The reason free radicals are highly unstable is that they have an unpaired electron which they try to recompense by stealing an electron from a stable molecule. This actually sets off a chain reaction that can damage the body's proteins and cell membranes, weaken the cell's natural defenses, and disrupt the cell's DNA. It would have been better if you only end up with thunder thighs after a bowl of rich cream, but there are far more serious health risks you'll have to consider when you indulge yourself with such things. That was then. This is now and it's perfectly okay to whip out your spoons, forks, and mats because today is decades in the making; today is the day you are permitted to salivate. There are several kinds of berries, as you well know, and each kind has a different concentration of antioxidants. In recent studies, purple berries (such as Elderberry and black currant) are considered as the richest antioxidant foods. However, raspberries, cranberries, blueberries, and blackberries are also good antioxidant foods that are rich in proanthocyanidins which help prevent cancer and heart disease. The human body derives its energy from the utilization of nutrients and oxygen as fuel. But oxygen, for all its benefits and positive effects, may also carry with it some negative ripple effect. When processing oxygen in the body (a process called "oxidation), oxygen byproducts are produced. These byproducts, called free radicals, are highly reactive substances that may cause damage to cells. Antioxidants are substances that work on free radicals, or more particularly work to counteract the damaging effects of these harmful oxygen byproducts. Scientists have linked free radicals to the development of degenerative diseases, causing massive cell damage that ultimately results in various disorders, such as cancer, Alzheimer's, Parkinson's, rheumatoid arthritis, atherosclerosis, heart disease, and much, much more. However, because of their high reactivity, free radicals often participate in unwanted side reactions resulting in cell damage. Many forms of cancer are thought to be the result of reactions between free radicals and DNA, resulting in mutations that can adversely affect the cell cycle and potentially lead to malignancy.