiveness for...
- Brittle bones (osteoporosis). So far there is some evidence that drinking black tea might be linked to stronger bones in women aged 65-76 years. Drinking black tea also seems to be associated with a lower risk of hip fracture in men and women who are older than 50.
- Type 2 diabetes. Some research suggests that Japanese adults who drink a cup or more of black tea daily do not have a lower risk of developing type 2 diabetes compared to those who drink less than a cup daily.
- Lung cancer. There is evidence that men who get more chemicals called phytoestrogens in their diet have up to a 27% lower risk of developing lung cancer than men who do not get these chemicals. Green tea and black tea contain phytoestrogens.
- Stomach disorders.
- High blood pressure.
- Preventing tooth decay.
- Reducing the risk of other cancers.
- Promoting weight loss.
- Other conditions.
More evidence is needed to rate the effectiveness of black tea for these uses.
Black tea contains 2% to 4% caffeine, which affects thinking and alertness, increases urine output, and may reduce the symptoms of Parkinson's disease. It also contains antioxidants and other substances that might help protect the heart and blood vessels.
Black tea is safe for most adults. Too much black tea, such as more than five cups per day, can cause side effects because of the caffeine. These side effects can range from mild to serious and include headache, nervousness, sleep problems, vomiting, diarrhea, irritability, irregular heartbeat, tremor, heartburn, dizziness, ringing in the ears, convulsions, and confusion.
People who drink black tea or other caffeinated beverages all the time, especially in large amounts, can develop psychological dependence.
Caffeine is PROBABLY SAFE in children in amounts commonly found in foods.
Special precautions & warnings:
Pregnancy and breast-feeding: If you are pregnant or breast-feeding, black tea in small amounts is probably not harmful. Do not drink more than 2 cups a day of black tea. This amount of tea provides about 200 mg of caffeine. Consuming more than this amount during pregnancy has been linked to an increased risk of miscarriage and other negative effects, including symptoms of caffeine withdrawal in newborns and lower birth weight.
If you are breast-feeding, drinking more than 2 cups a day of black tea might cause your baby to become more irritable and have more bowel movements.
Anemia: Drinking black tea may make anemia worse in people with iron deficiency.
Anxiety disorders: The caffeine in black tea might make these conditions worse.
Bleeding disorders: There is some reason to believe that the caffeine in black tea might slow blood clotting, though this hasn’t been shown in people. Use caffeine cautiously if you have a bleeding disorder.
Heart problems: Caffeine in black tea can cause irregular heartbeat in certain people. If you have a heart condition, use caffeine with caution.
Diabetes: The caffeine in black tea might affect blood sugar. Use black tea with caution if you have diabetes.
Diarrhea: Black tea contains caffeine. The caffeine in black tea, especially when taken in large amounts, can worsen diarrhea.
Irritable bowel syndrome (IBS): Black tea contains caffeine. The caffeine in black tea, especially when taken in large amounts, can worsen diarrhea and might worsen symptoms of IBS.
Glaucoma: Drinking caffeinated black tea increases the pressure inside the eye. The increase occurs within 30 minutes and lasts for at least 90 minutes.
Hormone-sensitive condition such as breast cancer, uterine cancer, ovarian cancer, endometriosis, or uterine fibroids: Black tea might act like estrogen. If you have any condition that might be made worse by exposure to estrogen, don’t use black tea.
High blood pressure: The caffeine in black tea might increase blood pressure in people with high blood pressure. However, this doesn't seem to occur in people who drink black tea or other caffeinated products regularly.
Brittle bones (osteoporosis): Drinking caffeinated black tea can increase the amount of calcium that is flushed out in the urine. This might weaken bones. Don’t drink more than 300 mg of caffeine per day (approximately 2-3 cups of black tea). Taking extra calcium may help to make up for calcium losses. Older women who have a genetic condition that affects the way they use vitamin D, should use caffeine with caution.
Be cautious with this combination.
Black tea contains caffeine. The caffeine in black tea might block the affects of adenosine (Adenocard). Adenosine (Adenocard) is often used by doctors to do a test on the heart. This test is called a cardiac stress test. Stop drinking black tea or other caffeine-containing products at least 24 hours before a cardiac stress test.
Antibiotics (Quinolone antibiotics)
The body breaks down caffeine to get rid of it. Some antibiotics might decrease how quickly the body breaks down caffeine. Taking these antibiotics along with black tea can increase the risk of side effects including jitteriness, headache, increased heart rate, and other side effects.
Some antibiotics that decrease how quickly the body breaks down caffeine include ciprofloxacin (Cipro), enoxacin (Penetrex), norfloxacin (Chibroxin, Noroxin), sparfloxacin (Zagam), trovafloxacin (Trovan), and grepafloxacin (Raxar).
Black tea contains caffeine. The body breaks down caffeine to get rid of it. Cimetidine (Tagamet) can decrease how quickly your body breaks down caffeine. Taking cimetidine (Tagamet) along with black tea might increase the chance of caffeine side effects including jitteriness, headache, fast heartbeat, and others.
The body breaks down clozapine (Clozaril) to get rid of it. The caffeine in black tea seems to decrease how quickly the body breaks down clozapine (Clozaril). Taking black tea along with clozapine (Clozaril) can increase the effects and side effects of clozapine (Clozaril).
Black tea contains caffeine. The caffeine in black tea might block the affects of dipyridamole (Persantine). Dipyridamole (Persantine) is often used by doctors to do a test on the heart. This test is called a cardiac stress test. Stop drinking black tea or other caffeine-containing products at least 24 hours before a cardiac stress test.
The body breaks down caffeine to get rid of it. Disulfiram (Antabuse) can decrease how quickly the body gets rid of caffeine. Taking black tea (which contains caffeine) along with disulfiram (Antabuse) might increase the effects and side effects of caffeine including jitteriness, hyperactivity, irritability, and others.
Stimulant drugs speed up the nervous system. Black tea contains caffeine. Caffeine and ephedrine are both stimulant drugs. Taking black tea along with ephedrine might cause too much stimulation and sometimes serious side effects and heart problems. Do not take caffeine containing products and ephedrine at the same time.
The body breaks down the caffeine in black tea to get rid of it. Estrogens can decrease how quickly the body breaks down caffeine. Taking estrogen pills and drinking black tea can cause jitteriness, headache, fast heartbeat, and other side effects. If you take estrogen pills, limit your caffeine intake.
Some estrogen pills include conjugated equine estrogens (Premarin), ethinyl estradiol, estradiol, and others.
The body breaks down the caffeine in black tea to get rid of it. Fluvoxamine (Luvox) can decrease how quickly the body breaks down caffeine. Taking caffeine along with fluvoxamine (Luvox) might cause too much caffeine in the body, and increase the effects and side effects of caffeine.
Your body naturally gets rid of lithium. The caffeine in black tea can increase how quickly your body gets rid of lithium. If you take products that contain caffeine and you take lithium, stop taking caffeine products slowly. Stopping caffeine too quickly can increase the side effects of lithium.
Medications for asthma (Beta-adrenergic agonists)
Black tea contains caffeine. Caffeine can stimulate the heart. Some medications for asthma can also stimulate the heart. Taking caffeine with some medications for asthma might cause too much stimulation and cause heart problems.
Some medications for asthma include albuterol (Proventil, Ventolin, Volmax), metaproterenol (Alupent), terbutaline (Bricanyl, Brethine), and isoproterenol (Isuprel).
Medications for depression (MAOIs)
The caffeine in black tea can stimulate the body. Some medications used for depression can also stimulate the body. Drinking black tea and taking some medications for depression might cause too much stimulation of the body and serious side effects including fast heartbeat, high blood pressure, nervousness, and others.
Some of these medications used for depression include phenelzine (Nardil), tranylcypromine (Parnate), and others.
Medications that slow blood clotting (Anticoagulant / Antiplatelet drugs)
Black tea might slow blood clotting. Taking black tea along with medications that also slow clotting might increase the chances of bruising and bleeding.
Some medications that slow blood clotting include aspirin, clopidogrel (Plavix), diclofenac (Voltaren, Cataflam, others), ibuprofen (Advil, Motrin, others), naproxen (Anaprox, Naprosyn, others), dalteparin (Fragmin), enoxaparin (Lovenox), heparin, warfarin (Coumadin), and others.
The stimulant effects of the caffeine in black tea can block the sleep-producing effects of pentobarbital.
The caffeine in black tea can stimulate the body. Phenylpropanolamine can also stimulate the body. Taking caffeine and phenylpropanolamine together might cause too much stimulation and increase heartbeat, blood pressure, and cause nervousness.
The body breaks down riluzole (Rilutek) to get rid of it. Drinking black tea can decrease how quickly the body breaks down riluzole (Rilutek) and increase the effects and side effects of riluzole.
Stimulant drugs speed up the nervous system. By speeding up the nervous system, stimulant medications can make you feel jittery and speed up your heartbeat. The caffeine in black tea can also speed up the nervous system. Drinking black tea along with stimulant drugs might cause serious problems including increased heart rate and high blood pressure. Avoid taking stimulant drugs along with black tea.
Some stimulant drugs include diethylpropion (Tenuate), epinephrine, phentermine (Ionamin), pseudoephedrine (Sudafed), and many others.
Black tea contains caffeine. Caffeine works similarly to theophylline. Caffeine can also decrease how quickly the body gets rid of theophylline. This might cause increased effects and side effects of theophylline.
Verapamil (Calan, Covera, Isoptin, Verelan)
The body breaks down the caffeine in black tea to get rid of it. Verapamil (Calan, Covera, Isoptin, Verelan) can decrease how quickly the body gets rid of caffeine. Drinking black tea and taking verapamil (Calan, Covera, Isoptin, Verelan) can increase the risk of side effects for caffeine including jitteriness, headache, and an increased heartbeat.
Warfarin (Coumadin) is used to slow blood clotting. Large amounts of black tea might decrease how well warfarin (Coumadin) slows blood clotting. Decreasing how well warfarin (Coumadin) slows blood clotting might increase the risk of clotting. It is unclear why this interaction might occur. Be sure to have your blood checked regularly. The dose of your warfarin (Coumadin) might need to be changed.
Be watchful with this combination.
The body breaks down the caffeine in black tea to get rid of it. Alcohol can decrease how quickly the body breaks down caffeine. Taking black tea along with alcohol might cause too much caffeine in the bloodstream and caffeine side effects including jitteriness, headache, and fast heartbeat.
Birth control pills (Contraceptive drugs)
The body breaks down the caffeine in black tea to get rid of it. Birth control pills can decrease how quickly the body breaks down caffeine. Taking black tea along with birth control pills can cause jitteriness, headache, fast heartbeat, and other side effects.
Some birth control pills include ethinyl estradiol and levonorgestrel (Triphasil), ethinyl estradiol and norethindrone (Ortho-Novum 1/35, Ortho-Novum 7/7/7), and others.
Black tea contains caffeine. The body breaks down caffeine to get rid of it. Fluconazole (Diflucan) might decrease how quickly the body gets rid of caffeine. This could cause caffeine to stay in the body too long and increase the risk of side effects such as nervousness, anxiety, and insomnia.
Medications for depression (Tricyclic antidepressants)
Black tea contains chemicals called tannins. Tannins can bind to many medications and decrease how much medicine the body absorbs. To avoid this interaction, avoid black tea 1 hour before and 2 hours after taking medications for depression called tricyclic antidepressants.
Some medications for depression include amitriptyline (Elavil) or imipramine (Tofranil, Janimine).
Medications for diabetes (Antidiabetes drugs)
Black tea might increase blood sugar. Diabetes medications are used to lower blood sugar. By increasing blood sugar, black tea might decrease the effectiveness of diabetes medications. Monitor your blood sugar closely. The dose of your diabetes medication might need to be changed.
Some medications used for diabetes include glimepiride (Amaryl), glyburide (DiaBeta, Glynase PresTab, Micronase), insulin, pioglitazone (Actos), rosiglitazone (Avandia), chlorpropamide (Diabinese), glipizide (Glucotrol), tolbutamide (Orinase), and others.
Black tea contains caffeine. The body breaks down caffeine to get rid of it. Mexiletine (Mexitil) can decrease how quickly the body breaks down caffeine. Taking Mexiletine (Mexitil) along with black tea might increase the caffeine effects and side effects of black tea.
Black tea contains chemicals called tannins. Tannins can bind to many medications and decrease how much medicine the body absorbs. To avoid this interaction, avoid black tea 1 hour before and 2 hours after taking phenothiazine medications.
Some phenothiazine medications include fluphenazine (Permitil, Prolixin), chlorpromazine (Thorazine), haloperidol (Haldol), prochlorperazine (Compazine), thioridazine (Mellaril), and trifluoperazine (Stelazine).
The body breaks down the caffeine in black tea to get rid of it. Terbinafine (Lamisil) can decrease how quickly the body gets rid of caffeine and increase the risk of side effects including jitteriness, headache, increased heartbeat, and other effects.
Using bitter orange along with other products that contain caffeine, such as black tea, can increase blood pressure and heart rate in otherwise healthy adults with normal blood pressure. This could increase the risk of serious heart problems.
Caffeine-containing herbs and supplements
Black tea contains caffeine. Using it along with other herbs and supplements that contain caffeine might increase the risk of caffeine side effects. Natural products that contain caffeine include coffee, black tea, green tea, oolong tea, guarana, mate, and others.
High caffeine intake from foods and beverages, including black tea, flushes calcium out of the body in the urine.
There is some concern that combining caffeine, an ingredient in black tea, with ephedra and creatine might increase the risk of serious harmful effects. There is a report of stroke in an athlete who consumed 6 grams of creatine monohydrate, 400-600 mg of caffeine, 40-60 mg of ephedra, and a variety of other supplements daily for 6 weeks. Caffeine might also decrease whatever benefit creatine might have on athletic performance.
Ephedra (Ma huang)
Ephedra and black tea are both stimulants. They speed up the central nervous system. Using them together might speed it up too much, increasing the risk of high blood pressure, heart attack, stroke, seizures, and death. Don't take black tea with ephedra or other stimulants.
Herbs and supplements that might slow blood clotting
Black tea might slow blood clotting. Using it along with other herbs and supplements that might also slow blood clotting could increase the risk of bruising and bleeding in some people. Some of these herbs include angelica, clove, danshen, garlic, ginger, ginkgo, Panax ginseng, and others.
Black tea might interfere with the body's ability to absorb iron. This probably isn't a problem for most people, unless they are iron-deficient. If this is the case, drink tea between meals rather than with meals to lessen this interaction.
Black tea contains caffeine. Using herbs and supplements that contain caffeine can speed up the removal of lithium from the body.
Drinking large amounts of black tea can increase the amount of magnesium that is flushed out in the urine.
Black tea might interfere with the body's ability to absorb iron. This probably isn't a problem for most people, unless they are iron-deficient. If this is the case, drink tea between meals rather than with meals to lessen this interaction.
Adding milk to black tea appears to reduce some of the heart health benefits of drinking tea. Milk might bind with the antioxidants in tea and keep them from being absorbed. However, not all research confirms this. More evidence is needed to determine just how important this interaction, if any, might be.
An 8-ounce serving of black tea provides from 40-120 mg of caffeine, the active ingredient.
The following doses have been studied in scientific research:
- For headache or improving mental alertness: a typical dose is up to 250 mg of caffeine (several cups of black tea) per day.
- For reducing the risk of heart attack and kidney stones: a dose of at least one cup per day.
- For preventing "hardening of the arteries" (atherosclerosis), 125-500 mL (1-4 cups) of brewed black tea daily.
- For preventing Parkinson's disease: men drinking 421-2716 mg of total caffeine (approximately 5-33 cups of black tea) daily have the lowest risk of developing Parkinson's disease, when compared to other men. However, men who drink as little as 124-208 mg of caffeine (approximately 1-3 cups of black tea) daily also have a significantly lower chance of developing Parkinson's disease. In women, moderate caffeine intake (1-4 cups of black tea) per day seems to be best.
Black Leaf Tea, Camellia sinensis, Camellia thea, Camellia theifera, Chinese Tea, English Tea, Feuille de Thé Noir, Té Negro, Tea, Thé Anglais, Thé Noir, Thea bohea, Thea sinensis, Thea viridis, Theaflavin, Théaflavine.
To learn more about how this article was written, please see the Natural Medicines Comprehensive Database methodology.methodology (http://www.nlm.nih.gov/medlineplus/druginfo/natural/methodology.html).
To see all references for the Black tea page, please go to http://www.nlm.nih.gov/medlineplus/druginfo/natural/997.html.
- Parker DL, Hoffmann TK, Tucker MA, et al. Interaction between warfarin and black tea. Ann Pharmacother 2009;43:150-1.
- Savitz DA, Chan RL, Herring AH, et al. Caffeine and miscarriage risk. Epidemiology 2008;19:55-62.
- Weng X, Odouli R, Li DK. Maternal caffeine consumption during pregnancy and the risk of miscarriage: a prospective cohort study. Am J Obstet Gynecol 2008;198:279.e1-8.
- Fukuda I, Sakane I, Yabushita Y, et al. Black tea theaflavins suppress dioxin-induced transformation of the aryl hydrocarbon receptor. Biosci Biotechnol Biochem 2005;69:883-90.
- Kundu T, Dey S, Roy M, et al. Induction of apoptosis in human leukemia cells by black tea and its polyphenol theaflavin. Cancer Lett 2005;230:111-21.
- Way TD, Lee HH, Kao MC, Lin JK. Black tea polyphenol theaflavins inhibit aromatase activity and attenuate tamoxifen resistance in HER2/neu-transfected human breast cancer cells through tyrosine kinase suppression. Eur J Cancer 2004;40:2165-74.
- Mizuno H, Cho YY, Zhu F, et al. Theaflavin-3, 3'-digallate induces epidermal growth factor receptor downregulation. Mol Carcinog 2006;45:204-12.
- Chen CN, Lin CP, Huang KK, et al. Inhibition of SARS-CoV 3C-like Protease Activity by Theaflavin-3,3'-digallate (TF3). Evid Based Complement Alternat Med 2005;2:209-15.
- Liu S, Lu H, Zhao Q, et al. Theaflavin derivatives in black tea and catechin derivatives in green tea inhibit HIV-1 entry by targeting gp41. Biochim Biophys Acta 2005;1723:270-81.
- Tu YY, Tang AB, Watanabe N. The theaflavin monomers inhibit the cancer cells growth in vitro. Acta Biochim Biophys Sin (Shanghai) 2004;36:508-12.
Yanagida A, Shoji A, Shibusawa Y, et al. Analytical separation of tea catechins and food-related polyphenols by high-speed counter-current chromatography. J Chromatogr A 2006;1112:195-201.
- Taubert D, Roesen R, Schomig E. Effect of cocoa and tea intake on blood pressure: a meta-analysis. Arch Intern Med 2007;167:626-34.
- Lorenz M, Jochmann N, von Krosigk A, et al. Addition of milk prevents vascular protective effects of tea. Eur Heart J 2007;28:219-23.
- Correa A, Stolley A, Liu Y. Prenatal tea consumption and risks of anencephaly and spina bifida. Ann Epidemiol 2000;10:476-7.
- Kanis J, Johnell O, Gullberg B, et al. Risk factors for hip fracture in men from southern Europe: the MEDOS study. Mediterranean Osteoporosis Study. Osteoporos Int 1999;9:45-54.
- Iso H, Date C, Wakai K, et al; JACC Study Group. The relationship between green tea and total caffeine intake and risk for self-reported type 2 diabetes among Japanese adults. Ann Intern Med 2006;144:554-62.
- Khokhar S, Magnusdottir SG. Total phenol, catechin, and caffeine contents of teas commonly consumed in the United kingdom. J Agric Food Chem 2002;50:565-70.
- Robinson LE, Savani S, Battram DS, et al. Caffeine ingestion before an oral glucose tolerance test impairs blood glucose management in men with type 2 diabetes. J Nutr 2004;134:2528-33.
- Lake CR, Rosenberg DB, Gallant S, et al. Phenylpropanolamine increases plasma caffeine levels. Clin Pharmacol Ther 1990;47:675-85.
- Forrest WH Jr, Bellville JW, Brown BW Jr. The interaction of caffeine with pentobarbital as a nighttime hypnotic. Anesthesiology 1972;36:37-41.
- Raaska K, Raitasuo V, Laitila J, Neuvonen PJ. Effect of caffeine-containing versus decaffeinated coffee on serum clozapine concentrations in hospitalised patients. Basic Clin Pharmacol Toxicol 2004;94:13-8.
- Watson JM, Sherwin RS, Deary IJ, et al. Dissociation of augmented physiological, hormonal and cognitive responses to hypoglycaemia with sustained caffeine use. Clin Sci (Lond) 2003;104:447-54.
- Winkelmayer WC, Stampfer MJ, Willett WC, Curhan GC. Habitual caffeine intake and the risk of hypertension in women. JAMA 2005;294:2330-5.
- Juliano LM, Griffiths RR. A critical review of caffeine withdrawal: empirical validation of symptoms and signs, incidence, severity, and associated features. Psychopharmacology (Berl) 2004;176:1-29.
- Leson CL, McGuigan MA, Bryson SM. Caffeine overdose in an adolescent male. J Toxicol Clin Toxicol 1988;26:407-15.
- Benowitz NL, Osterloh J, Goldschlager N, et al. Massive catecholamine release from caffeine poisoning. JAMA 1982;248:1097-8.
- Scholey AB, Kennedy DO. Cognitive and physiological effects of an "energy drink:" an evaluation of the whole drink and of glucose, caffeine and herbal flavouring fractions. Psychopharmacology (Berl) 2004;176:320-30.
- Haller CA, Benowitz NL, Jacob P 3rd. Hemodynamic effects of ephedra-free weight-loss supplements in humans. Am J Med 2005;118:998-1003.
- Larsson SC, Wolk A. Tea consumption and ovarian cancer risk in a population-based cohort. Arch Intern Med 2005;165:2683-6.
- Schabath MB, Hernandez LM, Wu X, et al. Dietary phytoestrogens and lung cancer risk. JAMA 2005;294:1493-1504.
- Gupta S, Saha B, Giri AK. Comparative antimutagenic and anticlastogenic effects of green tea and black tea: a review. Mutat Res 2002;512:37-65.
- Petrie HJ, Chown SE, Belfie LM, et al. Caffeine ingestion increases the insulin response to an oral-glucose-tolerance test in obese men before and after weight loss. Am J Clin Nutr 2004;80:22-8.
- Lane JD, Barkauskas CE, Surwit RS, Feinglos MN. Caffeine impairs glucose metabolism in type 2 diabetes. Diabetes Care 2004;27:2047-8.
- Vinson JA, Teufel K, Wu N. Green and black teas inhibit atherosclerosis by lipid, antioxidant, and fibrinolytic mechanisms. J Agric Food Chem 2004;52:3661-5.
- Bischoff HA, Stahelin HB, Dick W, et al. Effects of vitamin D and calcium supplementation on falls: a randomized controlled trial. J Bone Miner Res 2003;18:343-51.
- Sato J, Nakata H, Owada E, et al. Influence of usual intake of dietary caffeine on single-dose kinetics of theophylline in healthy human subjects. Eur J Clin Pharmacol 1993;44:295-8.
- Cannon ME, Cooke CT, McCarthy JS. Caffeine-induced cardiac arrhythmia: an unrecognised danger of healthfood products. Med J Aust 2001;174:520-1.
- Durrant KL. Known and hidden sources of caffeine in drug, food, and natural products. J Am Pharm Assoc 2002;42:625-37.
- Beach CA, Mays DC, Guiler RC, et al. Inhibition of elimination of caffeine by disulfiram in normal subjects and recovering alcoholics. Clin Pharmacol Ther 1986;39:265-70.
- Dews PB, O'Brien CP, Bergman J. Caffeine: behavioral effects of withdrawal and related issues. Food Chem Toxicol 2002;40:1257-61.
- Holmgren P, Norden-Pettersson L, Ahlner J. Caffeine fatalities--four case reports. Forensic Sci Int 2004;139:71-3.
- Chou T. Wake up and smell the coffee. Caffeine, coffee, and the medical consequences. West J Med 1992;157:544-53.
- Howell LL, Coffin VL, Spealman RD. Behavioral and physiological effects of xanthines in nonhuman primates. Psychopharmacology (Berl) 1997;129:1-14.
- Rakic V, Beilin LJ, Burke V. Effect of coffee and tea drinking on postprandial hypotension in older men and women. Clin Exp Pharmacol Physiol 1996;23:559-63.
- Heseltine D, Dakkak M, woodhouse K, et al. The effect of caffeine on postprandial hypotension in the elderly. J Am Geriatr Soc 1991;39:160-4.
- Castellanos FX, Rapoport JL. Effects of caffeine on development and behavior in infancy and childhood: a review of the published literature. Food Chem Toxicol 2002;40:1235-42.
- Institute of Medicine. Caffeine for the Sustainment of Mental Task Performance: Formulations for Military Operations. Washington, DC: National Academy Press, 2001. Available at: http://books.nap.edu/books/0309082587/html/index.html.
- Zheng XM, Williams RC. Serum caffeine levels after 24-hour abstention: clinical implications on dipyridamole Tl myocardial perfusion imaging. J Nucl Med Technol 2002;30:123-7.
- Aqel RA, Zoghbi GJ, Trimm JR, et al. Effect of caffeine administered intravenously on intracoronary-administered adenosine-induced coronary hemodynamics in patients with coronary artery disease. Am J Cardiol 2004;93:343-6.
- Underwood DA. Which medications should be held before a pharmacologic or exercise stress test? Cleve Clin J Med 2002;69:449-50.
- Smith A. Effects of caffeine on human behavior. Food Chem Toxicol 2002;40:1243-55.
- Stanek EJ, Melko GP, Charland SL. Xanthine interference with dipyridamole-thallium-201 myocardial imaging. Pharmacother 1995;29:425-7.
- Carrillo JA, Benitez J. Clinically significant pharmacokinetic interactions between dietary caffeine and medications. Clin Pharmacokinet 2000;39:127-53.
- Wahllander A, Paumgartner G. Effect of ketoconazole and terbinafine on the pharmacokinetics of caffeine in healthy volunteers. Eur J Clin Pharmacol 1989;37:279-83.
- Sanderink GJ, Bournique B, Stevens J, et al. Involvement of human CYP1A isoenzymes in the metabolism and drug interactions of riluzole in vitro. Pharmacol Exp Ther 1997;282:1465-72.
- Brown NJ, Ryder D, Branch RA. A pharmacodynamic interaction between caffeine and phenylpropanolamine. Clin Pharmacol Ther 1991;50:363-71.
- Abernethy DR, Todd EL. Impairment of caffeine clearance by chronic use of low-dose oestrogen-containing oral contraceptives. Eur J Clin Pharmacol 1985;28:425-8.
- May DC, Jarboe CH, VanBakel AB, Williams WM. Effects of cimetidine on caffeine disposition in smokers and nonsmokers. Clin Pharmacol Ther 1982;31:656-61.
- Nawrot P, Jordan S, Eastwood J, et al. Effects of caffeine on human health. Food Addit Contam 2003;20:1-30.
- Massey LK, Whiting SJ. Caffeine, urinary calcium, calcium metabolism and bone. J Nutr 1993;123:1611-4.
- Infante S, Baeza ML, Calvo M, et al. Anaphylaxis due to caffeine. Allergy 2003;58:681-2.
- Maron DJ, Lu GP, Cai NS, et al. Cholesterol-lowering effect of a theaflavin-enriched green tea extract: a randomized controlled trial. Arch Intern Med 2003;163:1448-53.
- Greenblatt DJ, von Moltke LL, Perloff ES, et al. Interaction of flurbiprofen with cranberry juice, grape juice, tea, and fluconazole: in vitro and clinical studies. Clin Pharmacol Ther 2006;79:125-33.
- Nix D, Zelenitsky S, Symonds W, et al. The effect of fluconazole on the pharmacokinetics of caffeine in young and elderly subjects. Clin Pharmacol Ther 1992;51:183.
- Johnell O, Gullberg B, Kanis JA. Risk factors for hip fracture in European women: the MEDOS Study. Mediterranean Osteoporosis Study. J Bone Miner Res 1995;10:1802-15.
- Kockler DR, McCarthy MW, Lawson CL. Seizure activity and unresponsiveness after hydroxycut ingestion. Pharmacotherapy 2001;21:647-51.
- Grandjean AC, Reimers KJ, Bannick KE, Haven MC. The effect of caffeinated, non-caffeinated, caloric and non-caloric beverages on hydration. J Am Coll Nutr 2000;19:591-600.
- Kamimori GH, Penetar DM, Headley DB, et al. Effect of three caffeine doses on plasma catecholamines and alertness during prolonged wakefulness. Eur J Clin Pharmacol 2000;56:537-44.
- Dreher HM. The effect of caffeine reduction on sleep quality and well-being in persons with HIV. J Psychosom Res 2003;54:191-8.
- Massey LK. Is caffeine a risk factor for bone loss in the elderly? Am J Clin Nutr 2001;74:569-70.
- Warburton DM, Bersellini E, Sweeney E. An evaluation of a caffeinated taurine drink on mood, memory and information processing in healthy volunteers without caffeine abstinence. Psychopharmacology (Berl) 2001;158:322-8.
- Nehlig A, Debry G. Consequences on the newborn of chronic maternal consumption of coffee during gestation and lactation: a review. J Am Coll Nutr 1994;13:6-21.
- McGowan JD, Altman RE, Kanto WP Jr. Neonatal withdrawal symptoms after chronic maternal ingestion of caffeine. South Med J 1988;81:1092-4.
- Bara AI, Barley EA. Caffeine for asthma. Cochrane Database Syst Rev 2001;4:CD001112.
- Bracken MB, Triche EW, Belanger K, et al. Association of maternal caffeine consumption with decrements in fetal growth. Am J Epidemiol 2003;157:456-66.
- Temme EH, Van Hoydonck PG. Tea consumption and iron status. Eur J Clin Nutr 2002;56:379-86.
- Checkoway H, Powers K, Smith-Weller T, et al. Parkinson's disease risks associated with cigarette smoking, alcohol consumption, and caffeine intake. Am J Epidemiol 2002;155:732-8.
- Michels KB, Holmberg L, Bergkvist L, Wolk A. Coffee, tea, and caffeine consumption and breast cancer incidence in a cohort of Swedish women. Ann Epidemiol 2002;12:21-6.
- Su LJ, Arab L. Tea consumption and the reduced risk of colon cancer -- results from a national prospective cohort study. Public Health Nutr 2002;5:419-25.
- Terry P, Wolk A. Tea consumption and the risk of colorectal cancer in Sweden. Nutr Cancer 2001;39:176-9.
- Leung LK, Su Y, Chen R, et al. Theaflavins in black tea and catechins in green tea are equally effective antioxidants. J Nutr 2001;131:2248-51.
- de Maat MP, Pijl H, Kluft C, Princen HM. Consumption of black and green tea had no effect on inflammation, haemostasis and endothelial markers in smoking healthy individuals. Eur J Clin Nutr 2000;54:757-63.
- Hodgson JM, Croft KD, Mori TA, et al. Regular ingestion of tea does not inhibit in vivo lipid peroxidation in humans. J Nutr 2002;132:55-8.
- Zhang M, Binns CW, Lee AH. Tea consumption and ovarian cancer risk: a case-control study in China. Cancer Epidemiol Biomarkers Prev 2002;11:713-8.
- Choi YT, Jung CH, Lee SR, et al. The green tea polyphenol (-)-epigallocatechin gallate attenuates beta-amyloid-induced neurotoxicity in cultured hippocampal neurons. Life Sci 2001;70:603-14.
- Tajima K, Tominaga S. Dietary habits and gastro-intestinal cancers: a comparative case-control study of stomach and large intestinal cancers in Nagoya, Japan. Jpn J Cancer Res 1985;76:705-16.
- Inoue M, Tajima K, Hirose K, et al. Tea and coffee consumption and the risk of digestive tract cancers: data from a comparative case-referent study in Japan. Cancer Causes Control 1998;9:209-16.
- Horner NK, Lampe JW. Potential mechanisms of diet therapy for fibrocystic breast conditions show inadequate evidence of effectiveness. J Am Diet Assoc 2000;100:1368-80.
- Duffy SJ, Vita JA, Holbrook M, et al. Effect of acute and chronic tea consumption on platelet aggregation in patients with coronary artery disease. Arterioscler Thromb Vasc Biol 2001;21:1084-9.
- Zijp IM, Korver O, Tijburg LB. Effect of tea and other dietary factors on iron absorption. Crit Rev Food Sci Nutr 2000;40:371-98.
- Bell DG, Jacobs I, Ellerington K. Effect of caffeine and ephedrine ingestion on anaerobic exercise performance. Med Sci Sports Exerc 2001;33:1399-403.
- Avisar R, Avisar E, Weinberger D. Effect of coffee consumption on intraocular pressure. Ann Pharmacother 2002;36:992-5.
- Shahrzad S, Aoyagi K, Winter A, et al. Pharmacokinetics of gallic acid and its relative bioavailability from tea in healthy humans. J Nutr 2001;131:1207-10.
- Geleijnse JM, Witteman JC, Launer LJ, et al. Tea and coronary heart disease: protection through estrogen-like activity? Arch Intern Med 2000;160:3328-9.
- Peters U, Poole C, Arab L. Does tea affect cardiovascular disease? A meta-analysis. Am J Epidemiol 2001;154:495-503.
- Mukamal KJ, Maclure M, Muller JE, et al. Tea consumption and mortality after acute myocardial infarction. Circulation 2002;105:2476-81.
- Geleijnse JM, Launer LJ, van der Kuip DA, et al. Inverse association of tea and flavonoid intakes with incident myocardial infarction: the Rotterdam Study. Am J Clin Nutr 2002;75:880-6.
- Cronin JR. Green tea extract stokes thermogenesis: will it replace ephedra? Altern Comp Ther 2000;6:296-300.
- Ferrini RL, Barrett-Connor E. Caffeine intake and endogenous sex steroid levels in postmenopausal women. The Rancho Bernardo Study. Am J Epidemiol 1996:144:642-4.
- Hartman TJ, Tangrea JA, Pietinen P, et al. Tea and coffee consumption and risk of colon and rectal cancer in middle-aged Finnish men. Nutr Cancer 1998;31:41-8.
- Olthof MR, Hollman PC, Zock PL, Katan MB. Consumption of high doses of chlorogenic acid, present in coffee, or of black tea increases plasma total homocysteine concentrations in humans. Am J Clin Nutr 2001;73:532-8.
- Ardlie NG, Glew G, Schultz BG, Schwartz CJ. Inhibition and reversal of platelet aggregation by methyl xanthines. Thromb Diath Haemorrh 1967;18:670-3.
- Ali M, Afzal M. A potent inhibitor of thrombin stimulated platelet thromboxane formation from unprocessed tea. Prostaglandins Leukot Med 1987;27:9-13.
- Haller CA, Benowitz NL. Adverse cardiovascular and central nervous system events associated with dietary supplements containing ephedra alkaloids. N Engl J Med 2000;343:1833-8.
- Hegarty VM, May HM, Khaw K. Tea drinking and bone mineral density in older women. Am J Clin Nutr 2000;71:1003-7.
- Sinclair CJ, Geiger JD. Caffeine use in sports. A pharmacological review. J Sports Med Phys Fitness 2000;40:71-9.
- Hodgson JM, Puddey IB, Croft KD, et al. Acute effects of ingestion of black and green tea on lipoprotein oxidation. Am J Clin Nutr 2000;71:1103-7.
- Leenen R, Roodenburg AJ, Tijburg LB, et al. A single dose of tea with or without milk increases plasma antioxidant activity in humans. Eur J Clin Nutr 2000;54:87-92.
- American Academy of Pediatrics. The transfer of drugs and other chemicals into human milk (RE9403). Available at: http://aappolicy.aappublications.org/cgi/reprint/pediatrics;108/3/776.pdf.
- Lloyd T, Johnson-Rollings N, Eggli DF, et al. Bone status among postmenopausal women with different habitual caffeine intakes: a longitudinal investigation. J Am Coll Nutr 2000;19:256-61.
- Watson JM, Jenkins EJ, Hamilton P, et al. Influence of caffeine on the frequency and perception of hypoglycemia in free-living patients with type 1 diabetes. Diabetes Care 2000;23:455-9.
- Ross GW, Abbott RD, Petrovitch H, et al. Association of coffee and caffeine intake with the risk of parkinson disease. JAMA 2000;283:2674-9.
- Hagg S, Spigset O, Mjorndal T, Dahlqvist R. Effect of caffeine on clozapine pharmacokinetics in healthy volunteers. Br J Clin Pharmacol 2000;49:59-63.
- Electronic Code of Federal Regulations. Title 21. Part 182 -- Substances Generally Recognized As Safe. Available at: http://ecfr.gpoaccess.gov/cgi/t/text/text-idx?c=ecfr&sid= 786bafc6f6343634fbf79fcdca7061e1&rgn=div5&view= text&node=21:184.108.40.206.13&idno=21
- Williams MH, Branch JD. Creatine supplementation and exercise performance: an update. J Am Coll Nutr 1998;17:216-34.
- Briggs GB, Freeman RK, Yaffe SJ. Drugs in Pregnancy and Lactation. 5th ed. Philadelphia, PA: Lippincott Williams & Wilkins; 1998.
- Hindmarch I, Quinlan PT, Moore KL, Parkin C. The effects of black tea and other beverages on aspects of cognition and psychomotor performance. Psychopharmacol 1998;139:230-8.
- Sesso HD, Gaziano JM, Buring JE, et al. Coffee and tea intake and the risk of myocardial infarction. Am J Epidemiol 1999;149:162-7.
- Durlach PJ. The effects of a low dose of caffeine on cognitive performance. Psychopharmacology (Berl) 1998;140:116-9.
- Kaegi E. Unconventional therapies for cancer: 2. Green tea. The Task Force on Alternative Therapies of the Canadian Breast Cancer Research Initiative. CMAJ 1998;158:1033-5.
- Curhan GC, Willett WC, Speizer FE, Stamfer MJ. Beverage use and risk of kidney stones in women. Ann Intern Med 1998;128:534-40.
- Geleijnse JM, Launer LJ, Hofman A, et al. Tea flavonoids may protect against atherosclerosis: the Rotterdam Study. Arch Intern Med 1999;159:2170-4.
- FDA. Proposed rule: dietary supplements containing ephedrine alkaloids. Available at: www.verity.fda.gov (Accessed 25 January 2000).
- Dews PB, Curtis GL, Hanford KJ, O'Brien CP. The frequency of caffeine withdrawal in a population-based survey and in a controlled, blinded pilot experiment. J Clin Pharmacol 1999;39:1221-32.
- Nurminen ML, Niittynen L, Korpela R, Vapaatalo H. Coffee, caffeine and blood pressure: a critical review. Eur J Clin Nutr 1999;53:831-9.
- Migliardi JR, Armellino JJ, Friedman M, et al. Caffeine as an analgesic adjuvant in tension headache. Clin Pharmacol Ther 1994;56:576-86.
- Pollock BG, Wylie M, Stack JA, et al. Inhibition of caffeine metabolism by estrogen replacement therapy in postmenopausal women. J Clin Pharmacol 1999;39:936-40.
- Wemple RD, Lamb DR, McKeever KH. Caffeine vs caffeine-free sports drinks: effects on urine production at rest and during prolonged exercise. Int J Sports Med 1997;18:40-6.
- Stookey JD. The diuretic effects of alcohol and caffeine and total water intake misclassification. Eur J Epidemiol 1999;15:181-8.
- Fernandes O, Sabharwal M, Smiley T, et al. Moderate to heavy caffeine consumption during pregnancy and relationship to spontaneous abortion and abnormal fetal growth: a meta-analysis. Reprod Toxicol 1998;12:435-44.
- Eskenazi B. Caffeine—filtering the facts. N Engl J Med 1999;341:1688-9.
- Klebanoff MA, Levine RJ, DerSimonian R, et al. Maternal serum paraxanthine, a caffeine metabolite, and the risk of spontaneous abortion. N Engl J Med 1999;341:1639-44.
- The National Toxicology Program (NTP). Caffeine. Center for the Evaluation of Risks to Human Reproduction (CERHR). Available at: http://cerhr.niehs.nih.gov/common/caffeine.html.
- Rapuri PB, Gallagher JC, Kinyamu HK, Ryschon KL. Caffeine intake increases the rate of bone loss in elderly women and interacts with vitamin D receptor genotypes. Am J Clin Nutr 2001;74:694-700.
- Chiu KM. Efficacy of calcium supplements on bone mass in postmenopausal women. J Gerontol A Biol Sci Med Sci 1999;54:M275-80.
- Vandeberghe K, Gillis N, Van Leemputte M, et al. Caffeine counteracts the ergogenic action of muscle creatine loading. J Appl Physiol 1996;80:452-7.
- Wallach J. Interpretation of Diagnostic Tests. A synopsis of Laboratory Medicine. Fifth ed; Boston, MA: Little Brown, 1992.
- Hodgson JM, Puddey IB, Burke V, et al. Effects on blood pressure of drinking green and black tea. J Hypertens 1999;17:457-63.
- Wakabayashi K, Kono S, Shinchi K, et al. Habitual coffee consumption and blood pressure: A study of self-defense officials in Japan. Eur J Epidemiol 1998;14:669-73.
- Vahedi K, Domingo V, Amarenco P, Bousser MG. Ischemic stroke in a sportsman who consumed MaHuang extract and creatine monohydrate for bodybuilding. J Neurol Neurosurg Psychiatr 2000;68:112-3.
- Joeres R, Klinker H, Heusler H, et al. Influence of mexiletine on caffeine elimination. Pharmacol Ther 1987;33:163-9.
- Ascherio A, Zhang SM, Hernan MA, et al. Prospective study of caffeine intake and risk of Parkinson's disease in men and women. Proceedings 125th Ann Mtg Am Neurological Assn. Boston, MA: 2000;Oct 15-18:42 (abstract 53).
- Merhav H, Amitai Y, Palti H, Godfrey S. Tea drinking and microcytic anemia in infants. Am J Clin Nutr 1985;41:1210-3.
- Kulhanek F, Linde OK, Meisenberg G. Precipitation of antipsychotic drugs in interaction with coffee or tea. Lancet 1979;2:1130.
- Lasswell WL Jr, Weber SS, Wilkins JM. In vitro interaction of neuroleptics and tricylic antidepressants with coffee, tea, and gallotannic acid. J Pharm Sci 1984;73:1056-8.
- Jefferson JW. Lithium tremor and caffeine intake: two cases of drinking less and shaking more. J Clin Psychiatry 1988;49:72-3.
- Mester R, Toren P, Mizrachi I, et al. Caffeine withdrawal increases lithium blood levels. Biol Psychiatry 1995;37:348-50.
- Healy DP, Polk RE, Kanawati L, et al. Interaction between oral ciprofloxacin and caffeine in normal volunteers. Antimicrob Agents Chemother 1989;33:474-8.
- Carbo M, Segura J, De la Torre R, et al. Effect of quinolones on caffeine disposition. Clin Pharmacol Ther 1989;45:234-40.
- Harder S, Fuhr U, Staib AH, Wolff T. Ciprofloxacin-caffeine: a drug interaction established using in vivo and in vitro investigations. Am J Med 1989;87:89S-91S.
- Foster S, Duke JA. Eastern/Central Medicinal Plants. New York, NY: Houghton Mifflin Co., 1990.
- Hertog MGL, Sweetnam PM, Fehily AM, et al. Antioxidant flavonols and ischemic heart disease in a Welsh population of men: the Caerphilly Study. Am J Clin Nutr 1997;65:1489-94.
- McKevoy GK, ed. AHFS Drug Information. Bethesda, MD: American Society of Health-System Pharmacists, 1998.
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