What is the role of antioxidants in health?
Pro Research Analysisby 
Searched over 200M research papers
The Role of Antioxidants in Health
Introduction to Antioxidants and Free Radicals
Antioxidants are compounds that inhibit the oxidation of other molecules, thereby protecting the body from the harmful effects of free radicals. Free radicals, such as reactive oxygen species (ROS) and reactive nitrogen species (RNS), are produced during normal cellular metabolism and can cause damage to DNA, lipids, proteins, and other biomolecules if not adequately neutralized1 4 5. The body's endogenous antioxidant defenses, including enzymes like superoxide dismutase (SOD) and catalase (CAT), are often insufficient to prevent oxidative damage completely, making dietary antioxidants crucial for maintaining health1 5.
Dietary Antioxidants and Their Sources
Dietary antioxidants are found in various fruits, vegetables, seeds, and other natural products. Key antioxidants include vitamins E and C, carotenoids, flavonoids, and other plant phenolics1 3 5. These compounds are known for their ability to scavenge free radicals, thereby reducing oxidative stress and protecting cellular components from damage1 3 5. The consumption of antioxidant-rich foods has been linked to a reduced risk of chronic diseases such as cardiovascular disease, cancer, and neurodegenerative disorders3 9 10.
Mechanisms of Antioxidant Action
Antioxidants neutralize free radicals through various mechanisms, including direct scavenging of reactive species, chelation of metal ions, and modulation of antioxidant enzyme activity1 5 8. For instance, vitamin C can donate electrons to neutralize free radicals, while flavonoids can chelate metal ions that catalyze oxidative reactions1 5 8. Additionally, some antioxidants can activate signaling pathways that enhance the body's endogenous antioxidant defenses, further contributing to their protective effects6 8.
Paradoxical Roles of Antioxidants
While antioxidants are generally considered beneficial, their effects can be context-dependent. In some cases, antioxidants can exhibit prooxidant behavior, potentially leading to adverse outcomes2. For example, overexpression of antioxidant enzymes in certain physiological contexts can promote disease rather than prevent it2. This paradox highlights the complexity of redox biology and the need for a nuanced understanding of antioxidant function in health and disease2.
Antioxidants and Immune Function
Antioxidants play a significant role in modulating immune function. They help regulate the production of ROS during inflammatory responses, which is crucial for defending against pathogens9. Nutrients like vitamin E, vitamin C, and selenium are known to enhance immune cell function and protect against infections9. However, excessive intake of antioxidants can suppress certain immune responses, potentially leading to increased susceptibility to infections and other immune-related issues6 9.
Conclusion
Antioxidants are vital for protecting the body against oxidative stress and maintaining overall health. They are found in various dietary sources and work through multiple mechanisms to neutralize free radicals and support immune function. However, the role of antioxidants is complex, and their effects can vary depending on the physiological context. A balanced intake of antioxidants through a diet rich in fruits and vegetables is essential for optimizing health and preventing chronic diseases.
Sources and full results
Most relevant research papers on this topic
Antioxidants in human health and disease.
Antioxidants, particularly vitamins E and C, are crucial for maintaining human health and preventing damage from reactive oxygen and nitrogen species.
Highly CitedParadoxical Roles of Antioxidant Enzymes: Basic Mechanisms and Health Implications.
Antioxidant enzymes can play both health-protective and disease-promoting roles, and viewing them as always beneficial is misleading and potentially dangerous for medical treatment protocols.
Highly CitedNatural antioxidants from some fruits, seeds, foods, natural products, and associated health benefits: An update
Natural antioxidants found in fruits, seeds, foods, and natural products have various health-promoting effects, improving free radical disease management without the toxicities and side effects of conventional medications.
Systematic ReviewHighly CitedAntioxidants in health and disease
Antioxidants prevent free radical-induced tissue damage, which can contribute to diseases like atherosclerosis, by preventing their formation, scavenging them, or promoting their decomposition.
Highly CitedUnderstanding oxidants and antioxidants: Classical team with new players.
Antioxidants and probiotics in fortified foods and supplements help protect cells from oxidative stress and damage, which can contribute to various diseases.
Highly CitedThe good and bad of antioxidant foods: An immunological perspective.
Antioxidant foods may have both beneficial and harmful effects on immune responses, and excessive intake may suppress type 1 immune responses and increase Th2 reactions.
The characterization of antioxidants.
Antioxidants are used in nutrition to prolong shelf life and maintain nutritional quality of lipid-containing foods, and to modulate oxidative damage in the human body.
Highly CitedMechanisms of Plant Antioxidants Action
Plant antioxidants promote human health by counteracting reactive oxygen/nitrogen species, modulating plant growth, and providing defense against pathogens and predators.
Rigorous JournalDietary antioxidants: immunity and host defense.
Dietary antioxidants, such as vitamin E, vitamin C, -carotene, selenium, copper, iron, and zinc, improve immune function and host resistance to infectious microorganisms.
Highly CitedAntioxidant-rich natural fruit and vegetable products and human health
Antioxidants in fruits and vegetables can reduce the risk of chronic human diseases by improving human health as nutraceuticals, pharmaceuticals, and phytoceuticals.
Highly CitedTry another search
What is the role of artificial intelligence in enhancing the efficiency and accuracy of scientific research?
Where does lightning come from?
Why do we have to wear sunscreen?
What is the Smart cities and citizen privacy?
What people can do with solar radiation
What are the strategies for addressing the social and ethical implications of technological unemployment?