Download PDF (174k) - Page will open in a new window Email to a Friend

The Buzz About Caffeine

Have you ever wondered whether you're a true caffeine "addict"? If any of the following accurately describes you, you may want to consider yourself hooked:

  • You can skip your morning shower or even breakfast...but not your triple espresso.
  • You're standing in line to buy your beloved tea and realize you forgot your wallet...and you seriously consider offering to do some dishes or wipe a few tables as a trade-off.
  • Your idea of a nutritious breakfast is diet soda.

Don't worry - you're not alone. Every day, millions of people use caffeine to get up and running...or get over the mid-day hump...or stay awake through a late-night movie marathon... or just because. In fact, people have been enjoying foods and beverages containing caffeine for thousands of years.

Most experts agree that moderate amounts of caffeine won't harm you - and in some cases, it can even have positive effects. But whether you're a-cup-a-day social coffee drinker or six-pack-aday soda addict, it's important to understand what caffeine really does for you...and to you.

Caffeine culprits

According to the International Food Information Council (IFIC), caffeine is a naturally occurring substance found in the leaves, seeds, or fruits of more than 60 plants.

The following chart from the IFIC provides a quick breakdown of some of the most widely consumed sources of caffeine.

In addition, you probably have drugs in your medicine cabinet that contain caffeine - even if you don't know it. Certain pain relievers and products to help you stay awake list caffeine as an ingredient - as much as 200 mg in a standard dosage.

The physical effects of caffeine

You probably know firsthand the effects of caffeine - and what happens when you don't get it.

Caffeine acts as a stimulant by exerting a strong effect on the central nervous system. Its effects on the body may begin as early as 15 minutes and last up to six hours. According to University Health Service at the University of Michigan, caffeine may increase body temperature, blood fl ow to the skin and extremities, blood pressure, blood sugar levels, stomach acid secretion, and urine production (diuretic).

Caffeine may increase alertness in tired individuals and enhance performance of certain tasks. Many people find caffeinated beverages help them stay alert when they work or study. They report feeling less fatigued, their thoughts fl ow easily, they are better able to pay attention, and motor activity seems to increase.

On the down side...Caffeine can have negative effects on the body, which is why some doctors and researchers suggest you limit your intake. People who are especially sensitive to caffeine sometimes notice side effects including:

  • Insomnia
  • Restlessness
  • Irritability
  • Nervousness
  • Headaches
  • Hand tremors
  • Irregular heartbeat
  • Difficulty concentrating

  • The University of Michigan reports that too much caffeine may lead to sleep deprivation and a tendency to disregard normal warning signals that the body is tired and needs rest. Caffeine does not replenish energy or prevent emotional fatigue; food and sleep are the only remedies for these. When normal sleeping patterns are continually disrupted, you may begin to feel depressed. Too much caffeine may also lead to anxiety-related feelings such as excessive nervousness, sweating, and tremors.

    People who are taking medications for depression, anxiety or insomnia, high blood pressure, other heart problems, chronic stomach upset, or kidney disease should avoid caffeine until discussing it with their doctor.

    Moderation is key

    You've heard it over and over...there is little harm in moderate amounts of caffeine. But how do you know what's considered "moderate"... and more importantly, moderate for you?

    According to both the IFIC and the American Dietetic Association (ADA),3 moderate caffeine consumption is considered to be 200-300 mg per day. This is the approximate equivalent of:

  • Two to three cups of coffee
  • Four to fi ve 12-oz. soft drinks

  • Again, this depends on your sensitivity to caffeine and can vary from one to several beverages.

    A word on soft drinks...

    Soft drinks are not only a source of caffeine, but regular sodas are a major source of excess - and empty - calories, as well as added sugars. Whenever possible, choose diet soft drinks. Or better yet - go for water or non-fat/low-fat milk.

    If you're pregnant...

    The U.S. Food and Drug Administration (FDA) - as well as many doctors - encourage pregnant women to consume caffeine in moderation, and some recommend you hold off completely until after your baby arrives.

    It is important to consult with your doctor about caffeine use during pregnancy.

    Kicking the habit

    Maybe you've decided to start making healthy lifestyle changes. Or maybe you're looking to save some money. You'll see immediate results simply by cutting back on the number of caffeinated beverages you buy in a day. But how do you do it? Drink plenty of water. Get enough sleep. Eat a healthy, balanced diet. Get your energy boost from exercise instead of caffeine.

    You don't have to go "cold turkey."

    If you decide to cut down on the amount of caffeine you consume - or even cut it out of your diet completely - it's better to do it gradually. Withdrawal symptoms usually taper off within 48 hours and are gone within a week or so - and cutting down gradually may help reduce or eliminate those symptoms. For example, gradually reduce the number of cups of coffee you drink per day - even if it's only by half a cup at fi rst. Or brew mixtures of caffeinated and decaffeinated coffee. Continue weeding it out of your daily diet until you've reached your goal. Be aware of other caffeine containing beverages, foods, and medications that will counteract your efforts.



    Typical Range*
    In milligrams (mg)


    Coffees (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


    Other beverages


    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

    *Due to brewing method, plant variety, brand, etc.



    Talk to your doctor about caffeine. He or she will be able to provide you with important information about how much you should be consuming – and how often.

      1. Everything You Need to Know About Caffeine.International Food Information Council (IFIC). July 1998. Updated 21 July 2003.
      2. Caffeine.University of Michigan. University Health Service. Updated 2004.

    Centers for Disease Control and Prevention (CDC). U.S. Department of Health and Human Services. May 27, 2004. Viewed online 03/12/2007.

    1. Caffeine & Coffee: Are There Health Risks? American Dietetic Association. 10 June 2004.