Toronto: Eating red onions may help fight cancer, say scientists including one of Indian origin, paving the way for a natural pill that can treat the deadly disease.
Onions activate pathways that encourage cancer cells to undergo cell death. They promote an unfavourable environment for cancer cells and disrupt communication between cancer them, which inhibits growth, researchers from University of Guelph in Canada said.
Onions as a superfood are still not well known. They contain one of the highest concentrations of quercetin, a type of flavonoid, they said.
The team found that red onions not only have high levels of quercetin, but also high amounts of anthocyanin, which enriches the scavenging properties of quercetin molecules.
"We found onions are excellent at killing cancer cells," said Abdulmonem Murayyan, post doctoral student at University of Guelph.
The team tested five onion types grown in Ontario and discovered that the Ruby Ring onion variety - that has hard, firm, tall globe-shaped bulbs with dark red colour features - has the strongest cancer-fighting power.
"The next step will be to test the vegetable's cancer- fighting powers in human trials," said Murayyan.
These findings follow a recent study by the researchers on new extraction technique that eliminates the use of chemicals, making the quercetin found in onions more suitable for consumption.
Other extraction methods use solvents that can leave a toxic residue which is then ingested in food, said Suresh Neethirajan, professor at University of Guelph.
"This new method that we tested to be effective only uses super-heated water in a pressurised container," he said.
"Developing a chemical-free extraction method is important because it means we can use onion's cancer-fighting properties in nutraceuticals and in pill form," he added.
While we can currently include this superfood in salads and on burgers as a preventative measure, the researchers expect onion extract will eventually be added to food products such as juice or baked goods and be sold in pill form as a type of natural cancer treatment.
The study was published in the journal Food Research International....