Flavonoids are plant antioxidants found in various parts of plants. They are usually attached to sugars, but can also exist without them. When released from sugars, they combine with other molecules for easier removal from the body. Flavonoids are not well absorbed in the intestines and are quickly excreted through urine and bile. Different types of flavonoids have varying absorption rates, with gallic acid and isoflavones being absorbed the best. Quercetin is excreted slowly, while anthocyanins and catechins are excreted quickly. Understanding how flavonoids are absorbed and metabolized can help in creating effective intervention strategies.