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Dangerous Side Effects of Drinking Decaf Coffee, According to Science

You won't believe what's in your cup...
FACT CHECKED BY Kiersten Hickman

Decaffeinated coffee is touted as a coffee replacement in a variety of health arenas. Insomniacs applaud its lack of caffeine: drink decaf instead of cup number three, they say, and put sleep trouble to bed. Dentists commend the low acidity levels—a decaf pour causes less tooth damage than its traditional sister. And the beverage is even recommended to pregnant women who have been warned to watch their caffeine intake. But what if we told you that decaf cup of coffee actually has a myriad of dangerous side effects you didn't know about?

With such a range of people who are pro-decaf, it's hard to imagine that the coffee alternative could be dangerous. However, after speaking with several dietitians and doctors, we've uncovered an assortment of dangerous side effects that are brewing in the decaf coffee world. Here they are, and for more healthy tips, be sure to check out our list of The 7 Healthiest Foods to Eat Right Now.

You could be ingesting dangerous chemicals.

Cup of decaf coffee

Coffee beans naturally contain caffeine, so removing the stimulant is difficult and often done in unnatural ways.

"The beans are soaked in a chemical solvent that leaches out the caffeine," says Dr. William Li, physician, scientist, president and medical director of the Angiogenesis Foundation, and author of Eat To Beat Disease: The New Science of How Your Body Can Heal Itself. "Some of the solvents are the same ones used in paint thinner or nail polish remover."

Although the FDA has approved these chemicals (namely, methylene chloride) in the decaffeination process, they still present a host of health risks.

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These chemicals can cause major health issues.

Man barista making coffee latte

Methylene chloride is not a mild chemical. Dr. Rashimi Byakodi points to the way inhalation exposure irritates the nose, throat, and affects the nervous system.

"It's believed to temporarily slow down our central nervous system," says Dr. Ava Williams.

Perhaps most frighteningly, Dr. Byakodi says, "Methylene chloride is a possible mutagen and is reasonably anticipated to be a human carcinogen."

Chemicals aside, even just the process of decaffeination can be problematic. "Some studies have shown a potential risk for triggering rheumatoid arthritis," says Dr. Olivia Audrey.

Dr. Williams adds that the process has been found to increase fatty acids that can affect metabolic syndrome and increase the risk of heart disease.

These chemicals can affect your nervous system, cause rheumatoid arthritis, and even present a cancer risk.

Maybe it's time to drink the real thing! Here are 15 Coffee Facts You Never Knew.

Decaf coffee can raise your cholesterol.

Iced coffee

Turns out, the decaffeination process and the chemicals used in it aren't even the beginning of the story. The risks of decaf start even earlier—with the bean selection itself.

Decaf coffee, "is that typically it is made from a bean that has a higher fat content than regular arabica beans, which could pose potential consequences for cholesterol levels and long-term health of the heart as well," says Dr. Audrey.

Dr. Williams continues to explain that a commonly used bean for decaf coffee is Robusta, which "has higher diptenes, [which are] fats that stimulate fatty acid production in the body."

Here are the 17 Foods That Lower Cholesterol.

You're not getting the same health benefits as regular coffee.


Nutritionist Ella Davar, RD, CDN, says it best: the decaffeination process "makes the decaf coffee an ultra-processed food item." So, although coffee is fairly natural, its decaffeinated counterpart is the opposite.

Besides the obvious benefits of ingesting a natural substance over an unnatural one, regular coffee has health benefits that decaf coffee is missing.

Dr. Li points to "many of the natural bioactive chemicals that boost your health defenses," which are lost in decaffeination. One of them in particular, chlorogenic acid, "can activate your immunity and even slow cellular aging," he says.

Dr. Ceppie Merry, FRCPI, PhD, adds that there is some evidence suggesting that the beans used for decaf coffee do not offer the same cardioprotective effects like the ones used in caffeinated coffee.

You're still getting the health drawbacks.

cup of coffee

Dr. Li points to the fact that decaf coffee does still have some caffeine in it—usually about 5%, although that amount is largely unregulated. "Just remember," he says, "it is decaffeinated, not no-caffeination."

Basically, if you're trying to quit caffeine for health reasons, decaf won't necessarily do the trick.

And, although decaf coffee is less acidic, registered dietitian Noman Imam, Ph.D., explains that it can still increase serum gastrin concentrations, which triggers acidity.

In a nutshell, the health risks of caffeinated coffee remain consistent with decaffeinated coffee. Dr. Byakodi cites a comparative study that revealed just that, concluding that "shifting from caffeinated to decaffeinated coffee is unjustified."

So instead, brew yourself a cup of joe and try making one of these 12 Tastiest Homemade Coffee Drinks From a Nutritionist.

Kaley Roberts
Kaley Roberts is a food writer. Read more about Kaley
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