How Much Tea or Coffee is OK in a Day?

Do not drink more than eight cups (150 mL) of coffee or twenty(!) cups of tea a day.

Caffeine Contents of Beverages

• A 150 mL cup of tea contains 20 mg of caffeine.
• A 150 mL cup of coffee contains between 35 and 100 mg caffeine based on the brewing method and reduces if milk is added. In a 150 mL cup with no milk added:
  • Instant coffee will have 35 mg of caffeine;
  • Brewed coffee has 50 mg of caffeine;
  • Cold-brewed coffee has 100 mg of caffeine; and
  • Espresso coffee will have 320 mg of caffeine (though remember that a typical espresso shot is 30 mL, and not 150 mL).
• The Western world uses a 235 mL cup (and a 300 mL mug), while a 150 mL cup is more prevalent in India. In this article, a cup refers to the Indian size.
• A 250 mL glass of most soft drinks (aerated drinks or soda, as they are called in the U.S.A.) has 50 mg of caffeine.
• No one drinks soft drinks in a small teacup. So just for comparison, aerated drinks have 30 mg of caffeine compared to 20 mg in tea and 50 mg in coffee per 150 mL.
• Even non-cola drinks such as orange- and lemon-flavoured aerated drinks can have similar caffeine amounts.
• Some energy drinks are spiked with caffeine. Be very careful when drinking them.
• Decaffeinated drinks have less caffeine than regular ones, but not zero caffeine. Check the label.

Caffeine Consumption Guidelines

Guidelines for General Public

• US Food and Drug Administration (FDA) advises against consuming more than 400 mg of caffeine daily.
• Exceeding 1,200 mg of caffeine a day can trigger epileptic seizures. While it is unlikely that one can drink enough regular beverages to hit this limit, energy drinks spiked with caffeine can lead to this overdose.

Guidelines for High BP Patients

• People with high blood pressure (more than 160/100 mmHg) should avoid more than three cups (total 500 mL) of coffee a day, as it increases their risk of getting a heart attack and stroke.

Guidelines for Osteoporosis Patients

A 100 mg of caffeine causes 6 mg of calcium loss, while most of our diets are deficient in calcium by 250 to 500 mg daily. So if you have fragile bones, do not exceed 200 mg of caffeine a day.

Guidelines for Pregnant and Nursing Women

• The American College of Obstetricians and Gynecologists (ACOG) advises pregnant women to consume less than 200 mg of caffeine daily.
• Nursing mothers or pregnant women should avoid more than four cups of coffee daily.
• Newborns and preterm infants are especially more sensitive to caffeine.

Guidelines for Children and Adolescents

• The US FDA has no guidelines for caffeine consumption in children.
• The American Academy of Pediatrics (AAP) recommends that children below 12 years should not consume any caffeine. If you have kids, you know that this will never work given our all-pervasive aerated drink culture.
• Do not exceed 100 mg of caffeine in healthy adolescents (12 to 18 years) a day.
• Studies show that caffeine’s toxic effects are seen in kids below 12 years above 2.5 mg per kg of their body weight a day.

To Read More

• U.S. Food & Drug Administration: Spilling the Beans: How Much Caffeine is Too Much?
• Health.com: How To Know if Your Coffee Habit Is Too Much Caffeine
• On this Website: How Coffee Can Make You More Tired
• On this Website: Is Coffee Bad For High Blood Pressure Patients?

First Published on: 25th April 2023
Image Credit: Image by Freepik
Last Updated on: 19th July 2023