Recipes often call for just “onions” without specifying the type, and it’s easy to default to plain old white or yellow ones. But is that the right choice for your health?
Turns out, there’s one variety of onions that’s better for you than the others. A 2017 study published in Food Research International found that red onions were most effective at killing human cancer cells compared with other onions thanks to their higher levels of the antioxidants quercetin and anthocyanin.
“Anthocyanin is instrumental in providing color to fruits and vegetables, so it makes sense that the red onions, which are darkest in color, would have the most cancer-fighting power,” says study author Suresh Neethirajan, Ph.D.
However, red onions aren’t the only ones with these benefits. “All onions are potent cancer fighters thanks to their high concentrations of the antioxidants anthocyanin and quercetin,” says Karen Ansel R.D.N., author of Healing Superfoods for Anti-aging: Stay Younger, Live Longer. Red onions just happen to be even better at fighting cancer thanks to their high amounts of anthocyanin, which increase the effectiveness of quercetin in attacking cancer-causing free radicals, she adds.
Luckily, red onions swap in easily in place of white. Try substituting the colorful variety anytime your usual recipes call for white or yellow onions for an extra boost of powerful antioxidants (and flavor).