Final answer:
Antioxidants, including vitamins A, C, E, beta-carotene, and selenium, protect the body from the damaging effects of free radicals. They can act locally or globally to neutralize free radicals and prevent oxidative damage, contributing to cellular health and longevity.
Step-by-step explanation:
The category of nutrients that protect the body from free radicals and the cellular damage they cause are antioxidants. Antioxidants such as Vitamin A, Vitamin C, Vitamin E, beta-carotene, and selenium prevent damage from free radicals which are highly reactive molecules with unpaired electrons. These molecules can be formed through natural metabolic processes or through environmental factors such as radiation and pollution.
Antioxidants provide a defense mechanism by being oxidized themselves, thus halting the destructive chain reactions initiated by free radicals. They can act globally or locally within specific regions of the body, such as vitamin E in the colon. Moreover, beta-carotene is considered a provitamin because it can be converted into Vitamin A in the body, further contributing to the antioxidant defense system.
Some antioxidants work by scavenging the harmful by-products of metabolism – the free radicals – transforming them into less reactive molecules that can be more easily excreted. This process is essential for maintaining cellular health and preventing oxidative damage that can contribute to aging and various diseases.