Consumers are increasingly trying to avoid caffeine due to unwanted health effects, including insomnia and irritability. The test could be another tool that eventually leads to a reduction in demand for products containing caffeine.

Chemists at Washington University School of Medicine in St. Louis are developing a quick, "dipstick" test that they say could represent the first home testing kit to detect the common stimulant.

 

Products do not always indicate whether they contain caffeine, and the caffeine content of similar food products can vary widely depending on the manufacturer.

 

Even drinks that are labeled "decaf" can contain detectable amounts of caffeine, experts say.

 

"We envisioned that a simple method to measure caffeine, even in hot beverages, such as coffee, would be of value to individuals and institutions wanting to verify the absence of caffeine," said study leader Jack Ladenson, a chemist at the university. "This will greatly assist individuals who wish to avoid caffeine."

 

Ladenson said he is developing test strips treated with a specific antibody that react by changing colour in the presence of caffeine.

 

The new test will be designed to be qualitative only, he said. It allows a person to quickly determine whether caffeine is present, but does not indicate the exact amount or concentration of caffeine.

 

In preliminary tests using coffee and cola, an experimental version of the caffeine test kit effectively distinguished caffeinated versions of these products from their decaf counterparts, Ladenson said.

 

Several studies have linked an increase in caffeine consumption with a higher risk of miscarriage among pregnant women. The US Food and Drug Administration has specifically advised pregnant women to avoid or limit their intake of caffeine.

 

Current tests to detect caffeine use sophisticated laboratory methods, including spectroscopy and chromatography. While caffeine-specific antibodies are commercially available, these antibodies are destroyed at high temperatures, like those of hot beverages, and consequently are not practical for use in home tests, the scientists say.

 

To develop the new immunoassay test, Ladenson and his associates obtained an antibody derived from the blood of llamas. The antibody is resistant to high temperatures due to its unusually stable structure.

 

They obtained the antibodies by repeatedly injecting the animals with caffeine to illicit an immune response to the drug. The researchers then cloned

 

the caffeine-specific antibody and combined it with other chemicals to facilitate caffeine detection.

 

In early laboratory studies, the antibody mixture was used to measure the presence of caffeine in both caffeinated and decaf versions of coffee and cola.

 

 

In general, the researchers found that caffeine test kit results were comparable to those of conventional chromatography tests and that the caffeine content of these beverages was accurately labeled.

 

The antibodies worked equally well in both hot and cold beverages and did not appear to show any false readings caused by structures that are similar to caffeine, Ladenson says. He has filed patents related to the research.

 

The study will appear in the 1 June edition of the American Chemical Societies Analytical Chemistry.

 

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Caffeine... Is It Really All That Bad?

 

Caffeine (kaf-en') - an alkaloid drug, obtained from coffee and tea, that has a stimulant action, particularly on the central nervous system. It is used to promote wakefulness and increase mental activity.

 

Sources and Related Compounds

 

Caffeine is one in a group of compounds known as methylxanthines. The other two compounds are theobromine and theophylline and are found in cocoa and tea, respectively. Caffeine is found in coffee, tea, cocoa beans, and kola nuts. The following table lists average amounts of caffeine in the most common sources: \

 

 

The Physiology of Caffeine

 

Caffeine is absorbed rapidly and is distributed throughout the body water within about an hour. It has a metabolic half life of about three hours and is excreted as a methylxanthine derivitive (in both urine and to a lesser extent, feces). Caffeine is a cardiac muscle stimulant, smooth muscle relaxant, and a central nervous system (CNS) stimulant. One mechanism behind the latter is an increase in the excitiability of neurons in the CNS. Caffeine also acts as a diuretic, stimulates gastric acid secretions, and increases plasma glucose and free fatty acid concentrations. These physiological effects of caffeine are related to both the drawbacks and benefits of this drug.

 

The Drawbacks of Caffeine

• Dehydration is a major drawback of caffeine consumption, and results from the drugs ability to increase urine production. If you are not careful about replacing fluids with your morning cup of joe, you could end up dehydrated pretty quickly - especially in our already-dry environment. Now would be a good time to reread the Nutrition Paige regarding hydration!

• In addition to dehydration, caffeine causes some people to get jittery stomachs or "coffee stomach" - which can be quite uncomfortable and mask any potential benefits.

Some of the biggest drawbacks of caffeine have nothing to do with caffeine itself. For example, some people don't like black coffee and end up putting cream, sugar, flavoring, etc. into their coffee. A cup of black coffee every day only adds about 10 calories but a cup of joe with all the bells and whistles or a specialty drink like a mochas or lattes can run in the hundreds of calories - not to mention add extra sugar and saturated fat to the diet.

 

For those watching their weight, these coffee habits can be detrimental. Remember, the powdered non dairy creamers have coconut oils, which also have saturated fat. Skim milk and an occasional Equal in place of sugar is a good compromise if plain black coffee doesn't float your boat.

 

For some, a cup of coffee in the morning replaces a healthy breakfast as it tends to curb the appetite. If this is the case for you, you may want to put off the caffeine for later and see how much energy a good breakfast gives you!

 

An obvious drawback to any drug is the withdrawal symptoms that accompany its abuse. For caffeine, this includes primarily headache, and nausea and vomiting are more severe side effects of withdrawal.

 

 

The Benefits of Caffeine

• An increased alertness and wakefulness is probably the primary reason people consume caffeine of any form. BUT...did you know that caffeine's perk-me-up quality is only effective when you are truly fatigued? In other words, if you get plenty of sleep, coffee is probably not doing a whole lot of good - and the perceived alertness is just that... perceived! (but, there is certainly nothing wrong with the placebo effect - as long as you can minimize the drawbacks above).

• Athletes commonly consume caffeine for its proven performance enhancing effect. At first it was thought that because caffeine stimulates the release of fats into the blood, the working muscles would burn more of these fats, essentially sparing limited muscle glycogen. This has never been proven, however. While caffeine does release fats into the blood, this is probably not significant for competitive athletes who are already "wired" on adrenaline. A more likely explanation is the ability of caffeine to make exercise seem easier due to its stimulant effect on the brain, which may reduce the fatigue associated with long bouts of exercise.

Who Should Avoid Caffeine?

Caffeine should be avoided by those with any of the following clinical conditions:

• irritable bowel syndrome

• iron deficiency

• chronic fatigue

• cardiac arrhythmia

• kidney stones

• osteoporosis

• ulcers

• PMS

This is not meant to be a comprehensive list by any means, but these are some of the major conditions where caffeine should be avoided. Also, patients should be made aware of any caffeine found in medications in case they are sensitive to certain levels of caffeine.

 

The Caffeine Bottom Line

 

Most of the studies linking caffeine (coffee consumption) with health problems are inconsistent. Increased caffeine consumption has been associated with elevated cholesterol, fibrocystic breast disease, rapid heart beat, and some cancers. Studies showing either a relationship or no relationship seems to be about equal in number.

 

In 1986 the American Journal of Epidemiology reported a 25 year follow up study on 3000 people which showed that men who drank more than 5 cups of coffee a day had an increased mortality - but this was not the case for women.

 

The jury is obviously still out on the hazards of caffeine, but most of the studies showing some link between caffeine and a health risk report levels of more that 4 cups of coffee a day. In my opinion, caffeine is like anything else - used in moderation (200 mg a day or so) it is probably harmless.  For those of us who choose to consume that tasty beverage called joe, it's important to recognize some of the drawbacks and make sure we minimize them.

 

If you can't function on less than 4 cups a day - I would definitely consider cutting back slowly down to a more moderate level.

 

If you really enjoy your one cup a day - relax and enjoy!