AS pressure mounts on European and other countries to lift the ban placed on kava imports, the experts and producers of kava around the Pacific are joining forces to publicise the benefits of this age-old root plant to offset any negativity.
Holding the helm of this counter-publicity drive in Fiji are the University of South Pacific Professor of Organic Chemistry Subramaniam Sotheeswaran and Kadavu chief Ratu Josateki Nawalowalo.
"In a recent study in collaboration with the organic chemists at the USP, the Saitama Cancer Centre Research Institute in Japan, has shown that kava may have promising anti cancer activity paralleling the anti-cancer activity of green tea,'' Prof Sotheeswaran told the Sunday Times.
"This may even account for the lower incidence of cancer amongst the kava drinkers in the South Pacific,'' he said.
"Kava is a time-tested traditional drink and a proven herbal remedy with interesting and useful pharmacological activities. If it is used in moderation and not abused, it will benefit the user.''
Prof Sotheeswaran, who has carried out many researches on kava, said its benefits should be advertised and the product promoted as an anti-anxiety and anti-stress herbal medication from the South Pacific.
He was also one of the speakers at a seminar on "Scientific Aspects of Kava" held at the USP last Wednesday.
The growing kava export market was hit hard in year 2001 as a result of a ban on its imports based on the claims that it could be dangerous for liver.
Kava export to Europe, United States of America and other countries stopped since 2002.
In a meeting of kava stakeholders in Brussels last August, it was argued that there was no conclusive evidence on the claims that kava capsules may have caused liver toxicity in European consumers. Some experts also met in Berlin and London early this year and have made representations to the Health Authorities in Europe to lift the kava export ban to Europe.
Another meeting of kava experts is planned for this November in Suva to look at new kava science, the efficacy and safety of kava and the quality control of its exports in case the ban is lifted in the near future. Kava, endemic to the South Pacific, is the popular name for the plant called piper methysticum.
Fiji as well as Pacific Islanders have been making the brew from the root and the stem of the plant, which they mix with water, for centuries.
It is used as both a ceremonial drink and a recreational beverage, mainly drunk by men in the evenings after work.
"It was interesting to note that kava belongs to the plan genus Piper of the family Piperaceae and is a close cousin of the plants from which the spice pepper and betel leaves are obtained,'' Prof Sotheeswaran said.
Over the years kava products became a popular complementary health care product to the synthetic chemicals called benzodiazepines in the treatment of anxiety, insomnia, depression and also stress in some European countries.
Its popularity is said to have peaked in the late 1990s as a non-addictive medication that was less toxic and had fewer side effects than the benzodiazepines.
According to Prof Sotheeswaran, about 17-25 per cent of the population in USA experience anxiety syndromes and kava contributed a great deal, as a popular herbal medicine, to alleviate that.
He said tablets called nexus, which contained kavalactones, became very popular in the USA as an antidepressant medicine and as a complementary medicine to prozac.
"Kava products sold in Europe and the USA are made from organic solvent extracts obtained from kava.
The observed pharmacological effects of kava drinking such as sedative activity and soporific (sleep-inducing) activity are due to the kavalactones in the kava products. The kavalactones also have a central nervous system relaxing activity. Kava drinkers in the South Pacific including Fiji experience this effect too.
"As we all know in the South Pacific, kava is drunk as a water extract obtained mainly from the roots,'' Prof Sotheeswaran said.
"The roots contain, apart from the pharmacologically active kavalactones, carbohydrates, which produces glucose during digestion.
Professor Sotheeswaran explained that the glucose produced was used by the body cells as energy for biochemical cell functions.
He said carbohydrates were not present in most of the kava products sold as kava pills in Europe and the USA adding that it was claimed that the water extracts contain a small protein molecule called glutathione, which may detoxify any ill effects of excess kavalactones in the liver.
This was not so with kava pills.
"Kava pills do not contain this detoxifying chemical and this may explain the liver toxicity cases reported in Europe.
"Some pigments present in the water extracts of kava called flavokavins may be responsible for the dry skin condition experienced by some heavy kava drinkers." Professor Sotheeswaran also said pills were made from the cheaper kava peelings, which was a waste product in the South Pacific.
He said it had now been shown that an organic compound called pipermethystine was present in some of the kava raw material used for making kava pills and may also be responsible for the liver problems reported in Europe.
"In human trial experiments, it has been shown that a 200 mg dose of kavalactones caused sedation in 29 patients with anxiety syndromes not caused by mental disorders.
"After a week of taking the German kava pills, with the brand name Laitan, the patients showed a reduction in overall scores of anxiety symptoms.
"It has been now established that the kava dosage for antianxiety effects should not generally exceed 300 mg of kavalactones per day, a dose that is derived from roughly 3g of dried kava root powder. When used in normal therapeutic doses, kava appears to be a safe and an effective antianxiety drug and a good muscle relaxant.''
According to Professor Sotheeswaran, some heavy kava drinkers were underweight and of poor health because of the anaesthetic activity of the drink.
He said some kavalactones have anaesthetic activity and the lining of the mouth became anaesthetised, thus depriving the drinker of the sensation of taste.
"This and the fact that the kava drinker is sedated is responsible for the heavy drinker not consuming sufficient food and for poor heath.
"It should be mentioned that kava consumption might adversely affect the ability to drive a vehicle.''
Research has also shown that some kavalactones can function as cardiovascular protectors by reducing platelet aggregation via the inhibition of an enzyme and inhibition of thromboxin production. Thromboxin is a blood-clotting enzyme.
The ban on kava products was prompted by 76 case reports, mainly in Europe, that the use of kava containing medications caused liver damage such as abnormal liver function (increased liver enzymes), jaundice, hepatitis, liver failure and death in a few isolated cases.
However, Prof Sotheeswaran said an in-depth investigation carried out in Germany by the Phytopharm Consulting Group headed by Dr Joerg Gruenwald showed that the claims of severe hepatotoxic effects of kava pill could not be proven. He said the action to ban kava products was taken on the basis of insufficient data provided by the 76 case reports.
"Out of the 76 cases, only 4 liver toxicity cases can be linked to kava pills. But, even these 4 people have been taking other medications in addition to taking kava pills. "Hence we could say that the medical reports are nowhere near a conclusive body of evidence that kava capsules might have caused acute or sub-acute liver toxicity in European kava pill consumers.''
Prof Sotheeswaran said the water extract of kava has been drunk for centuries in the South Pacific with no recognition of definite liver problems associated with normal kava intake. He said one reason for 76 cases of suspected liver toxicity in Europe could be because the extracts of kava used in the South Pacific and in Europe and USA were different. "While, in the South Pacific, we consume only the water extract from roots, in Europe and the USA, organic solvent extracts from kava peelings are used to make pills.
"At the USP, we have shown that these products are not identical.''
He suggested using water extracts from roots in making the kava pills adding that this could be done by freeze drying the water extracts of kava roots and making the pills from the resulting powder. He said it would be better to avoid kava peelings to make pills as was done prior to the ban by the German Pharmaceutical Industries.
"The quality of kava roots exported should be controlled. The current quality control methods in place only look at the percentage of kavalactones in the export materials. This is not sufficient.
The quality control analysis should also indicate whether or not any undesirable organic compounds are present in the export materials.''
He said the safety of any medical preparation depends on the amounts as well as the types of organic compounds present in the raw materials.
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