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What Are Free Radicals? Free radicals are reactive elements that want to steal electrons from compounds that they come into contact with. Simply put, they are molecules having more electronic value with a negative oxygen atom , such as: O2, H2O2, OH. Free radicals in our body are organic molecules responsible for aging, tissue damage, and possibly some diseases. These molecules are very unstable, therefore they look to bond with other molecules, destroying their vigor and perpetuating the detrimental process.
Because of these characteristics free radicals play an important role in
health care. Throughout life our body often encounters harmful bacteria
and viruses. Free radicals would be produced to destroy enemies in our body. In other words, under normal circumstances,
free radicals are the best army in our body. However, the annoying side
of radicals is not only they kill enemies, but sometimes also attack and
damage cells of our body.
How is Free Radical Formed?
Free radicals are produced in most cells of the body as a byproduct of metabolism,
although some cell types manufacture larger quantities for specific purposes.
The most important free radicals found in aerobic cells, such as those
in humans, are oxygen, super oxide, hydroxyl radical, hydrogen peroxide,
and the transition metals. When free radicals are formed within cells, they can
oxidize molecules used inside cells (especially lipids) and
thus cause cell death and injury. However, the human body has developed
various mechanisms in order to protect itself from the damaging effects
of free radicals. There are enzymes which decompose peroxides and transition
metals; other free radicals are sequestered by proteins and other molecules.
How do they affect human health?
Free radicals are usually present for very
short periods only and react with other molecules very quickly. In
recent years, it has become accepted that they play an important part in
several medical conditions. DNA is particularly susceptible to oxidation
by free radicals and it has been suggested that these substances may play
a role in the mutations which precede the development of cancer.
This may explain why some transition metals, such as nickel and chromium,
are carcinogenic under certain circumstances. Free radicals have also been
implicated in atherosclerosis, liver damage, lung disease, kidney damage,
diabetes mellitus, and ageing. It is not always easy to tell if free radicals
are the cause of a disorder or a result of some other causative agent.
Of particular importance is that free radical damage accumulates with age.
How to avoid free radical damage? Antioxidants, present in many foods, are molecules that prevent free radicals from harming healthy tissues. There are numerous ways to avoid or minimize free radical damage. The following are some of the measures we can take:
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