Caffeine

What is caffeine?

Caffeine is a chemical found in foods and drinks. It can stimulate your brain and nervous system.

It is found in:

• coffee
• tea leaves
• cocoa beans
• guarana — a South American plant with high levels of natural caffeine
• chocolate
• cola drinks
• energy drinks

Caffeine and medicines

Caffeine can also be found in some prescription and over-the-counter medicines, such as some:

• pain-relief medicines
• cough medicines
• weight loss products

How will caffeine affect my body?

Caffeine affects everyone differently.

The effect of caffeine depends on:

• your height, weight and general health
• the amount you eat or drink
• genetic factors
• whether you regularly eat or drink caffeine
• whether other food or drugs (including alcohol) are taken at the same time
• your mood

Caffeine stays active for longer in the bodies of:

• babies
• pregnant women
• older people

People with existing medical conditions, such as high blood pressure, may be more sensitive to caffeine. This can make a normal amount of caffeine more dangerous. If you have an existing medical condition, it’s a good idea to eat or drink less caffeine.

It’s not always clear how your body will respond to caffeine. Much of the medical research in this area has been into coffee, which contains caffeine and many other ingredients.

How much caffeine does it contain?

The amount of caffeine in food and drinks varies. For example, an espresso has more caffeine than instant coffee. Similarly, dark chocolate has more caffeine than milk chocolate.