Notable sources of natural phenols in human nutrition include berries, tea, beer, olive oil, chocolate or cocoa, coffee, pomegranates, popcorn, yerba maté, fruits and fruit based drinks (including cider, wine and vinegar) and vegetables. Herbs and spices, nuts (walnuts, peanut) and algae are also potentially significant for supplying certain natural phenols.
Natural phenols can also be found in fatty matrices like olive oil. Unfiltered olive oil has the higher levels of phenols, or polar phenols that form a complex phenol-protein complex.
Phenolic compounds, when used in beverages, such as prune juice, have been shown to be helpful in the color and sensory components, such as alleviating bitterness.
Some advocates for organic farming claim that organically grown potatoes, oranges, and leaf vegetables have more phenolic compounds and these may provide antioxidant protection against heart disease and cancer. However, evidence on substantial differences between organic food and conventional food is insufficient to support claims that organic food is safer or healthier than conventional food.