May 4, 2016

Coffee

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How does Coffee work?

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

Are there safety concerns?

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.

Special Precautions & Warnings:

Pregnancy and breast-feeding: Caffeinated coffee is probably safe for pregnant women in amounts of 2 cups per day or less. This amount of coffee provides about 200 mg of caffeine. However, drinking more than this amount has been linked to an increased risk of miscarriage, premature birth, and low birth weight. These risks increase as the amount of coffee the mother drinks during pregnancy increases.

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.


Therapeutic Research Faculty copyright

Report Problems to the Food and Drug Administration

You are encouraged to report negative side effects of prescription drugs to the FDA. Visit the FDA MedWatch website or call 1-800-FDA-1088.


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