Claim: Putting sliced onion in the sole can repair blood circulation.

Rating: FALSE

Why we fact-checked this: The claim was spotted on Claim Check. The post containing the claim has over 116 reactions and 146 shares on Facebook, as of writing.

The bottom line: Although onions are rich in antioxidants and other vitamins such as vitamin C, there is no scientific evidence that shows putting onion in the sole can improve blood circulation. 

Why it doesn’t work: The chemical components of the onion with health benefits will not be absorbed by the body and will just be blocked by the skin because the main function of the skin is to keep substances out of the body.

• Also, the soles of the feet are one of the thickest parts of the skin in the body, with an additional layer called stratum lucidum, making it even more difficult to penetrate than other parts of the skin.

How to get onion’s health benefits: Health website Healthline said that onions need to be ingested in order for the antioxidants it contains to help boost the body’s blood circulation. A study where 23 men constantly take onion extract for 30 days showed that it significantly improved blood flow after meals.– Lorenz Pasion/Rappler.com

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