For years, caffeine has been the "drug" of choice in many cultures. Caffeine has been considered socially acceptable because it is found in drinks like tea or coffee. People who consume a lot of caffeine-based drinks may think they are addicted -- depending heavily on the substance. But if they stop using such drinks, they will experience only mild symptoms of withdrawal for a few days.

The real addiction may be emotional. Many people claim they cannot start their day unless they get their "fix," which is, in many cases, a cup or two of coffee. Some people drink coffee throughout the day. Even young people who may not touch tea or coffee are still putting caffeine into their bodies when they have energy drinks, which have high amounts of caffeine.

Caffeine is a bitter substance found in coffee, tea, soft drinks, chocolate, kola nuts, and some medicines. It has many effects on the body, including helping to activate the central nervous system. This can make you more awake and give you increased energy.

America`s National Institutes of Health says drinking two to four cups of coffee a day is not harmful for most people. But it warns that too much caffeine can make you restless, irritable and worried. It may also cause headaches, abnormal heartbeats and other problems. The NIH says women who are pregnant or breast-feeding should limit their consumption of caffeine. And it says caffeine may affect how the body reacts to some drugs and vitamins. It suggests talking with a doctor if you have questions.

Would you like a drink of coffee or tea? A mathematical study showed that tea -- especially black tea -- might be the best choice. The study showed that few people have Type 2 diabetes in countries where people drink a lot of tea. Diabetes is a life-threatening condition that reduces the ability of the body to turn glucose -- or sugar -- into energy. It is a growing problem around the world. The number of people with diabetes is expected to rise sharply, to 438 million, over the next 20 years.

A team of researchers studied the amount of black tea sold in 50 countries. It compared the sales records with information from the World Health Organization about diseases in those nations. People in Ireland were the top tea-drinkers. On average, each person there drank more than two kilograms of black tea a year. People in China, Morocco and Mexico drank the least tea.

The study showed a link between black tea sales and rates of diabetes, but not with any other health condition. Organizers of the study say the link does not necessarily prove that black tea prevents diabetes. But they say earlier research had suggested that some parts of black tea have a possible link to good health. People have been drinking tea for many centuries. It is one of the world`s most widely-consumed hot drinks.