Caffeine and Your Colon

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The debate around the effect of caffeine on your colon rages on, with research divided as to whether or not caffeine is good or bad. Drinking coffee -- not the coffee enemas that are unfortunately gaining a following -- has demonstrated a decreased risk of colon cancer in some studies, and an increased risk in others. Although there is no definitive proof either way, these studies have shed some light on the potential effects of caffeine.


Caffeine is a Drug

Caffeine is an alkaloid drug; a chemical compound found naturally in cocoa, coffee beans, and many over the counter stimulant type drugs. It is also addictive, which means your body starts to crave the physiological effects it provides. Ever try to go a day or two without your morning cup of joe? Caffeine has multiple effects on your body, some of which you probably know and have experienced. The increased need to urinate after coffee consumption is directly related to the diuretic -- water removing -- effect it has. The other well-known effect of caffeine is the fact that it is a stimulant, directly affecting your central nervous system.  

What the Research Shows

The first decade of this century boasted many small studies showing a decreased incidence of colorectal cancers in people who consistently drank coffee. Along with the java boom, where you couldn't toss a coin in the U.S.

without hitting a coffee shop, this was perceived as good news. 

More recent studies remain not only remain divided on whether or not coffee is beneficial to your colon, but some actually report that excess coffee consumption -- four or more cups daily -- can actually increase colon cancer risk in certain populations.

One such study in Japan of over 55,000 participants showed that increased coffee consumption in men increased the risk of developing colon cancer. There was no instance of an increased risk in women who drank coffee, nor was there any correlation to coffee consumption and rectal cancer.

Another large meta analysis in Europe reflected a decreased occurrence of colon cancer in women who drank coffee daily. The effects on men were inconclusive -- again adding to the dissent.

Keep It Safe

Until a final conclusion to this controversy is found, it is wise to keep caffeine consumption in moderation. The United States Food and Drug Administration encourages not exceeding 400 milligrams of caffeine daily for the average healthy adult. This equates to about four or five regular cups of coffee. You might also want to track your overall intake of caffeine, as it isn't only found in java. Chocolate, tea, diet pills, weight loss shakes, stimulants, and even some over-the-counter headache relief medications contain a large amount of caffeine.

When in doubt, read the label and don't exceed the 400 milligram mark daily. 

Too Much of Anything is Bad

Almost anything, if not used in moderation, has potential side effects. Caffeine is no different. If you've ever had one too many cups of coffee and felt jittery, irritable, and restless, you probably felt those side effects first hand. You can have too much caffeine -- it's called caffeine toxicity and although death by caffeine is rare, it is possible. The symptoms of caffeine toxicity include:

  • Confusion
  • Convulsions
  • Dizziness
  • Fever
  • Irritability
  • Hallucinations
  • Irregular heart beat or elevated heart rate

If you or a loved one suspects caffeine toxicity or overdose, seek emergency medical assistance by dialing your local emergency medical system (such as 911) or the National Poison Control Center at 1-800-222-1222.


Li, G. et al. (2013).Coffee Consumption and Risk of Colorectal Cancer: A Meta-analysis of Observational Studies.Public Health Nutrition. Accessed online July 27, 2015.

United States Food and Drug Administration. (n.d.). FDA to Investigate Added Caffeine. Accessed online July 28, 2015.

Yamada, J. et al. (2014). Coffee Consumption and Risk of Colorectal Cancer. Journal of Epidemiology. Accessed online July 22, 2015.

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