Sunday Feb 15, 2015 (foodconsumer.org) -- High fat diet is known to induce obesity.  A new study led by H.W. Gil at Soonchunhyang University Cheonan Hospital in Cheonan, Korea  and colleagues suggests that Dioscorea batatas extract may be used as a dietary supplement to prevent obesity induced by a high fat diet such as the Western diet.

Dioscorea batatas or Dioscorea opposita is also known as Chinese Yam or Korean Yam.  In Chinese, it is called huái shan or shan yào.  The tuber of this plant is used to treat many health conditions.

The study conducted in mice shows that mice fed a high fat diet but also supplemented with a Dioscorea batatas extract for 14 weeks were found to have reduced visceral fact accumulation and obesity related biomarkers, compared to mice fed the same high fat diet only.

The study compared four diets, a normal diet, a high fat diet, the high fat diet with 100 mg of Dioscorea batatas extract per kg and the high fat diet with 200 mg of the extract per kg.

Supplementation of the diet with the extract for 14 weeks substantially reduced high fat diet induced increases in body weight, visceral adipose tissue, serum lipid concentrations and leptins.

The researchers found that the Dioscorea batatas extract downregulates "the adipogenic transcription factor (C/ERBa) and its target gene (CD36) in epididymal adipose tissue". 

Also the Dioscorea batatas extract was found to decrease the serum concentration of proinflammatory cytokines such as TNF-α, MCP-1, and IL-6 in epididymal adipose tissue.

The study concluded Dioscorea batatas extract may prevent high fat diet -induced obesity by downregulating the expression of genes involved in adipogenesis and inflammation in visceral adipose tissue.

The Chinese yam is used as a herb to treat tiredness, weight loss, poor appetite, poor digestion, chronic diarrhea, asthma, dry coughs, diabetes mellitus and emotional instability.  It is also used to treat external ulcers, boils and abscesses because of its healing effect and hyperthyroidism, nephritis and diabetes among others. (David Liu, PHD) (photo credit: wikipedia.org)

Gil HW, Lee EY, Lee JH, Kim YS, Lee BE, Suk JW, Song HY.  Dioscorea batatas Extract Attenuates High-Fat Diet-Induced Obesity in Mice by Decreasing Expression of Inflammatory Cytokines.  Med Sci Monit. 2015 Feb 14;21:489-495.