Pueraria mirifica
Pueraria mirifica, also known as กวาวเครือ kwao krua, is a plant found in northern and northeastern Thailand and Myanmar.
In Thailand, the plant is known as "kwao krua kao", the 'kao' meaning white which distinguishes Pueraria mirifica from other plants with tuberous roots also sharing the 'kwao krua' designation, such as Butea superba, commonly called kwao krua deng and the 'black' and 'dull grey' kwao krua plants. The species was definitively identified as Pueraria mirifica in 1952.
Dried and powdered, the tuberous root of Pueraria mirifica has a history of domestic consumption in Thailand in traditional medicine.
History
Evidence of the use of Pueraria mirifica can be identified as early as the 13th century written on palm leaves, and translated into English and published in 1931, with the instructions:
To take the tuberous root of Pueraria with big leaves, pound and blend with cow's milk. The benefits of this medicine is to support memory, talk big, and be able to remember three books of the astrology, make the skin smooth like six year old kid, live more than 1,000 years and parasite diseases are not able to be of trouble.
Etymology
The plant's specific name is derived from Latin mirificus 'wonderful', 'miraculous'.
Uses
Some herbal supplements claim various health benefits of the extracts of Pueraria mirifica, although the claims are unsubstantiated and not backed by rigorous clinical evidence.
Pueraria mirifica contains various phytoestrogens, including deoxymiroestrol, daidzin, daidzein, genistin, genistein, coumestrol, kwakhurin, and mirificine, β-sitosterol, stigmasterol, campesterol, and mirificoumestan. There is contradictory evidence for the presence of miroestrol. Pueraria contains the cytotoxic non-phytoestrogen spinasterol.
Adverse effects
The safety of using P. mirifica extracts has not been adequately demonstrated, particularly for endocrine and reproductive functions, with adverse effects possibly affecting people having elevated blood lipids, asthma, diabetes mellitus,epilepsy or systemic lupus erythematosus. Women under 18 years old, those using birth control or prescription estrogen, and pregnant or nursing mothers should not use pueraria products.
National regulations
Due to inadequate evidence of safety and uncertainty about doses, several countries recommend against the use of pueraria products, have issued risk warnings, or have restricted their use in manufactured foods. Because pueraria extract does not have novel food approval in the European Union, it was banned as a food ingredient in Finland in 2009.