How much do you know about caffeine?


When BBC Scotland's Kenneth Macdonald set out to discover what caffeine was doing to his brain he unearthed some startling facts. Do you know what caffeine is doing to your body each day? Try our eight-question quiz.

Ken Macdonald

1.) Multiple Choice Question

What is the "official" name of the chemical stimulant caffeine?

Lab tests
  1. Trimethylxanthine
  2. Adenosine
  3. Tryptamine

2.) Multiple Choice Question

What colour is caffeine?

  1. Brown
  2. Red
  3. White

3.) Multiple Choice Question

What does caffeine do for plants?

Plants growing
  1. It kills them
  2. It kills insects
  3. It helps them grow

4.) Multiple Choice Question

What is the recommended daily limit of caffeine intake for pregnant women?

Preganant woman
  1. Four cups of coffee
  2. One cup of coffee
  3. Two cups of coffee

5.) Multiple Choice Question

Which has more caffeine, milk chocolate or dark chocolate?

  1. Milk chocolate
  2. Dark chocolate

6.) Multiple Choice Question

What has the highest level of caffeine - tea, Coke or Diet Coke?

composite pics
  1. Tea
  2. Coke
  3. Diet Coke

7.) Multiple Choice Question

What has the most caffeine content - Single Starbucks Espresso; Grande Starbucks Latte or a Red Bull?

Coffee and Red Bull
  1. Single Starbucks Espresso
  2. Grande Starbucks Latte
  3. Red Bull

8.) Multiple Choice Question

What level of milligrams of caffeine per litre triggers the need for labelling a product high in caffeine?

Fizzy drinks
  1. 150mg
  2. 175mg
  3. 155mg


  1. Caffeine is a naturally occurring chemical stimulant called trimethylxanthine. Its chemical formula is C8H10N4O2 and it is a psychoactive drug, like cocaine.
  2. Although most caffeinated drinks have a dark colour, caffeine is a white, bitter-tasting, crystalline substance.
  3. Caffeine is found in many plant species, where it acts as a natural pesticide. It paralyses and kills certain insects feeding on the plant.
  4. The Food Standards Agency says pregnant women are advised not to have more than 200mg of caffeine a day, roughly two mugs of instant coffee.
  5. Dark chocolate has more caffeine. A typical 40 grams of dark chocolate contains 23mg of caffeine compared with a typical 40 grams of milk chocolate containing 6mg of caffeine.
  6. A typical cup of tea contains 40mg of caffeine; a Diet Coke contains 42mg of caffeine and a Coke contains 32mg of caffeine. So, if you want to reduce your caffeine levels, keep off the Diet Coke!
  7. Grande Starbucks Latte contains 150mg of caffeine; a single Starbucks Espresso contains 75mg of caffeine and a Red Bull can has 80mg of caffeine. The British Soft Drinks Association says children under 16 should not be consuming drinks with high caffeine content.
  8. Drinks containing more than 150mg of caffeine per litre (mg/l) must be labelled with the term "high caffeine content" in the same field of vision as the product name. However, the labelling does not apply to coffee and tea drinks.

Your Score

0 - 3 : Need a stimulant

4 - 6 : Chocolate reward

7 - 8 : Double espresso