Antioxidants and Their Role in Health
Let Food Be Your Medicine, and Medicine Be Your Food: Scientific Insights into the Healing Power of Nutrition, NOVA Publications , ss.81-103, 2026
- Yayın Türü: Kitapta Bölüm / Araştırma Kitabı
- Basım Tarihi: 2026
- Yayınevi: NOVA Publications
- Sayfa Sayıları: ss.81-103
- Anahtar Kelimeler: antioxidants, chronic diseases, dietary bioactive compounds, oxidative stress, reactive oxygen species (ROS)
- Sağlık Bilimleri Üniversitesi Adresli: Evet
Özet
This chapter provides a comprehensive overview of the role of oxidative stress and antioxidants in human health. The discussion begins with the definition and generation of reactive oxygen species (ROS) and free radicals, which are produced both endogenously during normal metabolic processes and exogenously through factors such as ultraviolet radiation, environmental pollution, smoking, alcohol consumption, and stress. Excessive ROS production leads to oxidative stress, causing cellular damage to DNA, proteins, and lipids, and is implicated in the pathogenesis of chronic diseases including cancer, cardiovascular disorders, neurodegeneration, and metabolic dysfunctions. The chapter emphasizes the mechanisms of antioxidants, distinguishing between endogenous enzymatic antioxidants (such as superoxide dismutase, catalase, and glutathione peroxidase) and non-enzymatic antioxidants (bilirubin, albumin, glutathione, etc.), as well as exogenous antioxidants derived from diet. Dietary antioxidants, including vitamins A, C, and E, selenium, zinc, carotenoids, flavonoids, and polyphenols, are highlighted for their ability to neutralize ROS, reduce oxidative damage, and support immune and metabolic health. Special attention is given to bioactive compounds such as quercetin, curcumin, resveratrol, beta-carotene, and lycopene, which have demonstrated strong antioxidant, anti-inflammatory, anticarcinogenic, and cardioprotective properties in both experimental and clinical studies. Their synergistic effects, such as the combined activity of vitamin C and flavonoids, are shown to enhance bioavailability and biological effectiveness. Clinical evidence is reviewed, including trials linking antioxidant intake with reduced risks of cardiovascular disease, cognitive decline, and oxidative stress-related complications. The chapter also examines the paradox of antioxidant supplementation, noting that while diets rich in fruits and vegetables consistently reduce disease risk, isolated antioxidant supplements often yield inconsistent or limited results in large-scale trials. This underscores the importance of whole dietary patterns rather than single-compound supplementation.