May 03, 2018 5 min read

Is Decaf Coffee Bad for You?

How Caffeine is Stripped from Coffee

In the early 1900s, according to coffee lore, German coffee merchant Ludwig Roselius discovered decaf coffee by accident after a shipment of coffee beans was soaked in seawater during transit, naturally extracting some of the caffeine from the coffee beans.

A few years later, Roselius patented the first commercially successful means of decaffeinating coffee. But instead of just salt water, his method also used a more potent chemical solvent called benzene to finish the job.

We now know that when inhaled, even in small amounts, benzene can cause drowsiness, dizziness, and headaches, as well as eye, skin, and respiratory tract irritation. Over the long term and in high doses, benzene has been linked to cancer, blood disorders, and fetal development issues in pregnant women.

However, today, decaf coffee manufacturers have switched to safer decaffeination methods, though many still use potent chemicals to strip away caffeine. This is usually what you find in cheap decaf coffees.  Meanwhile, researchers have wondered whether any of coffee’s healthful compounds are lost along with the decaffeinated coffee process.

So is decaf coffee bad for you?  Is decaf coffee healthy?  What is the solution if you are sensitive to caffeine? We talked to experts including William D. Ristenpart, Ph.D., a professor of chemical engineering at the University of California, Davis, and director of the UC Davis Coffee Center, to understand the facts about how decaf coffee is made and its health benefits.

How is Decaf Coffee Made?

There are three key methods for removing caffeine from regular coffee beans: The most common uses a chemical solvent, another uses liquid carbon dioxide (CO2), and the last simply uses water.

They take green coffee beans, soak or steam them until the caffeine is dissolved or their pores are opened, and then extract the caffeine from the green coffee beans.

While the CO2 and water methods are considered chemical-free, the solvent method relies on synthetic chemicals such as ethyl acetate (naturally found in some fruits) and methylene chloride (commonly used in industrial applications such as in adhesives, paints, and pharmaceuticals).

Weaver's Coffee & Tea  roasts Mountain Water Process Decaf Coffees which is the most expensive decaf coffee. Mountain Water Process is an indirect decaffeination method using water and tends to produce the most flavorful coffee. The process begins with a chemical analysis to determine optimal conditions, and then the beans are steamed and prepared for extraction. The extraction process uses a water-based saturated solution that removes the caffeine while keeping the coffee's flavor compounds in place.

The Swiss Water Process is good at removing caffeine and without stripping other flavorful compounds from the green coffee beans. But it’s also more expensive to use the Swiss Water Process of to remove caffeine from coffee beans, and the process is difficult to produce at scale.

Coffee roasters will not hear a crack when roasting decaf because the crack represents moisture reaching a boiling point inside the bean and pushing through; with decaf, this isn't the case, because the cellular structure of the bean has been changed. This is an expensive way to remove caffeine from coffee beans 

How much caffeine in decaf coffee? None of these methods scrubs the bean of caffeine completely. While the Food and Drug Administration requires that at least 97 percent of caffeine be removed from coffee beans, some decaffeinated coffees can still contain between 3 and 12 mg of caffeine per cup of coffee.

Does Decaf Coffee have Risks?

While experts agree that the Swiss Water Process and liquid carbon dioxide don’t introduce any health risks, methylene chloride is controversial in some coffee circles.

When inhaled in small doses it can cause coughing, wheezing, and shortness of breath. At higher doses, it can cause headache, confusion, nausea, vomiting, dizziness, and fatigue, and has been found to cause liver and lung cancer in animals.

In 1999, however, the FDA concluded that the trace amounts you get in decaf coffee are too minuscule to affect your health. The agency strictly limits its presence to no more than 10 parts per million, or 0.001 percent, of the final product.

Coffee producers will sometimes say that beans decaffeinated with ethyl acetate are “naturally decaffeinated” because the compound is naturally found in some produce. But as with methylene chloride, the ethyl acetate is typically produced synthetically and carries some risks at high doses.

The bottom line, Ristenpart says, is that the solvents used in the decaffeination of coffee process today are much safer than they used to be, and they are generally found on coffee beans in only trace amounts.

How to Choose Decaf Coffee

Experts say you shouldn’t be concerned about the chemicals used in the decaffeination process. But if you are looking to minimize your exposure, you might want to know which decaffeination method was used on a particular bag of coffee beans.

This may be more challenging to find out than you think, Ristenpart says, because there are no specific labeling rules that require disclosing exactly how coffee was decaffeinated.

Is Decaf Coffee Healthy

Because decaffeination itself is generally considered safe, the bigger question is whether decaf coffee has the same health benefits as regular coffee.

This is a tough question to answer, says Angela M. Zivkovic, Ph.D., an assistant professor in the department of nutrition at the University of California, Davis, and we don’t yet have a firm answer.

A 2014 meta-analysis published in the journal Diabetes Care and led by researchers from Harvard found that those who drank six cups of coffee per day had a 33 percent lower risk of developing type 2 diabetes than those who drank no coffee. The reduced risk was seen for both decaf coffee and regular coffee.

Another study published in the Annals of Internal Medicine in 2008 found that coffee-drinking in general was not associated with a higher risk of dying from any cause, and even further, those who drank decaf coffee were slightly less likely than those who drank regular coffee to die from any cause.

Zivkovic says, however, that we should interpret such results with caution because “it is very possible and likely that people who choose decaf coffee are also making other ‘healthy’ lifestyle choices.”  

In short, though some studies suggest that decaf coffee is linked to health benefits, more research is needed.

Best Decaf Coffee

We still don’t know whether it’s the caffeine, or one of the thousands of other biologically active compounds and antioxidants (which decaf coffee seem to have, too, albeit at slightly lower levels), that may be responsible for coffee’s many health perks. What’s really clear, however, is that for people who experience insomnia, irritability, headaches, nausea, anxiety, jitters, and increased blood pressure after drinking too much caffeine, switching to decaf coffee may be a healthy option, says Edward Giovannucci, M.D., Ph.D., a researcher and professor of nutrition and epidemiology at Harvard T.H. Chan School of Public Health.