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Health Education

Alcohol, Tobacco, and Other Drugs

What is caffeine?

Caffeine is a legal central nervous system stimulant naturally occurring in coffee, tea, chocolate, and other products. It is also artificially added to products like soda or energy drinks. Caffeine is believed to be the most popular drug in the world, consumed by up to 90% of people.

What are the effects of caffeine?

The effects of caffeine vary based on an individual's sensitivity to the drug. The concentration of the drug in the body peaks within one hour of consuming caffeine, and its effects can last from 4 to 6 hours. Most people experience enhanced mental alertness after ingesting caffeine; therefore, college students often consume caffeine to aid them in studying.

In addition to increasing mental alertness, caffeine, as is the case with other stimulants, raises the heart rate and blood pressure; but experts agree that consumption is safe for most people in moderation (less than 300mg per day).

In larger quantities (which differs for each individual), caffeine can cause additional detrimental effects on your body, including:

  1. Diuretic effects. Caffeine intake increases urination and water loss from the body which can lead to dehydration.
  2. Feelings of anxiety, panic, restlessness, or "the jitters."
  3. Difficulty sleeping, especially if you consume caffeine late at night.
  4. Headaches.
  5. Pregnancy concerns, such as miscarriage, preterm delivery, and low-birth weight. Though conflicting evidence exists about these effects of caffeine, the CDC, FDA, and March of Dimes recommend that pregnant women limit their caffeine intake as a precaution.
How much caffeine am I consuming?

The following chart displays the caffeine content of some beverages and foods that contain caffeine. Many other products contain caffeine (even chocolate!), so it is important to read nutrition labels to keep track of how much you’re consuming.

What products contain caffeine and how much?*

Milligrams of Caffeine
Items Typical Range**
Coffee (8-oz. cup)    
Brewed, drip method 85 65-120
Instant 75 60-85
Decaffeinated 3 2-4
Espresso (1 oz. cup) 40 30-50
Teas (8-oz. cup)    
Brewed, major U.S. brands 40 20-90
Brewed, imported brands 60 25-110
Instant 28 24-31
Iced (8-oz. glass) 25 9-50
Some soft drinks (8 oz.) 24 20-40
Cocoa beverage (8 oz.) 6 3-32
Chocolate milk beverage (8 oz.) 5 2-7
Milk chocolate (1 oz.) 6 1-15
Dark chocolate, semi-sweet (1 oz.) 20 5-35
Baker's chocolate (1 oz.) 26 26
Chocolate-flavored syrup (1 oz.) 4 4

* Source: International Food Information Council
**Due to brewing method, plant variety, brand, etc.

Is caffeine addictive?

Caffeine has addictive properties. When individuals who regularly consume caffeine abruptly stop, they can experience withdrawal symptoms such as headaches, fatigue, irritability, and nausea or vomiting.

What are some tips for cutting down on caffeine intake?
  1. Balance drinking caffeinated beverages with non-caffeinated beverages. For example, if you drink a cup of coffee to get you going in the morning, the next thing you drink should be water.
  2. If you feel thirsty, do not reach for a caffeinated drink—the diuretic effects of the caffeine will leave you feeling thirstier.
  3. Set a deadline for caffeine consumption. For example, plan to drink no caffeine after 4:00 p.m. every day.
  4. Do not drink caffeinated drinks mixed with alcohol. Both caffeine and alcohol can lead to dehydration.
  5. Avoid energy drinks which have more caffeine than regular sodas.
  6. Get plenty of rest so that your body will not feel as tired and you will not be tempted to drink caffeinated beverages.
  7. If you are studying and need a pick-me-up, rather than reaching for coffee, go for a quick walk.
  8. Do not take caffeine pills like No Doz.