Caffeine is a drug found naturally in tea and coffee that stimulates the nervous system and can lead to feeling anxious and irritable. In 2000, experts linked caffeine to joint diseases, and people who consume more than 400 mg a day are at risk of painful withdrawal symptoms. More than half of adults between 25 and 39 get their caffeine fix daily from coffee, according to the National Coffee Association. In 2006, Americans spent $2 billion on tea, says the Tea Association.
The number of cups of coffee a person drinks each day might be directly proportional to the risk for developing rheumatoid arthritis, or RA. Researchers from Finland's National Public Health Institute evaluated the health effects of coffee consumption and its association to RA. Drinking four or more cups of coffee a day seems to be the threshold for determining the likelihood of developing the condition. It is not known what role caffeine plays. Rheumatoid arthritis is a debilitating joint-inflammation disorder. Chronic, severe leg pain is just one component of this chronic disease. Night pain in people with RA is a characteristic of a more active disease, according to a 1998 study published in the journal "Annals of Rheumatoid Diseases."
Restless Legs Syndrome
Caffeine has been linked to restless legs syndrome, RLS, a condition that causes pain and discomfort in the legs, especially at night. The National Institute of Neurological Disorders and Stroke suggests cutting back on caffeine to reduce symptoms in people with mild to moderate RLS. Common characteristics of RLS include symptoms occurring while inactive, such as when sufferers are trying to go to sleep, worsening pain in the evening and nighttime leg twitching.
While it might not be as serious as other kinds of withdrawal, caffeine withdrawal is a very real phenomenon and one some experts would like to see classified as a psychiatric disorder, according to CBS News Healthwatch. Symptoms of caffeine withdrawal include muscle pain and stiffness and occur about 12 to 24 hours after the last cup of joe or other caffeine-infused beverage. If your last cup of coffee was 10 a.m. and you go the rest of the day without a fix, it would make sense for cramps to kick in at night. Few people drink enough coffee to experience withdrawal symptoms, however. MayoClinic.com reports that drinking more than four cups a day could put you at risk.
Consuming from 200 to 300 mg of caffeine a day, equivalent to two to four cups of coffee, shouldn't be harmful, according to MayoClinic.com. Heavy caffeine use -- more than 500 mg a day -- can cause insomnia, irritability and muscle tremors. If you don't want to cut down on caffeine, try drinking tea, which has much less caffeine than coffee. Generic, instant tea mix contains about 27 g of the chemical. Many sports drinks, on the other hand, can have more caffeine than coffee, ranging from 74 mg to nearly 300 mg in an 8.4 oz. serving. Most soft drinks contain about 30 to 55 mg. Note that by taking a medication like Exedrin or certain types of Tylenol, you could be popping more than 100 mg of caffeine.
- National Coffee Association of U.S.A., Inc.; 2011 National Coffee drinking Trends Study
- "USAToday"; Tea is Steeped in Health Benefits; October 2007
- Lakartidningen; Is Caffeine Addictive?; JW Daly; December 1998
- "Annals of the Rheumatic Diseases"; Coffee Consumption, Rheumatoid Factor, and the Risk of Rheumatoid Arthritis; 2000
- “Annals of Rheumatoid Diseases”; Day and Night Pain Measurement in Rheumatoid Arthritis; B. Rojkovich; July 1998
- National Institute of Neurological Disorders and Stroke; Restless Legs Syndrome Fact Sheet; September 2010