Cafe, Café, Café Arabica, Café Robusta, Caffea, Coffea arabica, Coffea arnoldiana, Coffea bukobensis, Coffea canephora, Coffea Cruda, Coffea liberica, Coffea robusta, Espresso, Expresso, Java, Mocha.
Coffee is a drink made from coffee beans, which are the roasted fruit of the Coffea arabica bush.
People drink coffee to relieve mental and physical fatigue and to increase mental alertness. Coffee is also used to prevent Parkinson's disease, gallstones, type 2 diabetes, gastrointestinal cancer, lung cancer, and breast cancer. Other uses include treatment of headache, low blood pressure, obesity, and attention deficit-hyperactivity disorder (ADHD).
Rectally, coffee is used as an enema to treat cancer. Coffee enemas are used as a part of the "Gerson Therapy." In the Gerson Therapy, cancer patients are treated with caffeinated coffee in the form of enemas every four hours on a daily basis. During the treatment people are given a diet of liver, vegetables, and a variety of medicines, including potassium, pepsin, Lugol's solution, niacin, pancreatin, and thyroid extracts. The Gerson Therapy is considered an unacceptable medical practice in the U.S., but continues to be used at The Hospital of the Baja California in Tijuana, Mexico, one mile from the U.S.
How does it work?
Coffee contains caffeine. Caffeine works by stimulating the central nervous system (CNS), heart, and muscles.
Likely Effective for...
- Mental alertness. Drinking coffee and other beverages that contain caffeine throughout the day seems to increase alertness and clear thinking. Caffeine can also improve alertness after sleep deprivation. Combining caffeine with glucose as an "energy drink" seems to improve mental performance better than either caffeine or glucose alone.
Possibly Effective for...
- Reducing the risk of colorectal cancer. Some research suggests that drinking more than 3 cups of coffee daily may significantly reduce the risk of rectal cancer.
- Preventing dizziness in older people caused by low blood pressure after eating a meal (postprandial hypotension). Drinking caffeinated beverages like coffee seems to increase blood pressure in elderly people who experience dizziness after meals.
- Preventing or delaying Parkinson's disease. There is evidence that people who drink caffeinated beverages such as coffee, tea, and cola have a decreased risk of Parkinson's disease. For men, the effect seems to depend on the amount of caffeine consumed. Men who drink the most caffeinated coffee, 28 ounces (three to four cups) per day, seem to have the greatest reduction in risk. But drinking even 1 or 2 cups of coffee cuts their Parkinson's disease risk significantly. In women, the effect does not seem to depend so much on the amount of caffeine consumed. Moderate consumption of caffeinated coffee, 1-3 cups daily, provides the most reduction in risk in women. Interestingly, coffee does not seem to help prevent Parkinson's disease in people who smoke cigarettes.
- Preventing gallstones. Drinking caffeinated beverages, including coffee, that provide at least 400 mg of caffeine per day seems to reduce the risk of developing gallstones. The greater the intake of caffeine, the lower the risk. Drinking 800 mg caffeine per day (four or more cups of coffee) has the greatest reduction in risk.
- Preventing type 2 diabetes. Drinking caffeinated coffee seems to significantly reduce the risk of developing type 2 diabetes. As caffeine consumption goes up, the risk of developing diabetes goes down. But the effect seems to be different in different groups of people. In North American adults, drinking 6 or more cups of coffee per day is associated with a 54% lower risk of developing diabetes in men and a 29% lower risk in women. In European adults, drinking 5-6 cups of coffee per day reduces diabetes risk by 61% in women and 30% in men. Drinking 10 or more cups of coffee per day reduces diabetes risk by 79% in women and 55% in men. Japanese adults who drink 3 or more cups of coffee per day have a 42% lower risk of developing type 2 diabetes compared to those who drink only one cup per day or less. Decaffeinated coffee doesn't seem to lower the risk of getting diabetes.
Possibly Ineffective for...
- Reducing the risk of digestive tract cancers, including esophageal, stomach, and colon cancers.
- Reducing the risk of breast cancer.
Insufficient Evidence to Rate Effectiveness for...
- Lung cancer. Some research concludes that drinking caffeinated coffee may help to prevent lung cancer, but other research disagrees. It's too early to draw firm conclusions. Meanwhile, some research suggests that drinking decaffeinated coffee may help to prevent lung cancer.
- Gout. There is some evidence that both caffeinated and decaffeinated coffee seem to help to prevent gout, but caffeinated coffee works better.
- Improving thinking. There is developing evidence suggesting that drinking more coffee over a lifetime might improve thinking skills among women older than 80 years of age.
- Other conditions.
Natural Medicines Comprehensive Database rates effectiveness based on scientific evidence according to the following scale: Effective, Likely Effective, Possibly Effective, Possibly Ineffective, Likely Ineffective, and Insufficient Evidence to Rate (detailed description of each of the ratings).
Coffee is safe for most adults. Drinking more than 6 cups/day might cause “caffeinism” with symptoms such as anxiety or agitation. People who drink a lot of coffee every day may need to drink more coffee to get the same effects. They may also become “dependent” on coffee to the point that they develop withdrawal symptoms if they suddenly stop drinking it.
Coffee containing caffeine can cause insomnia, nervousness and restlessness, stomach upset, nausea and vomiting, increased heart and breathing rate, and other side effects. Consuming large amounts of coffee might also cause headache, anxiety, agitation, ringing in the ears, and irregular heartbeats.
Drinking unfiltered coffee can increase total cholesterol, low-density lipoprotein (LDL), and levels of another type of blood fat called triglycerides. This might increase the risk of developing heart disease. Using coffee filters helps to reduce these effects on cholesterol.
There is some concern that drinking more than 5 cups of coffee per day might not be safe for people with heart disease. But for people who don't have heart disease, drinking several cups daily does not seem to increase the chance of developing a heart problem.
There is also concern that occasional coffee drinking might trigger a heart attack in some people. People who usually don't drink more than one cup of coffee daily and also have multiple risk factors for heart disease seem to have an increased risk for heart attack within an hour after drinking coffee. But people who regularly drink greater amounts do not seem to have this risk.
Coffee might be unsafe when given rectally as an enema. Coffee enemas have been linked to cases of severe side effects including death.
Drinking 1 or 2 of cups of coffee per day seems to be safe for breast-feeding mothers and their infants. But the caffeine in larger amounts can irritate a nursing infant's digestive tract and also cause sleep problems and irritability.
Children: It may be unsafe for children to drink caffeinated coffee. The side effects associated with caffeine are usually more severe in children than adults.
Anxiety disorders: The caffeine in coffee might make anxiety worse.
Bleeding disorders: There is some concern that coffee might make bleeding disorders worse.
Heart disease: Drinking unfiltered (boiled) coffee increases the amount of cholesterol and other fats in the blood, and also raises the level of homocysteine, all of which are associated with an increased risk of developing heart disease. Some research suggests an association between heart attacks and drinking coffee.
Diabetes: Some research suggests that caffeine contained in coffee might change the way people with diabetes process sugar. Caffeine has been reported to cause increases as well as decreases in blood sugar. Use caffeine with caution if you have diabetes and monitor your blood sugar carefully.
Diarrhea: Coffee contains caffeine. The caffeine in coffee, especially when taken in large amounts, can worsen diarrhea.
Irritable bowel syndrome (IBS): Coffee contains caffeine. The caffeine in coffee, especially when taken in large amounts, can worsen diarrhea and might worsen symptoms of IBS.
Glaucoma: Drinking caffeinated coffee increases pressure inside the eye. The increase starts within 30 minutes and lasts for at least 90 minutes.
High blood pressure: Drinking caffeinated coffee might increase blood pressure in people with high blood pressure. However, this effect might be less in people who drink coffee regularly.
Thinning bones (osteoporosis): Drinking caffeinated coffee can increase the amount of calcium that is flushed out in the urine. This might weaken bones. If you have osteoporosis, limit caffeine consumption to less than 300 mg per day (approximately 2-3 cups of coffee). Taking calcium supplements may help to make up for calcium that is lost. Postmenopausal women who have an inherited condition that keeps them from processing vitamin D normally, should be especially cautious when using caffeine.
EphedrineInteraction Rating: Major Do not take this combination.
Stimulant drugs speed up the nervous system. The caffeine in coffee and ephedrine are both stimulant drugs. Drinking coffee and taking 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.
Adenosine (Adenocard)Interaction Rating: Moderate Be cautious with this combination.Talk with your health provider.
The caffeine in coffee 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 consuming coffee or other caffeine-containing products at least 24 hours before a cardiac stress test.
AlcoholInteraction Rating: Moderate Be cautious with this combination.Talk with your health provider.
The body breaks down the caffeine in coffee to get rid of it. Alcohol can decrease how quickly the body breaks down caffeine. Taking coffee along with alcohol might cause too much caffeine in the bloodstream and caffeine side effects including jitteriness, headache, and fast heartbeat.
Alendronate (Fosamax)Interaction Rating: Moderate Be cautious with this combination.Talk with your health provider.
Coffee can decrease how much alendronate (Fosamax) the body absorbs. Taking coffee and alendronate (Fosamax) at the same time can decrease the effectiveness of alendronate (Fosamax). Don't drink coffee within two hours of taking alendronate (Fosamax).
Antibiotics (Quinolone antibiotics)Interaction Rating: Moderate Be cautious with this combination.Talk with your health provider.
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 coffee 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).
Birth control pills (Contraceptive drugs)Interaction Rating: Moderate Be cautious with this combination.Talk with your health provider.
The body breaks down the caffeine in coffee to get rid of it. Birth control pills can decrease how quickly the body breaks down caffeine. Taking coffee 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.
Clozapine (Clozaril)Interaction Rating: Moderate Be cautious with this combination.Talk with your health provider.
The body breaks down clozapine (Clozaril) to get rid of it. The caffeine in coffee might decrease how fast the body breaks down clozapine (Clozaril). Taking coffee along with clozapine (Clozaril) can increase the effects and side effects of clozapine (Clozaril).
Dipyridamole (Persantine)Interaction Rating: Moderate Be cautious with this combination.Talk with your health provider.
The caffeine in coffee 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 coffee or other caffeine-containing products at least 24 hours before a cardiac stress test.
Disulfiram (Antabuse)Interaction Rating: Moderate Be cautious with this combination.Talk with your health provider.
The body breaks down the caffeine in coffee to get rid of it. Disulfiram (Antabuse) can decrease how quickly the body gets rid of caffeine. Taking coffee along with disulfiram (Antabuse) might increase the effects and side effects of coffee including jitteriness, hyperactivity, irritability, and others.
EstrogensInteraction Rating: Moderate Be cautious with this combination.Talk with your health provider.
The body breaks down the caffeine in coffee to get rid of it. Estrogens can decrease how quickly the body breaks down caffeine. Taking estrogen pills and drinking coffee 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.
Fluvoxamine (Luvox)Interaction Rating: Moderate Be cautious with this combination.Talk with your health provider.
The body breaks down the caffeine in coffee 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.
Levothyroxine (Synthroid, Levothroid, Levoxyl, and others)Interaction Rating: Moderate Be cautious with this combination.Talk with your health provider.
Drinking some types of coffee might reduce the amount of levothyroxine that is absorbed when taken by mouth. This can decrease how well levothyroxine works. Avoid drinking coffee at the same time that you take levothyroxine and for an hour afterwards.
LithiumInteraction Rating: Moderate Be cautious with this combination.Talk with your health provider.
Your body naturally gets rid of lithium. The caffeine in coffee 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)Interaction Rating: Moderate Be cautious with this combination.Talk with your health provider.
Coffee 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.
Medications for depression (MAOIs)Interaction Rating: Moderate Be cautious with this combination.Talk with your health provider.
The caffeine in coffee can stimulate the body. Some medications used for depression can also stimulate the body. Drinking coffee and taking some medications for depression might cause too much stimulation and serious side effects including fast heartbeat, high blood pressure, nervousness, and others.
Medications for depression (Tricyclic antidepressants)Interaction Rating: Moderate Be cautious with this combination.Talk with your health provider.
Coffee contains chemicals called tannins. Tannins can bind to many medications and decrease how much medicine the body absorbs. To avoid this interaction avoid coffee one hour before and two hours after taking medications for depression called tricyclic antidepressants.
Medications that slow blood clotting (Anticoagulant / Antiplatelet drugs)Interaction Rating: Moderate Be cautious with this combination.Talk with your health provider.
Coffee might slow blood clotting. Taking coffee 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.
Pentobarbital (Nembutal)Interaction Rating: Moderate Be cautious with this combination.Talk with your health provider.
The stimulant effects of the caffeine in coffee can block the sleep-producing effects of pentobarbital.
PhenothiazinesInteraction Rating: Moderate Be cautious with this combination.Talk with your health provider.
Coffee contains chemicals called tannins. Tannins can bind to many medications and decrease how much medicine the body absorbs. To avoid this interaction, avoid coffee one hour before and two hours after taking phenothiazine medications.
Some phenothiazine medications include fluphenazine (Permitil, Prolixin), chlorpromazine (Thorazine), haloperidol (Haldol), prochlorperazine (Compazine), thioridazine (Mellaril), and trifluoperazine (Stelazine).
PhenylpropanolamineInteraction Rating: Moderate Be cautious with this combination.Talk with your health provider.
The caffeine in coffee 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.
Riluzole (Rilutek)Interaction Rating: Moderate Be cautious with this combination.Talk with your health provider.
The body breaks down riluzole (Rilutek) to get rid of it. Drinking coffee can decrease how fast the body breaks down riluzole (Rilutek) and increase the effects and side effects of riluzole.
Stimulant drugsInteraction Rating: Moderate Be cautious with this combination.Talk with your health provider.
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 coffee can also speed up the nervous system. Drinking coffee along with stimulant drugs might cause serious problems including increased heart rate and high blood pressure. Avoid taking stimulant drugs along with coffee.
TheophyllineInteraction Rating: Moderate Be cautious with this combination.Talk with your health provider.
The caffeine in coffee works similarly to theophylline. Caffeine can also decrease how quickly the body gets rid of theophylline. Drinking coffee and taking theophylline might increase the effects and side effects of theophylline.
Verapamil (Calan, Covera, Isoptin, Verelan)Interaction Rating: Moderate Be cautious with this combination.Talk with your health provider.
The body breaks down the caffeine in coffee to get rid of it. Verapamil (Calan, Covera, Isoptin, Verelan) can decrease how quickly the body gets rid of caffeine. Drinking coffee and taking verapamil (Calan, Covera, Isoptin, Verelan) can increase the risk of side effects for coffee including jitteriness, headache, and an increased heartbeat.
Cimetidine (Tagamet)Interaction Rating: Minor Be cautious with this combination.Talk with your health provider.
The body breaks down the caffeine in coffee to get rid of it. Cimetidine (Tagamet) can decrease how quickly your body breaks down caffeine. Taking cimetidine (Tagamet) along with coffee might increase the chance of caffeine side effects including jitteriness, headache, fast heartbeat, and others.
Fluconazole (Diflucan)Interaction Rating: Minor Be cautious with this combination.Talk with your health provider.
The body breaks down the caffeine in coffee to get rid of it. Fluconazole (Diflucan) might decrease how quickly the body gets rid of caffeine. Taking fluconazole (Diflucan) and drinking coffee might increase the effects and side effects of coffee including nervousness, anxiety, and insomnia.
Medications for diabetes (Antidiabetes drugs)Interaction Rating: Minor Be cautious with this combination.Talk with your health provider.
Coffee might increase blood sugar. Diabetes medications are used to lower blood sugar. By increasing blood sugar, coffee 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.
Mexiletine (Mexitil)Interaction Rating: Minor Be cautious with this combination.Talk with your health provider.
Coffee 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 coffee might increase the caffeine effects and side effects of coffee.
Terbinafine (Lamisil)Interaction Rating: Minor Be cautious with this combination.Talk with your health provider.
The body breaks down the caffeine in coffee to get rid of it. Terbinafine (Lamisil) can decrease how fast the body gets rid of caffeine and increase the risk of side effects including jitteriness, headache, increased heartbeat, and other effects.
The following doses have been studied in scientific research:
- For headache or improving mental alertness: The typical dose of caffeine is up to 250 mg per day, about 2 cups of coffee.
- For preventing Parkinson's disease: Three to four cups (28 oz) of caffeinated coffee per day or 421 mg to 2716 mg total caffeine. However, a significantly lower risk of developing Parkinson's disease has also been associated with as little as 124 mg to 208 mg of caffeine (approximately one to two cups of coffee). In women, more moderate caffeinated coffee intake, one to three cups per day, seems to be best.
- For preventing gallstone disease: 400 mg or more of caffeine per day (two or more cups of coffee). However, drinking at least 800 mg caffeine per day (four or more cups of coffee) seems to be most effective.
- For preventing type 2 diabetes: 900 mg caffeine per day (6 or more cups of coffee per day) long-term.
Caffeine content of coffee (per average cup): Percolated, 100-150 mg caffeine; instant, 85-100 mg caffeine; and decaffeinated, approximately 8 mg caffeine. Darker roasts contain less caffeine due to the roasting process.
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