Oxidative Stress: Difference between revisions

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===Antioxidant Supplements ===
===Antioxidant Supplements ===
Antioxidant supplements have gained popularity as potential aids in combating oxidative stress and its related aging processes. These supplements are concentrated forms of antioxidants that can be taken in addition to a regular diet.
Antioxidant supplements have gained popularity as potential aids in combating oxidative stress and its related aging processes. These supplements are concentrated forms of antioxidants that can be taken in addition to a regular diet. However, antioxidant supplements have not shown preventive effects and may be harmful with unwanted consequences to our health. The optimal source of antioxidants seems to come from our diet, not from antioxidant supplements.{{pmid|24241129}}
 
Older observational studies and some randomized clinical trials with high risks of systematic errors ('bias') have suggested that antioxidant supplements may improve health and prolong life. A number of randomized clinical trials with adequate methodologies observed neutral or negative results of antioxidant supplements. Recently completed large randomized clinical trials with low risks of bias and systematic reviews of randomized clinical trials taking systematic errors ('bias') and risks of random errors ('play of chance') into account have shown that antioxidant supplements do not seem to prevent cancer, cardiovascular diseases, or death. Even more, beta-carotene, vitamin A, and vitamin E may increase mortality.{{pmid|17327526}} Some recent large observational studies now support these findings. According to recent dietary guidelines, there is no evidence to support the use of antioxidant supplements in the primary prevention of chronic diseases or mortality.{{pmid|22419320}}{{pmid|24241129}}


Here's a list of some widely used antioxidant supplements:
Here's a list of some widely used antioxidant supplements:
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* '''Alpha-Lipoic Acid''': A compound that works with mitochondria and the body's natural antioxidant defenses.
* '''Alpha-Lipoic Acid''': A compound that works with mitochondria and the body's natural antioxidant defenses.
* '''Green Tea Extract''': Rich in catechins, green tea extract is renowned for its antioxidant properties.
* '''Green Tea Extract''': Rich in catechins, green tea extract is renowned for its antioxidant properties.
=== Limitations and Considerations ===
While antioxidants in general are beneficial, their supplementation is not without limitations. Antioxidant supplements have not shown preventive effects and may be harmful with unwanted consequences to our health. The optimal source of antioxidants seems to come from our diet, not from antioxidant supplements.
Older observational studies and some randomized clinical trials with high risks of systematic errors ('bias') have suggested that antioxidant supplements may improve health and prolong life. A number of randomized clinical trials with adequate methodologies observed neutral or negative results of antioxidant supplements. Recently completed large randomized clinical trials with low risks of bias and systematic reviews of randomized clinical trials taking systematic errors ('bias') and risks of random errors ('play of chance') into account have shown that antioxidant supplements do not seem to prevent cancer, cardiovascular diseases, or death. Even more, beta-carotene, vitamin A, and vitamin E may increase mortality.{{pmid|17327526}} Some recent large observational studies now support these findings. According to recent dietary guidelines, there is no evidence to support the use of antioxidant supplements in the primary prevention of chronic diseases or mortality.{{pmid|22419320}}{{pmid|24241129}}
A 2007 meta-analysis finds that in studies with a low risk of bias (randomization, blinding, follow-up), some popular antioxidant supplements (vitamin A, beta carotene, and vitamin E) may increase mortality risk (although studies more prone to bias reported the reverse).


== Conclusion ==
== Conclusion ==