this article taken from:
www.a1b2c3.com/drugs/yer_02.htm

The xanthines draw a lot of attention, chief of which is caffeine. Others are theophylline and theobromine. All of the xanthines have a similar stereo-chemistry but each has its own unique set of properties.

For many years, and even now, in some sectors, yerbamate' was (is) thought to contain caffeine. It turns out that mateine is not identical to caffeine; it differs from caffeine in some rather dramatic ways.

Some members of the scientific community still resort to calling mateine a South American term for caffeine, or to maintaining, in perfect knowledge of the falseness of the assertion, that two substances so similar chemically must have the same properties.

Slowly, they are being forced to acknowledge the distinction between mateine and caffeine.

Modern studies seem to validate the difference between mate' and other xanthines-containing plants, such as guarana.

Stereo-chemical and clinical work on xanthines in the last couple of decades have shown that, though similar in structure, the members of this class have widely varying pharmacology.

In fact, there is only one effect that seems to be shared by all trimethyl xanthines: smooth muscle relaxation. It is this action that makes them with the exception of caffeine, whose smooth muscle relaxant effects are diminished by other side effects, good clinical dilators of the bronchi and hence useful in the treatment of asthma.

Over the past year, I have been giving the Yerba mate' tea to my patients who need to stop using caffeine-containing products for health reasons. I have had good feedback on the results. I like having a healthful substitute for coffee, tea and colas to offer them. K.L.P., M.D.

Chemical assays on mate' have traditionally looked for caffeine, and in such tests mateine, being a simple stereo-isomer of caffeine, would test positive. Until recently nobody has looked at the exact structure of the molecule--and, to my knowledge, nobody in the United States has ever made the attempt.

Researchers at the Free Hygienic Institute of Homburg, Germany, concluded that even if there were caffeine in mate', the amount would be so tiny that it would take 100 tea bags of mate' in a six ounce cup of water to equal the caffeine in a six ounce serving of regular coffee.

They make the rather astute observation that it is obvious that the active principle in yerbamate' is not caffeine! But then, we know for sure it is not caffeine, for caffeine is not present at all.

Mateine, then, has a unique pharmacology and it is unfair to compare it to caffeine (incidentally, guarana may not contain caffeine either, it may contain something that could be called guaraneine, however that substance looks like it is more deleterious than caffeine!).

Mateine appears to possess the best combination of xanthine properties possible.

For example, like other xanthines, it stimulates the central nervous system, but unlike most, it is not habituating or addicting. Likewise, unlike caffeine, it induces better, not worse, attributes of sleep.

It is a mild, not a strong, diuretic, as are many xanthines. It relaxes peripheral blood vessels, thereby reducing blood pressure, without the strong effect on the medulla and heart exhibited by some xanthines.

We also know that it improves psychomotor performance without the typical xanthine-induced depressant after effects.

Dr. Jose Martin, Director of the National Institute of Technology in Paraguay, writes, New research and better technology have shown that while mate'ine has a chemical constituency similar to caffeine, the molecular binding is different.

Mateine has none of the ill effects of caffeine. And Horacio Conesa, professor at the University of Buenos Aires Medical School, states, There is not a single medical contraindication for ingesting mate'.

Clinical studies show, in fact, that individuals with caffeine sensitivities can ingest mate' without adverse reactions.

The time has come, therefore, to discard the outmoded ideas that
(1) xanthines are all alike,
(2) that yerbamate' contains caffeine, and
(3) that mateine is identical with caffeine. It would be tragic indeed if nature created such a beneficial plant and then, through some bizarre quirk, contaminated it with caffeine.

It is more likely that mate' is, as some say, Natures most perfect beverage, or, as others maintain, the beverage of the Gods.

Summarizing the clinical studies of France, Germany, Argentina and other countries, it appears that we may be dealing here with the most powerful rejuvenator known to man. Unlike the guarana of the Tupi, the coca of the Incas, the coffee of India, or the tea of China, mate' rejuvenates not by the false hopes of caffeine, but simply through the wealth of its nutrients.

By Daniel Mowry, PhD


see these sites also:

www.noborders.net/mate/health.html

ma-tea.com/caffeine_substitute.htm

coffeetea.about.com/library/...yerba.htm