Red onions pack a cancer-fighting punch

Onions as a superfood are still not well known. But they contain one of the highest concentrations of quercetin, a type of flavonoid.

A new study revealed that the red onion not only has high levels of quercetin, but also high amounts of anthocyanin, which enriches the scavenging properties of quercetin molecules.

Anthocyanin is instrumental in providing colour to fruits and vegetables so it makes sense that the red onions, which are darkest in colour, would have the most cancer-fighting power.

Published recently in Food Research International, the study involved placing colon cancer cells in direct contact with quercetin extracted from the five different onion varieties.

"We found onions are excellent at killing cancer cells," said the lead author. "Onions activate pathways that encourage cancer cells to undergo cell death. They promote an unfavourable environment for cancer cells and they disrupt communication between cancer cells, which inhibits growth."

The researchers have also recently determined onions are effective at killing breast cancer cells.