Apple polyphenols are standout nutrients in this widely loved fruit. These polyphenols include flavonols (especially quercetin, but also kaempferol and myricetin), catechins (especially epicatechin), anthocyanins (if the apples are red-skinned), chlorogenic acid, phloridizin, and several dozen more health-supportive polyphenol nutrients. Apple is a good source of fiber, including both soluble and insoluble pectins, and it’s also a good source of vitamin C. Apple nutrients are disproportionately present in the skin, which is a particularly valuable part of the fruit with respect to its nutrient content.