Plant flavonoids in health, prevention, and treatment of chronic diseases

Abstract

Noncommunicable diseases (NCDs), also known as chronic diseases, principally cardiovascular disease (CVDs), diabetes, neurodegenerative diseases, and cancer, continue to be a burden for health systems in both developed and developing countries. NCDs and their complications are responsible for an increased number of deaths and expensive medical costs. These and other factors make the prevention of NCDs an extremely high priority for clinical medicine and public health. Flavonoids are a group of bioactive compounds that are widely distributed in many plant-based foods and beverages. Epidemiological studies support the important role of high flavonoid intake in the prevention of a number of NCDs, including type 2 diabetes mellitus, CVDs, cataract, neurodegenerative disorders, and cancer. Moreover, in vitro and animal studies report important roles of flavonoids such as quercetin, kaempferol, naringenin, hesperitin, and luteolin, in the treatment of cardiovascular and neurodegenerative diseases and also cancer. Dietary flavonoids exert their cardioprotective effects by regulating blood pressure, protecting against oxidized low-density lipoprotein induced damage, and providing antiplatelet effects. Furthermore, they may protect the nervous system through the reduction of neuroinflammation and axonal damage. Anticancer actions of flavonoids depend on their ability to inactivate carcinogens and to enhance DNA repair processes. Flavonoids exert antioxidative and anti-inflammatory effects through their free radical scavenging properties; therefore, they play important roles in the prevention of metabolic abnormalities such as dyslipidemia, insulin resistance, hypertension, glucose intolerance, inflammation, and oxidative stress. There is a growing body of evidence that diets rich in flavonoids are beneficial for improved health and prevention of NCDs.