Red onions contain cancer-fighting properties

Love them or hate them, onions are quite the versatile plant. It can be fried, as a topping on pizza, and is often considered a vital ingredient in tomato sauces. Onions are known to make us cry when we cut them, but according to new research, the tears may be worth it.

Researchers from the University of Guelph, Canada, have found that Ontario-grown red onions are effective at fighting cancer cells.

Onions are a superfood

Considered a superfood, onions are known for having quercetin, a type of flavonoid—plant chemicals that hold powerful antioxidants with anti-inflammatory and immune system benefits.

Previous studies have found that quercetin has promising potential for preventing and controlling the formation of intestinal polyps, suppressing rhinoviruses (a source of the common cold), and even inhibiting cold sore development.

Cancer-fighting ingredients

The researchers tested five different types of onions grown in Ontario, Canada, and found that the ruby red onion variety contained the highest amounts of beneficial flavonoids. They also found that onions grown in Ontario boast particularly high levels of these compounds compared to other parts of the world.

Another flavonoid found in high amounts was anthocyanin. It acts much in the same manner as quercetin, working together to increase its powerful effect.

Part of the team’s research involved putting colon cancer cells in direct contact with quercetin extracted from the five different onions tested.

“We found onions are excellent at killing cancer cells. Onions activate pathways that encourage cancer cells to undergo cell death. They promote an unfavorable environment for cancer cells and they disrupt communication between cancer cells, which inhibits growth,” said Abdulmonem Murayyan, a Ph.D. student at Guelph University.
This cancer-fighting effect was also effective for killing breast cancer cells.

Using advanced techniques

The researchers are using a new extraction method to obtain the flavonoids. Previous methods utilized chemical solvents that could leave a toxic residue. This new method of extraction eliminates this, making the quercetin found in onions more suitable for consumption.

“This new method that we tested to be effective only uses super-heated water in a pressurized container. 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,” said Murayyan.

Quercetin is expected to be incorporated into products in the future, such as juice and baked goods, with a pill form in the works. Until then, you can get this superfood any time at your local grocery store.