Red wine has long been known to provide antioxidants along with research studies reporting improvements in cardiovascular markers. Another vegetable that provides antioxidants is the onion.
Throughout the world onion is one of the most consumed vegetables and is known to be high in flavonoids including quercetin (kwor-seh-tin).
This combination is popular in southeast Asia with reported benefits including hypertension, high cholesterol, diabetes, eye strain, and constipation,
A study out of Taiwan designed a study to determine if a red win extract of onion can affect the lipid profile, antioxidant status and inflammatory markers in healthy human subjects.
Twenty three human subjects were enrolled in the study and randomized to consume red wine or red wine onion extract.
To make a red wine onion extract fresh yellow onions were chopped and soaked in red wine, then ground up and filtered.
Subjects consumed 250 mL (about 8 ounces) of red wine or a red wine onion extract daily for 10 weeks, that’s 70 days.
In total, 11 of the 13 who consumed the red wine onion extract were able to finish the study with the 2 that dropped out complaining of an unpleasant flavor.
At the end of the study on average the following observations were noted with the red wine and onion extract:
- Total Cholesterol dropped from 217 to 205 mg/dL
- Triglycerides dropped from 155 to 126 mg/dL
- HDL stayed the same 52 to 52 mg/dL
- LDL dropped from 142 to 127 mg/dL
Antioxidant status was also evaluated:
- GSH increased 37 %
- GPx increased 15 %
- GR increased 245%
(GPx, glutathione peroxidase; GR, glutathione reductase; GSH, reduced glutathione)
Take away message: Damage from free radicals during a high cholesterol state may lead to toxic products that damage the blood vessels.
In this study each day the subjects consumed 42.5 mg of polyphenols from red wine along with an undetermined amount of antioxidants from onion was shown to reduce total cholesterol, LDL (i.e. the harmful cholesterol) and triglycerides along with improving antioxidant status.
Phytotherapy Research. 2016 March; Volume 30 (Issue 3): pages 380-5.
His research on plant medicine has led to more than 45 publications and abstracts.This research has been presented at international meetings in the USA, France, Turkey, Peru, Israel, Austria, and Italy.
Categories: Antioxidant, Cholesterol, Clinical Trials, Heart
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