Ginger extract may inhibit obesity, inflammation, suggests study on rats fed a high-fat diet
These were the results of a study conducted by researchers from South Korea, published recently in the journal Nutrients.
“[Ginger extract] would be useful for application as a functional food for the prevention of obesity and inflammation,” they argued.
“Our findings suggest that [ginger extract] inhibits body weight gain and adipose tissue in rats fed a high-fat diet” through the down-regulation of certain mRNA (a type of molecule conveying genetic information) related to the storing of fat, as well as biomarkers linked to inflammation.
They postulated that the improvements of markers linked to obesity and inflammation in rats supplemented with ginger extract, even though they were eating a high-fat diet, was due to the volatile oils (gingerols and shogaols) present, which give ginger its distinctive scent.
Two types of extracts were used in the study—high-hydrostatic pressure extract of ginger, as well as hot water extract of ginger, both supplied by the Korea Food Research Institute.
What is high-hydrostatic pressure extract of ginger?
High-hydrostatic pressure technology is a low-temperature extraction method “that does not destroy or denature the active substances by heat during the extraction process of various natural products,” the authors wrote.
For this study, the researchers bought ginger from a local market, added it in distilled water, and then pulverized it. This resulting puree was poured into plastic bags with an enzyme and then treated in a high-pressure vessel. The final step was to filter and freeze-dry the ginger.
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(Originally published Sept-21-2018)
Researchers compared the performance of high-hydrostatic pressure extracted ginger to a hot water extract, in which researchers heated the ginger at 100 degrees Celsius for three hours, before then freeze-drying the ginger.
Results: Pressure technology fared better than hot water extract
At the end of the study, rats supplemented with ginger extracted using high-hydrostatic pressure had lower body weight and white adipose mass compared to the rats fed only a high-fat diet.
In most of the evaluated outcomes, both ginger extracts were linked to an improvement, but rats supplemented with the high-hydrostatic pressure extract exhibited better improvements in gene activity and weight gain inhibition that the hot water extract group.
The researchers evaluated levels of genes and proteins that are related to how the body stores fat and suffers inflammation, specifically after the body has gone through changes caused by following a high-fat diet.
Twenty-seven rats were used. They were divided into three groups (nine in each) and fed either a high-fat diet, a high-fat diet containing ginger extracted using hot water, or a high-fat diet containing ginger extracted with high-hydrostatic pressure.
This diet period lasted for 10 weeks, during which researchers measured body weight and food intake twice a week using a digital scale.
At the end of the study, rats were euthanized so that the researchers can look at serum, liver, and epididymal adipose tissue.
The exact mechanism is still unclear, so further studies are still needed, the researchers wrote.
Published online, doi:10.3390/nu10111567
“Ginger Extract Ameliorates Obesity and Inflammation via Regulating MicroRNA-21/132 Expression and AMPK Activation in White Adipose Tissue”
Authors: Seunghae Kim, et al