Strong-flavored onions may not help your social life but they could have significant potential for fighting cancer, report US researchers. Researchers have known for some time that onions may help fight cancer, but the current study is believed to be the first to compare cancer-fighting abilities among commonly consumed onion varieties. Preliminary laboratory studies by a team from Cornell University found members of the onion family with the strongest flavour -- particularly New York Bold, Western Yellow and shallots -- are the best varieties for inhibiting the growth of liver and colon cancer cells.