--- title: "Oxidative Stress Definition & Meaning | infoMD Health Glossary" description: "Oxidative stress is a condition that occurs when the production of reactive oxygen species (free radicals) exceeds the body's ability to neutralize them wi" lang: en json-ld: | [ { "@context": "https://schema.org", "@type": "DefinedTerm", "name": "Oxidative Stress", "description": "Oxidative stress is a condition that occurs when the production of reactive oxygen species (free radicals) exceeds the body's ability to neutralize them with antioxidant defenses, resulting in cellular damage. Free radicals are unstable molecules produced naturally during metabolism and energy production, but also generated in excess by external factors like pollution, UV radiation, smoking, alcohol, and processed foods. When antioxidants can't keep up, these aggressive molecules damage proteins, lipids, and DNA.", "inDefinedTermSet": { "@type": "DefinedTermSet", "name": "infoMD Health Glossary", "url": "https://infomd.com/glossary" }, "url": "https://infomd.com/glossary/oxidative-stress" }, { "@context": "https://schema.org", "@type": "BreadcrumbList", "itemListElement": [ { "@type": "ListItem", "position": 1, "name": "Home", "item": "https://infomd.com" }, { "@type": "ListItem", "position": 2, "name": "Glossary", "item": "https://infomd.com/glossary" }, { "@type": "ListItem", "position": 3, "name": "Oxidative Stress", "item": "https://infomd.com/glossary/oxidative-stress" } ] } ] --- [Skip to main content](#main-content) [![infoMD](/assets/infomd-logo-CtvTblFD.png)](/) [Home](/) [Conditions](/conditions) [Glossary](/glossary)[Shop](/shop) 1. [Home](/) 2. [Glossary](/glossary) 3. Oxidative Stress [General Health]() # Oxidative Stress ox·i·da·tive stress - OK-sih-day-tiv stres ## Definition Oxidative stress is a condition that occurs when the production of reactive oxygen species ([free radicals](/glossary/free-radicals)) exceeds the body's ability to neutralize them with antioxidant defenses, resulting in cellular damage. Free radicals are unstable molecules produced naturally during [metabolism](/glossary/metabolism) and energy production, but also generated in excess by external factors like pollution, UV radiation, smoking, alcohol, and processed foods. When antioxidants can't keep up, these aggressive molecules damage proteins, [lipids](/glossary/lipids), and DNA. The body maintains an elaborate antioxidant defense system that includes internally produced [enzymes](/glossary/enzyme) (superoxide dismutase, catalase, glutathione peroxidase) and dietary antioxidants (vitamins C and E, beta-carotene, selenium, polyphenols, and flavonoids). Under normal conditions, this system keeps free radicals in check and even uses them for beneficial purposes like immune defense and cell signaling. Oxidative stress occurs when this balance tips toward oxidant overproduction or antioxidant depletion. Cumulative oxidative damage is now considered a fundamental mechanism underlying aging and virtually every major chronic disease. It damages the endothelial lining of blood vessels (promoting [atherosclerosis](/glossary/atherosclerosis)), causes DNA mutations (promoting cancer), destroys neurons (promoting neurodegeneration), impairs insulin signaling (promoting diabetes), and degrades [collagen](/glossary/collagen) and elastin (promoting skin aging). This makes oxidative stress management - through diet, lifestyle, and minimizing toxic exposures - a cornerstone of preventive health. ## Also Known As Oxidant stress Redox imbalance ## Key Facts - • Oxidative stress is implicated in cardiovascular disease, cancer, neurodegenerative diseases, diabetes, and the aging process itself. - • The body's primary internal antioxidants are superoxide dismutase (SOD), catalase, and glutathione - the 'master antioxidant.' - • Foods highest in antioxidants include berries, dark chocolate, pecans, artichokes, kidney beans, and green tea. - • Moderate exercise reduces oxidative stress over time by upregulating antioxidant enzyme systems, despite acutely increasing free radical production. - • Megadose antioxidant supplements have not shown the same benefits as dietary antioxidants and may interfere with beneficial oxidant signaling. ## How It Relates To Your Health Oxidative stress is measurable through biomarkers including malondialdehyde (MDA), F2-isoprostanes, 8-OHdG, and oxidized LDL. While these markers are used primarily in research settings, they are increasingly available through [functional medicine](/glossary/functional-medicine) labs for clinical assessment of oxidative burden. The most evidence-based approach to managing oxidative stress is through lifestyle: eating a colorful, plant-rich diet that provides diverse antioxidants in their natural matrix; exercising regularly; avoiding smoking and excessive alcohol; protecting skin from UV radiation; minimizing exposure to environmental pollutants; managing chronic stress; and getting adequate sleep. These practices support both internal antioxidant production and dietary antioxidant intake. ## Related Terms [Free Radicals](/glossary/free-radicals)[Anti-inflammatory](/glossary/anti-inflammatory)[Mitochondria](/glossary/mitochondria)[Chronic Inflammation](/glossary/chronic-inflammation)[Phytonutrients](/glossary/phytonutrients) ## Related Articles [![The Mediterranean Diet: A Complete Beginner's Guide](https://images.unsplash.com/photo-1498837167922-ddd27525d352?w=1200&h=630&fit=crop&fm=webp)](/nutrition/mediterranean-diet-beginners-guide) [](/nutrition/mediterranean-diet-beginners-guide)[Nutrition & Diet](/nutrition) ### The Mediterranean Diet: A Complete Beginner's Guide 2026-01-20 [![The Science Behind Cold Plunge Therapy](https://images.unsplash.com/photo-1544367567-0f2fcb009e0b?w=1200&h=630&fit=crop&fm=webp)](/wellness/science-behind-cold-plunge) [](/wellness/science-behind-cold-plunge)[Wellness](/wellness) ### The Science Behind Cold Plunge Therapy 2026-02-12 ## Sources 1. [Oxidative Stress](https://www.ncbi.nlm.nih.gov/books/NBK556034/) - StatPearls / PubMed 2. [Antioxidants: In Depth](https://www.nccih.nih.gov/health/antioxidants-in-depth) - National Center for Complementary and Integrative Health (NIH) 3. [Oxidative Stress and Human Health](https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3614697/) - National Library of Medicine Was this definition helpful? In This Entry [Definition](#definition)[Also Known As](#also-known-as)[Key Facts](#key-facts)[How It Relates To Your Health](#health-relevance)[Related Terms](#related-terms)[Related Articles](#related-articles)[Sources](#sources) Browse General Health Terms [Biomarker](/glossary/biomarker)[BMI](/glossary/bmi)[Epigenetics](/glossary/epigenetics)[Free Radicals](/glossary/free-radicals)[Functional Medicine](/glossary/functional-medicine)[Homeostasis](/glossary/homeostasis) Advertisement #### Explore - [Condition Library](/conditions) - [Health Glossary](/glossary) - [Shop](/shop) #### Body Systems - [Cardiovascular](/conditions/body-system/cardiovascular) - [Digestive](/conditions/body-system/digestive) - [Neurological](/conditions/body-system/neurological) - [Respiratory](/conditions/body-system/respiratory) - [Musculoskeletal](/conditions/body-system/musculoskeletal) - [Endocrine](/conditions/body-system/endocrine) - [Immune System](/conditions/body-system/immune-system) - [Mental Health](/conditions/body-system/mental-health) - [Skin](/conditions/body-system/skin) #### Company - [About infoMD](/about) - [Contact Us](/contact) - [844-357-3601](tel:+18443573601) #### Legal - [Privacy Policy](/privacy-policy) - [Terms of Use](/terms-of-use) - [Disclaimer](/disclaimer) - [Cookie Policy](/cookie-policy) - [Accessibility](/accessibility) © 2026 infoMD LLC. All rights reserved. For informational purposes only. See our [Disclaimer](/disclaimer). [About](/about)[Contact](/contact)[Privacy Policy](/privacy-policy)[Terms of Use](/terms-of-use)