I love a good tea, so when I was served some steeped jiao gu lan or Gynostemma pentaphyllum at a Harmonic Arts training I did at work a few months back the slightly sweet, earthy tannins of this particular herb stuck with me until I shelled out a couple dollars to buy some of my own.
irst and foremost, I liked it for the taste. I like a savoury tea, if you know what I meant - I would drink plain green or black tea all day, if it weren’t for the caffeine. Gynostemma is for me, the perfect substitute. It's neither too flowery nor too much like, well, grass; it's the kind of tea I want to drink all day. Given the circumstances in which I first tried it (again, that was with Harmonic Arts - by far one of the most impressive and exciting smaller herb companies I've had the pleasure of getting to know - check them out!*), I knew there had to be some health benefits attached to it as well so I set about doing a bit of investigating.
TCM Actions for Gynostemma pentaphyllum
Gynostemma is a vining five-leaved tonifying herb that can be found growing in China, Korea and Japan. According to traditional Chinese medicine (TCM), it has slightly bitter and cold properties and enters through the Lung/Heart channels (Chen, 2002). It doesn’t have as rich a history in TCM as some other great tonics and Acupuncture Today says is a result of a changing pathology profile in today’s culture vs. ancient China as the herb a more relevant choice in the treatment of chronic versus infectious diseases.
Research has also been done on conventional applications for western conditions, which have shown the herb to be a useful daily tonic for metabolic disturbances. A recent study from Huyen et al. (2013) in the Journal of Nutrition and Metabolism used drug naive type 2 diabetic patients and showed that 4 weeks of consuming 6 g of Gynostemma or a placebo tea daily resulted in a decrease in fasting plasma glucose and steady-state plasma glucose in the Gynostemma group as compared to the placebo treatment (p < 0.001). This effect on fasting plasma glucose was also reversed after the treatments were exchanged following a two week wash out period. These improvements were achieved without a change in circulating insulin levels, lipids, body measurement, blood pressure or any reported hypoglycemia, leading the researchers to conclude that Gynostemma actually improved insulin sensitivity.
A 2012 animal study from Qin et al. showed that saponins extracted from Gynostemma given to rats fed a high-fat, high-cholesterol, high-alcohol diet, had a protective effect against liver fatty degenration in fatty liver disease as compared to a control group. Specific results indicated that the mechanism of action involved modulating lipid metabolism, ameliorating liver dysfunction and reducing oxidative stress. Another animal study from Ge et al. (2011), showed that gypenosides (as the Gynostemma saponins are called) may also have a protective effect on the heart in diabetics at risk for diabetic cardiomyopathy.
So if you are in the market for a new tea, are aware that you have some insulin resistance or just love a good tonifying herb - try Gynostemma. This is the the one I like but there are probably other great sources as well.
* Disclosure: I don't work for Harmonic Arts. I really just like them so much.
Chen, J. Gynostemma: An undiscovered treasure. Acupuncture Today. 2002;3(9)
Ge M, Ma S, Tao L, Guan S. The effect of gypenosides on cardiac function and expression of cytoskeletal genes of myocardium in diabetic cardiomyopathy rats. Am J Chin Med. 2009; 37(6):1059-68
Huyen VT, Phan DV, Thang P, Hoa NK, Ostenson CG. Gynostemma pentaphyllum tea improves insulin sensitivity in type 2 diabetic patients. J Nutr Metab. 2013;2013:765383. doi: 10.1155/2013/765383. Epub 2013 Jan 31.
Qin R, Zhang J, Li C, Zhang X, Xiong A, Huang F, Yin Z, Li K, Qin W, Chen M, Zhang S, Liang L, Zhang H, Nie H, Ye W. Protective effects of gypenosides against fatty liver disease induced by high fat and cholesterol diet and alcohol in rats. Arch Pharm Res. 2012 Jul; 35(7)1241-50