5 Side Effects of Too Much Caffeine

If you’re like nearly 80 percent of adults, your day doesn't start until you've had a little caffeine.  Whether you get it from coffee, soda, or tea you probably look to caffeine to jump start your morning and help you become alert, energized, and focused.

That’s not a bad thing for most people.  At least not until a little caffeine becomes a lot. If your overall health is good and you don’t have any other health conditions, the most common signs you’re having too much caffeine include you:

  1. Have trouble sleeping (Did you know that half of the caffeine you get at 10 A.M. can still be with you at 10 P.M.?)
  2. Feel nervous, restless, or irritable
  3. Are having stomach problems or heart burn
  4. Experience dizziness or feel shaky
  5. Notice your heart racing or beating unevenly

Caffeine is also a diuretic and it can lead to dehydration – you might not notice you’re dehydrated right away either. When you drink caffeinated products it’s important to make sure you’re also drinking a lot of water.

How Much Caffeine is Safe Per Day

Most recommendations say that 200 milligrams (mg) of caffeine is safe for most adults to have per day. Kids caffeine intake should be very limited, if any at all.

An example of 200 mg of caffeine is:

  • Approximately two 5-ounce cups of coffee,
  • Approximately four 12-ounce cans of Mountain Dew, or
  • Approximately  four 5-ounce cups of tea

Up to 400 mg of caffeine is okay for some people. But once you pass that, it can be trouble.  Most experts agree that 600 mg (four to seven cups of coffee) is a real danger zone.  That’s 5-ounce cups, not the mega-mug you probably have at home or at your desk.

The important thing with caffeine is to listen to your body. Some people are really sensitive to caffeine.  Although there are consumption recommendations, you can have problems at much lower doses of this “over-the-kitchen-counter” drug.

If you’re interested in learning about caffeine content in common foods and drinks, read this article from the FDA.

When to Be Careful with Caffeine

If you have health problems or take medications, pay extra attention to how much caffeine you’re having. It can make medical conditions like heart problems, diabetes, osteoporosis, and others worse when it:

  • Makes the heart work harder and raises your blood pressure
  • Aggravates panic attacks
  • Raises blood sugar levels (especially in soda or when sugar is added to coffee and tea)
  • Gets in the way of calcium absorption and can lead to spinal bone loss
  • Increases acidity, irritates the gut, reduces iron absorption

Caffeine can also get in the way of some medications and dietary supplements. It’s a good idea to check with your doctor or pharmacist about caffeine if you have health issues or take medication.

Tips to Limit, or Eliminate Caffeine

Caffeine is a natural product and a drug. It’s a mixed bag of good and not-so-good. It’s addictive, so changing your habits can be a struggle.

The best way to reduce your caffeine consumption depends on you:

  • If you quit cold-turkey:
    • Expect headaches, fatigue, and other unpleasantness. (They’ll go away after a few days)
  • If you do it gradually:
    • Start with one less caffeinated drink a day
    • Stop drinking caffeine at noon (this will probably help you sleep better too)
    • Switch to decaf and you won’t notice the change as much
    • Replace coffee with a healthier alternative like water, green or black tea (it has half as much caffeine and it’s both energizing and relaxing), or herbal tea

Final Thoughts

Remember that caffeine is a drug. While it’s generally safe for most people to consume in small doses, it’s addictive and can be difficult to cut back or stop altogether. If it starts to make you feel bad, don’t underestimate what you’re feeling. Too much caffeine can be very dangerous.

If you have health conditions or take medication, talk to your doctor or pharmacist to determine if caffeine is safe for you. Cutting out or limiting caffeine can be a great thing. After you get past the withdrawal, you may feel less anxious or irritable, have less muscle tension or indigestion, be more focused, and have extra money in your pocket. And because you’ll be sleeping better, you’ll be more alert and energetic.

Meet the Author

Heather Klug, MEd RD is a registered dietitian and cardiac educator at the Karen Yontz Women's Cardiac Awareness Center inside Aurora St. Luke's Medical Center in Milwaukee, WI.

Read more posts from this author

The information presented in this site is intended for general information and educational purposes. It is not intended to replace the advice of your own physician. Contact your physician if you believe you have a health problem.

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