A grape as a source of resveratrol is not always the best choice. Grapes are one of the foods that serve as a source of resveratrol, especially muscadine grapes. You can find resveratrol in grape vines, grape roots, grape seeds, and grape stalks, but the highest concentration of resveratrol is found in the skin of grapes. The skin of grapes can contain anywhere from 50 to 100 micrograms per gram, which makes it a great source, but not the best source.
While many experts will say that grapes are one of the best sources to obtain resveratrol from, that is not the case; supplements are actually the best form of resveratrol. The reason that grapes and other foods are not the best source of resveratrol is because the amount of resveratrol is going to vary; you will never be able to get a consistent amount from any food source, including grapes. You cannot get the proper amount of resveratrol from foods because of the nutrient being damaged by oxygen and light, the damage lowers the concentration in the foods, which makes it even harder to measure.
It is important to get a consistent amount of resveratrol from any source because of the negative side effects of resveratrol, but also because of the benefits, that resveratrol provides. If you are not getting enough resveratrol, you are not going to experience the positive side effects. One of the main benefits to resveratrol is how effective it is against cancer. Resveratrol is one of the few antioxidants that targets more than one type of cancer. Resveratrol is effective against skin, prostate, and pancreatic cancer because it attacks the mitochondria of the cancer cells, which is the energy source for the cancer cells. Resveratrol also supports heart health because it improves your blood flow and prevents blockages in your arteries.
With all of these benefits and more it is important that you receive the maximum amount of resveratrol each day, you do not want to take more than 500 mg a day because of the chance of negative side effects of resveratrol. Since it is important to get a specified amount of resveratrol each day it is easiest just to take supplements, and add to that amount based on the foods that you eat, such as grapes. Taking the supplements guarantees that you will receive the desired amount of resveratrol, while eating foods like grapes, will just give you that much more of a benefit. Not to mention eating foods that are rich in resveratrol will not cause the side effects that the supplements will, so there is no need to worry about eating too many grapes.