Article: Interview with Dr Vincent Lebot, a leading expert on kava

Jun 26, 2020cultivars

Interview with Dr Vincent Lebot, a leading expert on kava

Dr Vincent Lebot photographed in June 2020, the world's leading kava scientist and co-author of Kava: The Pacific Elixir

Dr Vincent Lebot, June 2020.

Anyone who has ever studied kava or tried to find scholarly material on it has inevitably encountered the name of Dr Vincent Lebot. Dr Lebot has authored or co-authored a great number of publications on the kava plant, including the landmark Kava: The Pacific Elixir (co-authored with Lamont Lindstrom and Mark Merlin, 1997) and Buveurs de Kava (co-authored with Patricia Siméoni, 2019). Between them, the two most comprehensive works on kava ever written.

Dr Lebot is often regarded as the father of modern kava science. It would be hard to find anyone who has done more to broaden Western understanding of both the plant and the beverage. His work on kava's history, biology, chemistry, and pharmacology has inspired multiple other researchers and informed government officials, journalists, and countless kava drinkers, growers, and entrepreneurs.

One of our founding members had the pleasure of sharing some fresh, green kava with Dr Lebot in Port Vila a while back. We have stayed in touch since, occasionally discussing aspects of kava science and the industry. After one recent exchange, the idea for this interview was born. We hope you enjoy it.

How Dr Lebot discovered kava

Many of our readers first encountered kava through your co-authored book, Kava: The Pacific Elixir, or one of the numerous articles you have written about kava over the last three decades. You are widely known as one of the world's leading kava experts. Less well known is how you discovered kava and what made you so interested in studying it. Could you tell us how that began?

When I arrived in Vanuatu as a volunteer to teach agriculture at Tagabé, near Port Vila, in November 1980, there were no kava bars in town and kava was not drunk on Efaté (the island Port Vila sits on). A few weeks later I visited several outer islands and drank my first kava on Malekula. It was freshly harvested kava, so it was pleasant to drink. The beverage had a liquorice-like taste and the effect was surprising but enjoyable. As soon as I came back to Vila, I visited the few libraries around and read everything that existed on this fascinating plant. It became clear very quickly that such an amazing plant was poorly documented scientifically, and I decided to work on it.

My first project, with the help of my students at the agriculture school, was to visit all 82 islands of Vanuatu and collect all the different kava varieties, establish a germplasm collection at Tagabé, and characterise the accessions morphologically after recording the ethnobotanical knowledge associated with each variety. It took years to collect them all and describe them. I also set up agronomical trials to understand the growth of the plant. I wrote a few project proposals and managed (thanks to French Aid) to equip a laboratory to analyse all the accessions. At that time I was doing only the extracts at Tagabé and then hand-carrying them with me to France for HPLC work.

Meanwhile, kava was becoming an important cash crop in Vanuatu. Kava bars were opening in Vila, Santo, and Nouméa, encouraged by churches, women's groups, and political leaders to strengthen national identity just after Vanuatu's independence on 30 July 1980. The Secretariat of the Pacific Community got interested in the work and funded a regional survey of kava genetic resources. Thanks to SPC, I was able to visit all the Pacific islands where kava was cultivated in the early 1980s, collect all existing varieties, and analyse them. I consolidated all that research into a PhD thesis I defended in Montpellier in November 1989. So part of my research was sheer personal scientific interest in this underutilised plant, and part of it was to support the development of the cash crop in the region.

Cultivar selection and the role of kavain

In your work, you have often highlighted the great diversity of kava cultivars across Oceania and the significant differences between them. You have argued that since kava became domesticated a few thousand years ago, kava growers and drinkers have been purposefully selecting and propagating cultivars on the basis of their characteristics, and in particular preferring kava with higher kavain and lower DHM. Does this seem to be the main criterion or have other factors also played a role in driving the propagation of new cultivars? Has this tendency been observed in Vanuatu only, or was the same true in other kava-growing regions?

Before first contact with Europeans, kava was drunk fresh around the Pacific. When the Europeans started to prohibit kava, then a few communities started to dry it so they could prepare it at home any time the missionaries or the colonial power were not controlling their traditional way of life. Westerners always disliked kava: they did not like its appearance, its taste, or its effect (read Captain Cook's logbook), so very soon they wanted to eliminate it. I think the consumption of dry kava is a modern phenomenon. Pacific Islanders were uprooting kava whenever they wanted to drink it (once kava is in the ground there is no rush to harvest it). When growers drink fresh kava they appreciate the taste, but no one drinks kava for its taste, even when it is fresh.

Kava is always drunk for the relaxing character it produces, and this has to be fast (a few minutes after absorption) and pleasant. To this day I still believe that kavain is the most interesting kavalactone, the one drinkers are looking for, because it produces a fast, pleasant, not long-lasting effect that disappears quickly. When I analyse kava varieties, I can see that the good ones are rich in kavain, and the bad ones are poor in kavain.

Over the years the situation has appeared a bit more complex than I thought, because in the 1980s and 1990s I was using an HPLC protocol and scanning the six major kavalactones at 240 nm. In doing so, I was underestimating yangonin and demethoxyyangonin in the chemotypes. So when I now look again at those chemotypes, it is still true that the best chemotypes are rich in kavain (much higher than in the poor ones), but some bad varieties are also rich in kavain and other major KLs. What seems to characterise a bad variety now is that it is also rich in flavokavins, while the good varieties are poor in flavokavins. Yangonin and demethoxyyangonin are not very bioactive kavalactones (as far as we know), so it is doubtful that they played a role during the selection or domestication process. On the other hand, what we observe is that in countries where kava has now been consumed in dry form for decades, if not centuries, the chemotypes are quite different. Frankly, we need more research on that.

The migration of cultivars across the Pacific

Is there any genetic evidence suggesting that there are kava cultivars in Vanuatu descended from cultivars developed on other Pacific Islands? Kava was a "canoe plant" taken east across the Pacific. Could any cultivars descended from those pioneer specimens have later returned home to Vanuatu from the west, perhaps through inter-island trade?

As far as I know, all kava cultivars found around the Pacific Islands are decaploids (ten sets of chromosomes) and are sexually sterile: they do not produce seeds and are always propagated vegetatively. When we did an isozyme survey in the early 1990s (isozymes are water-soluble proteins used to detect genetic distances), we found there were basically three groups of kava cultivars: the so-called nobles (many different varieties or morphotypes within this group); and the so-called two-days, with a major group in Vanuatu and another closely related one in PNG. Within each group there were many somatic mutants: plants mutating through vegetative propagation and exhibiting different morphological traits such as a purple stem, a striped stem, and so on.

Much later we did another survey using DNA markers (SSR and DArT) and found the same picture: we have two-day varieties, with a few from PNG (Isa, Iwi, et al.), and we have the nobles found around the Pacific (except in PNG, although I found one on the small island of Baluan offshore Manus). DNA markers confirmed the isozymes, but our sample was too small and we need to do more studies on the wild ancestor (Piper wichmannii) and on varieties from Eastern Polynesia (Tahiti, Marquesas, and Hawaii) which are morphologically different from others, although noble from a chemical point of view.

The ancestors of the Polynesians probably collected good varieties in Vanuatu before distributing cuttings to all the islands they visited, and they might have reintroduced them in the south of Vanuatu, but this is speculation and nobody will go back to double-check. Unfortunately, since they are all nobles, they all have the same fingerprint, so it is difficult to trace them. When we generated dendrograms to compare the SSR and DArT pictures, they were slightly different (VandenBroucke, H., Mournet, P., Malapa, R., Glaszmann, J.C., Chair, H., Lebot, V. 2015. Comparative analysis of genetic variation in kava (Piper methysticum) assessed by SSR and DaRT reveals zygotic foundation and clonal diversification. Genome 58(1):1-11). So, here again, more research is needed to clarify the overall picture of this plant's domestication.

Noble vs non-noble kava

In your research, you have identified two broad groups of kava cultivars: the noble cultivars and the non-noble cultivars (which include "two-day" kava, medicinal kava, and wild kava). Could you briefly characterise the difference between these groups? Is the development of noble kava a direct result of cultivar selection? If so, why have so many two-day cultivars remained in existence in Vanuatu?

A copy of Buveurs de Kava, the 2019 French-language kava reference co-authored by Dr Vincent Lebot and Patricia Simeoni

A book co-authored by Dr Lebot.

In the early 1980s, two-day cultivars were very rare in Vanuatu gardens. You can check the statistics published in Lebot, V. and P. Cabalion. 1988. The Kavas of Vanuatu. South Pacific Commission Technical Paper no. 195, 191 pages, Nouméa, Nouvelle Calédonie. We did a survey under the auspices of the FAO and counted all the plants in the ground at the time. Two-days were unusual. Some farmers were keeping a few plants but were not drinking them, they were using them occasionally as a medicinal plant.

During the so-called kava boom of the late 1990s, German companies did agronomical trials and discovered that two-days out-yielded the nobles on dry matter, and since nobles and two-days had similar total kavalactone content, they decided to buy two-days despite my efforts to discourage them. They were very arrogant, and when you come from Germany and visit Vanuatu, you think Science is on your side and that the locals do not know. Their position was that when they did an acetonic extract, it was not important (at the time) what the chemotype was; they just needed an acetonic extract as rich as possible to maximise their profit. A few years later they came back to my office like children having done something wrong and were asking me if I had heard anything about "hepatotoxicity".

Years after that, young farmers who lost traditional knowledge started cultivating kava as a cash crop. We also had traders who advocated that two-day kava was good, and even bureaucrats who were convinced that two-day varieties were good. Fortunately, the Kava Act was passed in Parliament in December 2002 with a complete list in the appendix of the legal varieties (the nobles) and the illegal varieties (two-days and wichmannii). The Act explains clearly that if a company wants to purchase two-day kava for particular purposes, they can, provided they supply an official letter explaining why. As far as I know, Vanuatu has never received such a letter.

Safety concerns around non-noble varieties

Is the difference between noble and non-noble kava mainly a matter of quality and type of experience, or are there documented safety concerns about non-noble cultivars?

Until a few years ago it was just a matter of quality, because we knew that some kavalactones produced more pleasant physiological effects than others. Following the German and European position and the numerous scientific investigations that they triggered, many studies have shown that kavalactones are harmless, but there is a group of molecules which is still controversial (although they are not water-soluble): the flavokavins. The two-day varieties (as well as wild kava) are much richer in flavokavins than the nobles, and we do not yet know whether this is why they produce the terrible hangover that drinkers report. More research is needed. There are now safety concerns because some studies have documented potential risk with flavokavins, but at a level much higher than those found in the plant.

Kava beverage vs solvent extracts

Around the world, kava is available in two forms: as a fresh or dried root that is made into a beverage via cold-water extraction; and as kavalactone extracts made using various organic solvents or, more recently, supercritical CO2. What is the main difference between such products? What are the safety concerns regarding extracts made using chemical solvents, and do they apply to all kinds of chemical solvents?

The definition of the word "kava" is the cold-water extraction of the peeled underground organs of noble varieties of Piper methysticum. Kava is a beverage (like tea or coffee), and an extract is not kava (like caffeine is not coffee). Kava per se is not dangerous; we know that because it has been drunk for centuries. It is not a drug, because it is not addictive and does not produce side effects when drunk in moderation. Extracts made from dried or fresh kava roots can produce very different products from a cold-water extraction.

The Germans officially recognised and announced to the world that the acetonic extracts they were producing in Germany with uncontrolled imported raw material at that time were potentially dangerous. This is what they claimed. Unfortunately, they called their products "kava" while it was something completely different, and they destroyed the reputation of kava while nobody was drinking kava in Europe. Solvent extraction can extract everything (including mycotoxins or other toxins present), and the chemical composition of the extract will be very different from the suspension we drink, because kavalactones are lipid-like compounds that are not water-soluble. We have centuries of safe use of kava in the Pacific (half of the population drinks, the males, and half do not, the females, so any potentially toxic effect would be very easy to detect statistically, and none is observed). Extracts do not have this history of safe use, so we do not know. We need more data.

(Our take on this aligns with Dr Lebot's. We have written more about it in Kavalactone Extracts vs Traditional Kava: What You Need to Know.)

Why Fijian, Tongan, and Samoan drinkers focus less on cultivars

Some people argue that the way kava is currently drunk in Tonga, Samoa, and Fiji (relatively heavily diluted, made from dried roots) makes the appreciation of unique cultivar characteristics much more difficult, and perhaps explains why locally there is much less emphasis on cultivars, as opposed to parts of the plant (e.g. waka or lewena). Is this accurate?

I would tend to agree. This is why kava (yaqona in Fiji) is classified into waka (roots), lewena (stumps), and kasa (peeled basal stems): these correspond to three different products with decreasing kavalactone content (and therefore decreasing prices). Consumers know they will prepare different brews from these three products, and the variety of kava is not that important, especially as there are no two-days in Fiji, Tonga, or Samoa. If I recall properly, I found only one called "Honolulu" in Viti Levu, and it was probably a recent introduction (with no Fijian vernacular name).

What makes good kava

What, in your view, makes good kava? Do you have a favourite cultivar? Beyond cultivar, what other factors determine the quality of the plant material? What is the best method of processing kava roots, preparing the beverage, and drinking kava?

Of course, I can drink only nobles, but among the nobles some varieties (like Borogu here in Vanuatu) make me dream too much at night. I do not like that. A good kava is one which gives you a fast, sudden, relaxing effect that has already disappeared by the time you have your dinner. Kava is a starchy solution and is heavy on the stomach, so I do not want to drink too many cups to reach that relaxing effect; it has to be concentrated enough.

Some cultivars like Kelai, Visul, Melomelo, Palarasul, and Ni Kawa Pia are all good varieties if prepared correctly. Here in Vila we drink fresh kava, so it is very important that it is well cleaned and properly peeled to remove bitterness. Unfortunately, we grow very little on Efaté, so kava is imported from the outer islands and the quality is sometimes disappointing. Nothing can beat freshly harvested kava consumed a few hours after harvesting (oxidation is the problem). Nowadays hygiene is also a serious factor that attracts attention.

The future of kava outside the Pacific

Kava is becoming increasingly popular outside the South Pacific. In particular, in the United States we have seen a growing number of kava bars. What do you think about kava's chances of becoming accepted as a mainstream food product worldwide? What are the major challenges and risks?

It is going to be very difficult, because the Germans and the Europeans have damaged the reputation of kava for the very long term. Same in Australia, where official authorities recognise that locally produced alcohol kills thousands every year but are restricting the importation of kava for personal use to only four kilograms (and launching a "consultation" to see if this is acceptable). In the meantime, the Pacific Island countries are importing without restriction thousands of litres of alcohol produced in Australia. This is not fair trade.

The Europeans will not lift their ban any time soon, because there is no market for kava in Europe. The situation in the US is very fragile, and official authorities (bureaucrats around the world prefer to follow their colleagues' position rather than learn about the product. Part of this attitude is laziness, part is arrogance because of their position). Westerners are very much hostile. If Pacific Islanders expect that the markets will open, they are wrong.

At the moment they do not have a good product. A dried kava root is not a product. They need to move to the next step: process kava and add value to it and produce attractive products. Already bottled, with an attractive colour, smell, and aroma, or attractive powders, easy to prepare (some instant kava made in Vanuatu is already very good and can reach new markets). The major risk is hygiene (more than flavokavins, I think), and as kava is first of all a food, it is very important that it is organically grown (no pesticide residues) and not polluted by contaminants of all sorts (bacteria, etc.).

Kava farming outside the Pacific

The growing demand for kava might make it tempting for farmers in other tropical parts of the world to consider growing kava. According to some reports, some farmers in Southeast Asia and Central America have already started growing kava. Do you think this represents a threat to kava growers in the South Pacific?

Of course, it is not possible legally to patent kava, just like you cannot patent a potato. You could patent a recently created kava variety, but there are none; all are old. The Kiwis and Aussies are planting Cabernet Sauvignon and Pinot Noir and not paying fees to the French. The only way to protect Pacific Island kava is through an Appellation of Origin system (like French wines, Scottish whiskies, Indian teas, Korean ginseng, and so on).

The Pacific Islands have to produce their own quality products and convince the rest of the world that they are good. They should not expect others to tell them what to do; they have to develop good local products for themselves first, and then make sure they can reach new markets. It is possible that other large tropical countries will start to cultivate kava, and it will be impossible to stop them. The Pacific Island countries should not waste their time. They should do their homework and move forward rapidly.

About Dr Lebot

Vincent Lebot is a root and tuber crops breeder working for CIRAD (www.cirad.fr). He obtained his PhD in 1989 in Montpellier, France, and has been working on root and tuber crops for the last 40 years. His studies focus on the chemical composition of the underground organs and their relation with quality. He was the scientific coordinator of SPYN (the South Pacific Yam Network), TANSAO (the Taro Network for South East Asia and Oceania), and INEA (International Network for Edible Aroids). He is presently focusing on sweet potato breeding for biofortification and resistance to abiotic stresses. His list of publications can be found at publications.cirad.fr/auteur.php?mat=1389.