Some nutrients have antioxidant properties and can neutralize the potentially harmful effects of free radicals which are produced when food is broken down or when the body is exposed to certain environmental conditions such as cigarette smoke or radiation.
An imbalance between antioxidants and reactive oxygen species results in a condition called “oxidative stress” and is commonly implicated in chronic diseases such as cancer, heart disease, Alzheimer’s disease, rheumatoid arthritis, and many more.
Antioxidants are important because they can neutralize free radicals. Dietary antioxidants are vitamin A (more specifically, the precursor for vitamin A which is beta-carotene), vitamin C, vitamin E, zinc and selenium. However, recent studies have demonstrated that flavonoids found in fruits and vegetables may play their role in our antioxidant mechanisms.
Flavonoids are polyphenolic compounds present in all diets and are categorized, according to chemical structure, into flavonols, flavones, flavanones, isoflavones, catechins, anthocyanidins and chalcones. Over 4,000 flavonoids have been identified, many of which occur in fruits, vegetables and beverages (tea, coffee, beer, wine and fruit drinks).
They have antioxidant activity in vitro and affect cellular and molecular processes to provide health benefits by reducing the risk of chronic diseases.
Flavonoids may help provide protection against diseases by contributing, along with antioxidant vitamins and enzymes, to the total antioxidant defense system of the human body. Epidemiological studies have shown that flavonoid intake is inversely related to mortality from coronary heart disease and to the incidence of heart attacks.