What are antioxidants
Pro Research Analysisby 
Searched over 200M research papers
Understanding Antioxidants: Mechanisms, Sources, and Health Benefits
What Are Antioxidants?
Antioxidants are substances that can delay or prevent the oxidation of other molecules, thereby protecting cells from damage caused by free radicals and reactive oxygen species (ROS)1 2. These compounds act through various mechanisms, including hydrogen atom transfer (HAT), single electron transfer (SET), and metal chelation1. The primary role of antioxidants is to neutralize free radicals, which are unstable molecules that can cause cellular damage, leading to various diseases and aging3 4.
Mechanisms of Action
Hydrogen Atom Transfer (HAT) and Single Electron Transfer (SET)
Antioxidants can neutralize free radicals through HAT and SET mechanisms. In the HAT mechanism, antioxidants donate a hydrogen atom to free radicals, stabilizing them. In the SET mechanism, antioxidants donate an electron to free radicals, converting them into less reactive species1 6. These mechanisms are crucial for understanding how antioxidants function at a molecular level and their potential applications in health and disease prevention1.
Metal Chelation
Some antioxidants can chelate transition metals, preventing these metals from catalyzing the formation of free radicals. This is particularly important in biological systems where metal-catalyzed oxidation can lead to significant cellular damage1 7.
Sources of Antioxidants
Natural Sources
Antioxidants are abundant in various natural sources, including fruits, seeds, and other plant-based foods. Common natural antioxidants include vitamins C and E, carotenoids, flavonoids, and phenolic acids3 7. These compounds are known for their ability to scavenge free radicals and protect the body from oxidative stress3 4.
Synthetic Antioxidants
In addition to natural sources, antioxidants can also be synthesized. Synthetic antioxidants like butylated hydroxytoluene (BHT) and butylated hydroxyanisole (BHA) are commonly used in the food industry to prolong shelf life and maintain nutritional quality7. However, there is growing consumer concern regarding the safety of synthetic antioxidants, leading to increased interest in natural alternatives7.
Health Benefits
Prevention of Chronic Diseases
Antioxidants play a significant role in preventing chronic diseases such as cardiovascular diseases, cancer, and neurodegenerative disorders. They achieve this by neutralizing free radicals, thereby reducing oxidative stress and preventing cellular damage3 4 9. For instance, vitamins C and E have been shown to be effective in reducing oxidative damage and improving overall health4 9.
Anti-Aging Properties
Oxidative stress is a major contributor to the aging process. By neutralizing free radicals, antioxidants can slow down the aging process and reduce the risk of age-related diseases such as Alzheimer's and cataracts3 4.
Enhancing Immune Function
Antioxidants also play a crucial role in enhancing immune function. They protect immune cells from oxidative damage, thereby improving the body's ability to fight infections and diseases4 7.
Conclusion
Antioxidants are vital compounds that protect the body from oxidative stress and free radical damage. They act through various mechanisms, including hydrogen atom transfer, single electron transfer, and metal chelation. Found in both natural and synthetic forms, antioxidants offer numerous health benefits, including the prevention of chronic diseases, anti-aging properties, and enhanced immune function. Understanding the mechanisms and sources of antioxidants can help in making informed choices about diet and health supplements to improve overall well-being.
Sources and full results
Most relevant research papers on this topic
Antioxidant Compounds and Their Antioxidant Mechanism
Antioxidant compounds, such as polyphenols, carotenoids, and vitamins C, act through various chemical mechanisms to delay or prevent oxidation of substrates, aiding in understanding their biological meaning and potential uses.
Highly CitedAntioxidants: Differing Meanings in Food Science and Health Science.
Antioxidants in food science help maintain freshness and prolong shelf lives, while in health science they may quench reactive oxygen species and prevent chronic diseases, but strong evidence for their beneficial effects is lacking.
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 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 CitedThe 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 CitedIntracellular antioxidants: from chemical to biochemical mechanisms.
Intracellular antioxidants prevent free radical formation and play a crucial role in regulating protein expression and activity in aerobic cells.
Highly CitedNATURAL ANTIOXIDANTS: SOURCES, COMPOUNDS, MECHANISMS OF ACTION, AND POTENTIAL APPLICATIONS
Natural antioxidants, such as phenolic acids, flavonoids, and volatile oils, can effectively maintain the quality of ready-to-eat food products, offering a safer alternative to synthetic antioxidants.
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 CitedAntioxidants: Positive or Negative Actors?
Antioxidants may play a dual role in disease prevention and disease onset, but their ability to decrease pathologic reactive oxygen species is not clearly established.
Highly CitedRole of antioxidants in prophylaxis and therapy: A pharmaceutical perspective.
Novel drug delivery systems (NDDS) can improve the bioavailability and effectiveness of antioxidants for prophylaxis and therapy in various diseases.
Highly Cited