Onions contain antioxidants and compounds that fight inflammation, decrease triglycerides and reduce cholesterol levels — all of which may lower heart disease risk. Their potent anti-inflammatory properties may also help reduce high blood pressure and protect against blood clots.

Side effects might include stomach distress or pain after eating onion. When applied to the skin: Onion extract is LIKELY SAFE when applied to the skin. Side effects might include skin irritation or eczema following skin contact with onion.