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Coffee

Coffee is a beverage made from the roasted beans of the Coffea Arabica bush. People drink coffee to relieve mental and physical fatigue and improve mental alertness. Coffee is also used to prevent Parkinson's disease, gallstones, type 2 diabetes, stomach cancer, lung cancer and breast cancer. Other uses include the treatment of headaches, low blood pressure, obesity and attention deficit hyperactivity disorder (ADHD). Rectally, coffee is used as an enema to treat cancer. Coffee is also used as part of the "Gerson Therapy". In "Gerson Therapy", cancer patients are treated with coffee daily in the form of enemas every four hours. During treatment, patients follow a diet consisting of liver, vegetables and a range of medications including potassium, pepsin, Lugol's solution, niacin, pancreatin and thyroid extracts. The "Gerson Therapy" is not considered an accepted medical procedure in America.

How does coffee work?

Coffee contains caffeine. Caffeine works by stimulating the central nervous system, heart and muscles.

How effective is coffee?

Coffee is likely to be effective for the following applications:

  • Improving mental alertness: consuming coffee and other beverages containing caffeine throughout the day appears to improve alertness and promote clear thinking. Caffeine can also improve alertness after sleep deprivation. Combining caffeine with glucose as an energy drink appears to improve mental performance better than caffeine or glucose alone.

Coffee may be effective for the following applications:

  • Reducing the risk of colorectal cancer. Some research suggests that consuming more than 3 cups of coffee per day could significantly reduce the risk of rectal cancer.
  • Preventing dizziness in older people with low blood pressure after eating a meal (postprandial hypotension): Consumption of caffeinated beverages such as coffee appears to increase blood pressure in older people who suffer from dizziness after eating.
  • Preventing or delaying Parkinson's disease: There is evidence that people who drink caffeinated beverages such as coffee, tea and cola have a reduced risk of Parkinson's disease. In men, this effect seems to depend on the amount of coffee consumed. Men who drink the most coffee (3 to 4 cups) per day seem to show the greatest reduction in risk. However, even 1 or 2 cups of coffee per day seem to significantly reduce the risk of Parkinson's in men. In women, the effect does not seem to depend so much on the amount of caffeine consumed. Moderate consumption of 1 to 3 cups of caffeinated coffee provides the greatest reduction in Parkinson's risk in women. Interestingly, coffee does not appear to help prevent Parkinson's in people who smoke.
  • Prevention of gallstones: Consuming caffeinated beverages including coffee, which provides at least 400 mg of caffeine per day, appears to reduce the risk of developing gallstones. The higher the caffeine intake, the lower the risk. Consuming 800 mg of caffeine per day leads to the greatest reduction in risk.
  • Prevention of type 2 diabetes: The consumption of caffeinated coffee appears to significantly reduce the risk of developing type 2 diabetes. As caffeine consumption increases, the risk of developing diabetes decreases. However, this effect appears to be different for different groups of people. In North American adults, consumption of 6 or more cups of coffee per day is associated with a 54% reduction in the risk of diabetes in men and 29% in women. In European adults, consuming 5 to 6 cups of coffee per day reduces the risk of diabetes by 61% in women and 30% in men. Consuming 10 or more cups of coffee per day reduces the risk of diabetes 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 one cup or less per day. Decaffeinated coffee does not appear to reduce the risk of diabetes.

Coffee may be ineffective for the following applications:

  • Reducing the risk of digestive tract cancers including esophageal cancer, stomach cancer and colorectal cancer.
  • Reducing the risk of breast cancer

There is not enough scientific data to make a statement about the effectiveness of coffee in the following applications:

  • Lung cancer: some research concludes that caffeinated coffee consumption may help prevent lung cancer, but other research contradicts these findings. It is too early to make a definitive statement. In the meantime, some research suggests that drinking decaffeinated coffee may help prevent lung cancer.
  • Gout: There is evidence that both caffeinated and decaffeinated coffee seem to help prevent gout, but caffeinated coffee seems to work better.
  • Improving thinking ability: There is evidence that drinking more coffee over the course of a lifetime may improve thinking ability in women over 80.

Further scientific research is needed to evaluate the effectiveness of coffee in these applications.

Safety and side effects

Coffee is safe and harmless for most adults. Consuming more than 6 cups of coffee per day could cause "caffeinism" with symptoms such as anxiety or restlessness. People who drink a lot of coffee may need more and more coffee to achieve the same effect. They can also develop an addiction to the point where they may experience withdrawal symptoms if they suddenly stop drinking coffee. Caffeinated coffee can cause insomnia, nervousness and restlessness, stomach problems, nausea and vomiting, increased heart and breathing rate and other side effects. Drinking large amounts of coffee can also cause headaches, anxiety, agitation, ringing in the ears and an irregular heartbeat. Drinking unfiltered coffee can increase total cholesterol, LDL cholesterol and triglyceride levels in the blood. This could increase the risk of developing heart disease. Using a coffee filter helps to reduce these effects on cholesterol levels. There are concerns that consuming more than 5 cups of coffee a day may not be safe and harmless for people with heart disease. However, for people who do not suffer from heart disease, daily consumption of several cups of coffee does not appear to increase the risk of developing heart disease. There are also concerns that drinking coffee occasionally could trigger a heart attack in some people. People who usually drink no more than one cup of coffee a day and also have several risk factors for heart disease appear to have an increased risk of having a heart attack within an hour of drinking coffee. People who regularly drink larger amounts of coffee do not appear to have this risk. Coffee may not be safe and harmless when administered rectally as an enema. Coffee enemas have been linked to cases of serious side effects including death.

Precautions and warnings

Pregnancy and lactation: Caffeinated coffee is probably safe and safe for pregnant women in amounts of 2 cups per day or less. This amount of coffee provides about 200 mg of caffeine. However, consumption of larger amounts of coffee is associated with an increased risk of miscarriage, premature birth and low birth weight. These risks appear to increase with the amount of coffee the mother drinks during pregnancy. Consuming 1 to 2 cups of coffee per day appears to be safe and harmless for breastfeeding mothers and their babies. However, coffee in larger quantities can irritate the child's digestive tract and also cause sleep problems and irritability.

Children: The consumption of caffeinated coffee may not be safe for children. The side effects associated with coffee are usually more severe in children.

Anxiety disorders: The caffeine in coffee may exacerbate anxiety disorders.

Bleeding disorders: There are concerns that coffee may worsen bleeding disorders.

Heart disease: Drinking unfiltered coffee can increase the amount of cholesterol and other fats in the blood and also raise homocysteine levels. All of these are associated with an increased risk of developing heart disease. Some research suggests a link between heart attacks and coffee consumption.

Diabetes: Some research suggests that the caffeine in coffee may alter the way diabetics process sugar. It has been reported that caffeine can cause both increases and decreases in blood sugar levels. For this reason, diabetics should use caffeine with caution and monitor their blood sugar levels carefully.

Diarrhea: The caffeine in coffee can aggravate diarrhea, especially in large amounts.

Irritable bowel syndrome: In addition to diarrhea, the caffeine contained in coffee can also aggravate the symptoms of irritable bowel syndrome, especially in large quantities.

Glaucoma: The consumption of caffeinated coffee can increase intraocular pressure. This increase begins within 30 minutes and lasts for at least 90 minutes.

High blood pressure: Drinking caffeinated coffee may increase blood pressure in people with high blood pressure. However, this effect may be weaker in people who drink coffee regularly.

Osteoporosis: Consuming coffee can increase the amount of calcium excreted in the urine. This could weaken the bones. If you suffer from osteoporosis, you should therefore limit your caffeine intake to less than 300 mg per day (about 2 to 3 cups of coffee). Taking calcium supplements could help to compensate for the loss of calcium. Postmenopausal women who suffer from a hereditary inability to process vitamin D normally should be particularly careful when using caffeine.

Interactions

Coffee should not be consumed in conjunction with the following medications:

Ephedrine

Stimulants accelerate the function of the nervous system. The caffeine contained in coffee and ephedrine are both stimulants. Consuming coffee in combination with ephedrine can cause excessive stimulation and, in some cases, serious side effects and heart problems. For this reason, ephedrine and products containing caffeine should not be taken at the same time.

Caution should be exercised when consuming coffee in conjunction with the following medications:

Adenosine

The caffeine contained in coffee could block the effects of adenosine. Adenosine is often used by doctors to perform a test of the heart called a cardiac stress test. Due to the possible interactions, you should stop drinking coffee and other caffeinated products at least 24 hours before such a test.

Alcohol

The body breaks down the caffeine contained in coffee in order to be able to excrete it. Alcohol can reduce the rate at which the body breaks down caffeine. Drinking alcohol with coffee can increase the risk of caffeine side effects including shakiness, headaches, increased heart rate and others.

Alendronate

Coffee can reduce the amount of alendronate absorbed by the body. Drinking coffee in combination with alendronate may reduce the effectiveness of alendronate. Therefore, you should not drink coffee two hours before and after taking alendronate.

Antibiotics

The body breaks down the caffeine contained in coffee in order to be able to excrete it. Some antibiotics can reduce the rate at which the body breaks down caffeine. Taking these antibiotics in combination with caffeine can increase the risk of caffeine side effects including shakiness, headaches, increased heart rate and others.

Clozapine

The body breaks down clozapine in order to excrete it. The caffeine in coffee may reduce the rate at which the body breaks down clozapine. The consumption of coffee in combination with clozapine may increase the effects and side effects of clozapine.

Dipyridamole

The caffeine contained in coffee could block the effects of dipyridamole. Dipyridamole is often used by doctors to perform a test of the heart called a cardiac stress test. Due to the possible interactions, you should stop drinking coffee and other caffeinated products at least 24 hours before such a test.

Oestrogens

The body breaks down the caffeine contained in coffee in order to excrete it. Estrogen can reduce the rate at which the body breaks down caffeine. Taking estrogen in combination with caffeine could cause shakiness, headaches, rapid heartbeat and other side effects. For this reason, you should limit your caffeine intake if you are taking estrogens.

Fluvoxamine

The body breaks down the caffeine contained in coffee in order to be able to excrete it. Fluvoxamine can reduce the rate at which the body breaks down caffeine. Taking fluvoxamine in combination with coffee can increase the effects and side effects of caffeine.

Levothyroxine

Coffee consumption may reduce the amount of levothyroxine absorbed by the body when taken orally. This can reduce the effect of levothyroxine. For this reason, you should not drink coffee one hour before and after taking levothyroxine.

Lithium

The caffeine contained in coffee can increase the rate at which the body excretes lithium. If you consume products that contain caffeine and are taking lithium, you should slowly reduce your intake of caffeine-containing products. Stopping caffeine intake too quickly can increase the side effects of lithium.

Medication for depression ( monoamine oxidase inhibitors / MAOI)

Coffee contains caffeine. Caffeine can stimulate the body. Some medications used for depression can also stimulate the body. The consumption of coffee in combination with these medications could result in excessive stimulation. This could cause serious side effects including rapid heartbeat, high blood pressure, nervousness and more.

Medication for depression (tricyclic antidepressants)

Coffee contains chemicals called tannins. Tannins can bind to many medications and reduce their absorption in the body. To prevent this interaction, you should not drink coffee one hour before and two hours after taking tricyclic antidepressants.

Medications that slow down blood clotting

Coffee could slow down blood clotting. Drinking coffee in combination with medications that also slow down blood clotting could increase the risk of bleeding and the tendency to bruise.

Some medications that can slow blood clotting include aspirin, diclofenac (Voltaren), ibuprofen, naproxen and others.

Phenothiazines

Coffee contains chemicals known as tannins. Tannins can bind to many medications and reduce their absorption in the body. To prevent this under-action, you should not drink coffee one hour before and two hours after taking phenothiazines.

Phenylpropanolamine

The caffeine contained in coffee can stimulate the body. Phenylpropanolamine can also stimulate the body. Drinking coffee in combination with phenylpropanolamine could result in excessive stimulation and increase the heart rate, raise blood pressure and cause nervousness.

Riluzole

The body breaks down riluzole in order to excrete it. The consumption of coffee can reduce the rate at which the body breaks down riluzole and thus increase the effects and side effects of riluzole.

Stimulants

Stimulants accelerate the function of the nervous system. By accelerating the nervous system, stimulants can speed up the heart rate and cause a shaky feeling. The caffeine contained in coffee can also accelerate the functioning of the nervous system. Consuming coffee in combination with stimulants can cause serious side effects including accelerated heart rate and increased blood pressure. For this reason, stimulants and coffee should not be consumed at the same time.

Theophylline

Coffee contains caffeine. Caffeine acts in a similar way to theophylline. In addition, caffeine can reduce the rate at which the body breaks down theophylline. Consuming coffee in conjunction with taking theophylline may increase the effects and side effects of theophylline.

You should be vigilant when consuming coffee in combination with the following medications:

The contraceptive pill

The body breaks down the caffeine contained in coffee in order to be able to excrete it. The contraceptive pill can reduce the rate at which the body breaks down caffeine. Consuming coffee in combination with the contraceptive pill can cause shakiness, headaches, rapid heartbeat and other side effects.

Cimetidine

The body breaks down the caffeine contained in coffee in order to be able to excrete it. Cimetidine can reduce the rate at which the body breaks down caffeine. Taking cimetidine with coffee may increase the risk of caffeine side effects including shakiness, headaches, increased heart rate and others.

Fluconazole

The body breaks down the caffeine contained in coffee in order to excrete it. Fluconazole can reduce the rate at which the body breaks down caffeine. Taking fluconazole with coffee may increase the risk of caffeine side effects including insomnia, shakiness, headaches, increased heart rate and more.

Diabetes medication

Coffee may increase blood sugar levels. Diabetes medications are used to lower blood sugar levels. By increasing blood sugar levels, coffee could reduce the effectiveness of diabetes medication. For this reason, blood sugar levels should be carefully monitored. It is possible that the dosage of diabetes medication may need to be adjusted.

Mexiletine

The body breaks down the caffeine contained in coffee in order to be able to excrete it. Mexiletine can reduce the rate at which the body breaks down caffeine. Taking mexiletine in combination with coffee can increase the effects and side effects of caffeine.

Terbinafine

The body breaks down the caffeine contained in coffee in order to be able to excrete it. Terbinafine can reduce the rate at which the body breaks down caffeine. Taking terbinafine with coffee may increase the risk of caffeine side effects including insomnia, shakiness, headaches, increased heart rate and others.

Dosage

The following dosages have been investigated in scientific studies:

Oral:

  • For headaches or to improve mental alertness: the typical dose of caffeine is up to 250 mg per day, which is equivalent to about 2 cups of coffee.
  • To prevent Parkinson's disease: Three to four cups of caffeinated coffee per day or 421 to 2716 mg of total caffeine. However, a significantly lower risk of developing Parkinson's has already been associated with 124 to 208 mg of caffeine (about one to two cups of coffee). For women, a more moderate coffee consumption of one to three cups of coffee per day seems to be best.
  • To prevent gallstones: 400 mg or more of caffeine per day (three or more cups of coffee). However, consuming 800 mg of caffeine per day (6 cups of coffee or more) appears to be most effective.
  • To prevent type 2 diabetes: 900 mg of caffeine per day (7 or more cups of coffee per day) in the long term.

Filtered coffee should be used to prevent some of the unwanted side effects. The choice of coffee powder, the ratio of coffee to water, the degree of grinding and other factors determine the taste and strength of the coffee.

Caffeine content per average cup of coffee: filter coffee: 100 to 150 mg caffeine, soluble coffee: 85 to 100 mg caffeine, decaffeinated coffee: around 8 mg caffeine. Dark roasted coffee contains less caffeine due to the roasting process

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