Of all cases of food poisoning. The most common – leafy greens such as spinach, lettuce, and kale are at the highest risk. Make sure you purchase fresh greens. If they’re refrigerated, dig them out from the back of the shelf where it’s the coldest part of the coolers. Washing them will be of some benefit, and rinsing them with a fruit and vegetable wash that you can find at health food stores will also be of benefit.