Onions

Peak Season: Year-round

Perfect Pick: Nicely shaped with no swelling at the neck and dry, crisp outer skin. Lackluster onions have soft spots, green sprouts, or dark patches.

Handle with Care: Keep onions in a cool, dark location away from potatoes for 3 to 4 weeks.

The Payoff: GPCS, a peptide shown to reduce bone loss in rates, plus the cancer-fighting compound quercetin.