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The Right (and Wrong) Uses of Caffeine

Coffee pouring into cup with coffee beans scattered in the background.


In this Article:

  • Caffeine can be found in foods, beverages, supplements, medicine, and energy drinks.
  • Caffeine can boost your performance at times, but it can also be bad for your health.
  • You can safely consume up to 400mg of caffeine each day.

Can’t make it through the morning without a caffeine kick? Need a boost before PT? You are not alone. More than 80% of adults in the U.S. drink caffeine every day. Caffeine may seem like an easy energy fix, but too much can be bad for your health.

What Is Caffeine?

Caffeine is a stimulant that gives most people an energy boost. Your body quickly absorbs caffeine and uses it for a few hours, and then you pee it out.

It’s naturally made in plants such as tea leaves, coffee beans, cacao beans, guarana, and green tea extract. But caffeine can also be produced in a lab.

Caffeine is in many foods and drinks:

  • Energy drinks—160mg per 16-ounce can
  • Coffee—100mg per 8-ounce cup
  • Dark chocolate—70mg per bar
  • Espresso—60mg per shot
  • Soda—50mg per 12-ounce can
  • Tea—50mg per 8-ounce cup

(Note: Caffeine amounts listed above are average and can vary by brand.)

Some over-the-counter drugs, dietary supplements, and cold medicines have caffeine too, so be sure to check the label so you know what you are taking.

What Are the Pros and Cons of Caffeine?

Moderate amounts of caffeine (about 200 mg) can boost your mental and physical performance while on a mission, working a night shift, or training for the APFT. Some benefits of caffeine include helping to:

  • Keep you awake
  • Make you more alert
  • Give you better concentration
  • Boost your energy

How your body reacts to caffeine depends on your metabolism and how much caffeine you consume. The side effects of caffeine vary, but regularly consuming large amounts daily can lead to:

  • Upset stomach or heartburn
  • Changes in sleep patterns
  • Insomnia
  • Body tremors
  • Increase in heart rate and blood pressure
  • Anxiety
  • Blocked calcium absorption
  • Chest pains
  • Dehydration
  • A toxic reaction when mixed with other stimulants

If you want to scale back on caffeine, gradually reduce the amount you have each day to prevent headaches, irritability, and mood swings.

How Much Caffeine Can I Have?

Adults can safely consume up to 400mg of caffeine a day, but experts recommend eating or drinking only 200mg or less at a time. A cup of coffee before you hit the gym is fine. Just wait for a couple of hours before you have any more caffeine.

Try to stay away from caffeine in the evening within four hours of bedtime to keep from disrupting your sleep pattern. This is especially important when you need to be well rested for drill weekend or the day of your APFT.

The key to staying safe and healthy is to stay below 800mg of caffeine a day. The Food and Drug Administration warns that although caffeine affects people in different ways, too much at once can be fatal.

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