Orange seeds are edible. Though the seeds of citrus fruits, such as oranges, lemons and tangerines, contain small amounts of cyanide compounds, a typical orange's seeds do not contain enough of the toxin to be harmful.
Orange seeds can be blended in smoothies, but it is best not to eat them in large quantities. Tangerine seeds are very bitter because they have a higher amount of the cyanide toxin. Though fruit seeds have some fabled medical properties, there is no scientific evidence to support the claim that fruit seeds cure cancer. Many varieties of oranges are seedless, including clementines, navel oranges and satsumas.