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Caffeine
1 . It's 11:00 P.M. and you've already had a full day of work or school. You're tired and you know you could use some sleep. But you still haven't finished everything you need to do or watched the movie that's due back tomorrow. So instead of going to bed, you reach for the remote-and the caffeine.
2 . What Is Caffeine?
Caffeine is a drug that is naturally produced in the leaves and seeds of many plants. It's also produced artificially and added to certain foods. Caffeine is part of the same group of drugs sometimes used to treat asthma.
3 . It is estimated that around the world people consume 120,000 tons of caffeine annually. Look at it another way. Every one of the 5 million people on the earth drinks one beverage-one cup-containing caffeine a day. Tea is the caffeinated beverage of choice.
4 . Caffeine is defined as a drug because it stimulates the central nervous system., the brain and spinal cord. Caffeine causes the heart to beat faster and makes a person feel wide awake. Most people who are sensitive to caffeine experience a temporary increase in energy. And they feel happier.
5 . Caffeine is in tea leaves, coffee beans, chocolate, many soft drinks, and pain relievers. In its natural form, caffeine tastes very bitter. This is why most caffeinated drinks go through processing to hide the bitter taste.
6 . Got the Jitters?
The amount of caffeine in different beverages varies greatly. Many sodas have added caffeine. A 12-ounce cola can have between 38 mg and 71.2 milligrams (mg) of caffeine. A 5-ounce cup of brewed coffee, on average, contains 115 mg of caffeine. Iced tea (12 ounces) contains 70 mg. Dark chocolate has approximately 20 mg per ounce. Milk chocolate contains much less: 6 mg.
7 . If people take it in moderate amounts (a single can of soda or cup of coffee), caffeine increases their ability to think quickly and clearly. Higher doses of caffeine (several cups of coffee) can cause anxiety, dizziness, headaches, and the jitters. Caffeine can make it difficult to sleep.
8 . Caffeine is addictive and may cause withdrawal symptoms for those who suddenly stop consuming it. These include severe headaches, muscle aches, temporary depression, and irritability.
9 . Caffeine moves through body within a few hours after it's consumed and then passes through the urine. It's not stored in the body, but you may feel it's effect for up to six hours if you're sensitive to it.
10 . Moderation Is the Key
Effects of caffeine vary from one person to the next. However, doctors recommend that people should consume no more than about 100 milligrams of caffeine daily. That might sound like a lot, but one espresso contains about 100 milligrams of caffeine!