Decaf is not caffeine-free

[David Baxter]

Decaf is not caffeine-free
Monday, 16-Oct-2006

Coffee addicts who switch to decaf for health reasons may not be as free from caffeine's clutches as they think. A new study by University of Florida researchers documents that almost all decaffeinated coffee contains some measure of caffeine.

Caffeine is the most widely consumed drug in the world. And because coffee is a major source in the supply line, people advised to avoid caffeine because of certain medical conditions like hypertension should be aware that even decaffeinated brew can come with a kick, UF researchers report in this month's Journal of Analytical Toxicology.

"If someone drinks five to 10 cups of decaffeinated coffee, the dose of caffeine could easily reach the level present in a cup or two of caffeinated coffee," said co-author Bruce Goldberger, Ph.D., a professor and director of UF's William R. Maples Center for Forensic Medicine. "This could be a concern for people who are advised to cut their caffeine intake, such as those with kidney disease or anxiety disorders."

Despite caffeine's widespread use, most medical texts have no guidelines for intake, Goldberger said, but even low doses might adversely affect some people. So UF researchers set out to conduct a two-phase study designed to gauge just how much caffeine is likely to turn up in decaffeinated coffees.

First they purchased 10 16-ounce decaffeinated drip-brewed coffee beverages from nine national chains or local coffee houses and tested them for caffeine content. Caffeine was isolated from the coffee samples and measured by gas chromatography. Every serving but one - instant decaffeinated Folgers Coffee Crystals - contained caffeine, ranging from 8.6 milligrams to 13.9 milligrams.

In comparison, an 8-ounce cup of drip-brewed coffee typically contains 85 milligrams of caffeine.

In the study's second phase, scientists analyzed 12 samples of Starbucks decaffeinated espresso and brewed decaffeinated coffee taken from a single store. The espresso drinks contained 3 milligrams to 15.8 milligrams of caffeine per shot, while the brewed coffees had caffeine concentrations ranging from 12 milligrams to 13.4 milligrams per 16-ounce serving.

Even though the amount of caffeine in these coffees is considered low, some people could conceivably develop a physical dependence on the beverages, said co-author Mark S. Gold, M.D., a distinguished professor of psychiatry, neuroscience and community health and family medicine at UF's College of Medicine.

"One has to wonder if decaf coffee has enough, just enough, caffeine to stimulate its own taking," Gold said. "Certainly, large cups and frequent cups of decaf would be expected to promote dependence and should be contraindicated in those whose doctors suggested caffeine-free diets."

And even moderate caffeine levels can increase agitation, anxiety, heart rate and blood pressure in some susceptible individuals, Goldberger said.

"Carefully controlled studies show that caffeine doses as low as about 10 milligrams can produce reliable subjective and behavioral effects in sensitive individuals," said Roland Griffiths, Ph.D., a professor of behavioral biology and neuroscience at the Johns Hopkins School of Medicine. "More than 30 percent can discriminate the subjective effects of 18 milligrams or less. The present study shows that many decaffeinated coffee drinks deliver caffeine at doses above these levels.

"The important point is that decaffeinated is not the same as caffeine-free," Griffiths added. "People who are trying to eliminate caffeine from their diet should be aware that popular espresso drinks such as lattes (which contain two shots of espresso) can deliver as much caffeine as a can of Coca-Cola - about 31 milligrams."

McCusker RR, Fuehrlein B, Goldberger BA, Gold MS, Cone EJ. TECHNICAL NOTE: Caffeine Content of Decaffeinated Coffee. J Anal Toxicol. 2006 Oct; 30(8):611-613 [Abstract]

[Halo]

Thanks for article David but now I have a question about caffinated beverages. Does anyone know the "average" recommended daily cups of caffinated beverages one is to consume in a day. I think that I am probably severely over the limit per day as I am a caffeineaholic (if there is a such thing) and would like to know what I should be intaking.

Thanks

[David Baxter]

I honestly don't know. I was surprised at not only how much caffeine there is in decaf but the range of caffeine levels from one brand to the next. I also know that some people are a lot more sensitive to caffeine than others, and personally I found that my sensitivity increased as I got older.

[Halo]

I remember a while back watching I think it was a Dateline Investigation Special where they had people go to different coffee shops and request decaf coffee and they tested them and I remember being surprised at how many of them were not actually decaf at all. I just goes to show that you don't always know what you are getting when you buy/order decaf.

[Halo]

I actually found this information and I thought that I would post it for others in case they are interested as well:

Most experts agree that moderation and common sense are the keys for consuming caffeine-containing foods and beverages. Moderate caffeine consumption is considered to be about 300 mg. which is equal to 3 cups of coffee, but this depends on the individual and can vary from one to several beverages. Consumers with certain health problems may wish to consult with their physician or health care provider about caffeine consumption.

"Moderate tea or coffee drinkers probably need have no concern for their health relative to their caffeine consumption provided other lifestyle habits (diet, alcohol consumption) are moderate, as well."

The American Medical Association

[ThatLady]

Some people are more susceptible to the effects of caffeine than others. If you're a highly anxious person, chances are that weaning yourself off caffeine may help quite a lot. For those who aren't sensitive, I'd say no more than three cups of coffee a day. You also have to remember that there's caffeine in many soft drinks. It's always good to read lables.

[foghlaim]

For those who aren't sensitive, I'd say no more than three cups of coffee a day.

hmm.... i seem to remember being told to stop drinking cofee... a long long time ago..(by a psych) and then being told (by some one else) because it's really only the thing i drink.. not to cut it out just cut it down.. I managed to cut it from 10\15 a day to approx 10 depending on the day and what i was doing. these days i drink somewhere between 8 and 12.
Just thinking... not one person said anything while i was in hospital about my coffee consumption.. maybe because it was the only drink i was drinking??? anyway for cofeeholics like me... three cups a day would be torture.. i mean three!!! i usually have two when i get up and that's before the day really starts. I like me coffee.

[sister-ray]

thanks for the article, I had heard this ages ago, I dont drink coffee anymore, its makes me jittery, I do drink a fair amount of tea, but couldnt live without that it would be torture At night I have Barleycup, from the health shop. My GP told me too much caffeine can interact with some drugs too, some migraine tablets Ive had have caffeine in them, yet caffeine can cause headaches dont understand that one.

[momof5]

Neat article David, we were just discussing this on Sunday. I was surprised to hear of this since I thought that the regulations on advertising being true are so strict. To advertise that something is caffene free and find it isn't must be upsetting to some.

For me I cut down on it only cause I had to with my heart. I still drink a good bit of it, about 3 cups a day. And I would say that it is half and half as it is Maxwell house lite, but now I wonder how lite it really is?

[ThatLady]

I think they get around the advertising by labeling ingredients. You're expected to read them all ... even those that are a foot long and can't be pronounced by anyone but Klingons!