free radical

Definition of free radical

: an especially reactive atom or group of atoms that has one or more unpaired electrons especially : one that is produced in the body by natural biological processes or introduced from an outside source (such as tobacco smoke, toxins, or pollutants) and that can damage cells, proteins, and DNA by altering their chemical structure

Examples of free radical in a Sentence

Recent Examples on the Web In a nutshell, oxidative stress occurs when there is an imbalance between the production of cell-damaging free radicals and the body's ability to counter their harmful effects, which include premature aging and disease risk. — Cynthia Sass, Mph, Health.com, "Cauliflower Benefits: 7 Ways This Vegetable Helps Your Health," 23 Oct. 2019 Antioxidants are substances that neutralize free radicals — unstable oxygen molecules that break down skin cells and cause wrinkles. — Mayo Clinic News Network, chicagotribune.com, "Home remedies: Weathering those wrinkles," 25 Oct. 2019 These compounds are known to help keep inflammation low by neutralizing free radicals—which can cause cell damage that in turn can lead to chronic disease such as heart disease and cancer. — Julie Upton, Health.com, "Pear Nutrition: 5 Ways This Fruit Can Boost Your Health," 24 Oct. 2019 And we are told that antioxidants in superfoods and beauty products will mop up free radicals, protecting us from their aging effects and keeping us young and disease-free. — William Mair, Twin Cities, "William Mair: Five myths about aging," 24 Sep. 2019 The rumored benefits include boosting the skin's natural defenses against free radicals and UV radiation, as well as warding off visible signs of stress and pollution. — Allure, "Melatonin Is Trending in Skin Care Lately, But Can It Really Benefit Your Skin?," 20 Mar. 2019 This is essentially an imbalance between the production of cell-damaging free radicals and the body's ability to counter their harmful effects. — Cynthia Sass, Mph, Health.com, "7 Chia Seed Benefits, According to a Nutritionist," 27 Aug. 2019 If that wasn’t impressive enough, the ingredient can also neutralize free radical damage, helping to prevent skin cancer as well as fine lines and wrinkles in the process. — Tiffany Dodson, SELF, "8 Niacinamide Products Dermatologists Absolutely Swear By," 24 June 2019 The enzyme, like other antioxidants, can even neutralize free radicals (which have been linked to aging). — Braelyn Wood, Health.com, "Shop Kristen Bell’s Fave Skyn Iceland Eye Gels for Just $13 at Dermstore’s Anniversary Sale Right Now," 19 Aug. 2019

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'free radical.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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Last Updated

2 Dec 2019

Cite this Entry

“Free radical.” The Merriam-Webster.com Dictionary, Merriam-Webster Inc., https://www.merriam-webster.com/dictionary/free%20radical. Accessed 13 December 2019.

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