Facts on Caffeine

steaming cup of coffee surrounded by coffee beans

Caffeine is a natural ingredient found in coffee beans, tea leaves, cocoa beans, guarana and yerba maté. It is added to some carbonated drinks and cold and headache medications.

Caffeine and your body

Caffeine acts as a stimulant (increases alertness). Some people are more sensitive to caffeine than others. For these people, too much caffeine can cause:

  • trouble sleeping
  • irritability
  • nervousness
  • rapid heart rate
  • headaches

Safe amounts of caffeine

The following amounts of caffeine are considered safe:


Milligrams per day (mg/day)

Men and women, 19 and older


Pregnant and breastfeeding women 19 and older   


Caffeine and children

Children under 12 years old should not have more than 2.5 milligrams of caffeine per kilogram of body weight.


Milligrams per day (mg/day)

Children, aged 4 to 6

45 (about one 355mL can of cola)

Children, aged 7 to 9

62 (about one and a half 355mL cans of cola)

Children, aged 10 to 12

85 (nearly two 355mL cans of cola)

Caffeine and teenagers

Adolescents 13 years old and older should not have more than 2.5 milligrams of caffeine per kilogram of body weight.

Common sources of caffeine

Caffeine in coffee or coffee based beverages 


Serving Size

Caffeine (mg)

Coffee, brewed

250mL (1 cup or 8 oz)

80 – 179

Cappuccino or Latte

250mL (1 cup or 8 oz)

45 – 148

Coffee, instant

250mL (1 cup or 8 oz)

81 – 106

Espresso, brewed

30mL (1 oz)

64 – 90

Decaffeinated coffee/span

250mL (1 cup or 8 oz)/span

3 – 15

Caffeine in tea 


Serving Size

Caffeine (mg)

Iced tea, sweetened

1 can (355 mL)

22 – 64

Tea, leaf or bag (black, flavoured black)

250mL (1 cup)

43 – 50

Tea (green, oolong, white)

250mL (1 cup)

25 – 45

Decaffeinated tea

250mL (1 cup)

0 – 5

Herbal teas, all varieties

250mL (1 cup)


Caffeine in other beverages


Serving Size

Caffeine (mg)

Energy drink, various types

250mL (1cup)

80 – 97

Diet cola

355 mL (1 can)

25 – 50


355 mL (1 can)

37 – 38

Learn more about energy drinks by reading Energy Drinks FAQs.

Moderation is key

It is important to know what your children are drinking. Offer a beverage that has little or no caffeine. Choose beverages such as:

  • Water
  • 100% fruit juice
  • Milk, chocolate milk or hot chocolate 

If you think you may be taking in too much caffeine, the best approach is to limit your caffeine intake gradually over several days.

Tips on lowering your caffeine intake:

  • Enjoy refreshing water
  • Try flavoured herbal tea over ice. Some herbal teas need to be avoided during pregnancy and breastfeeding. 
  • Instead of 3 cups of coffee a day, cut down gradually by having 2 cups of coffee and 1 cup of decaffeinated coffee.

Last Update – April 26, 2018

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