Antioxidants are widely used in dietary supplements and have been investigated for the prevention of diseases such as cancer. Although initial studies suggested antioxidant supplements might promote health. Later large clinical trials with a limited number of antioxidants detected no benefit, and even suggested excessive supplements with certain brand antioxidants maybe harmful.
A paradox in metabolism also exist, stating that the vast majority of complex life on earth requires oxygen for its existence. Oxygen is a highly reactive molecule that damages living organisms producing reactive O2 species. Consequently multi cell organisms contain a complex network of antioxidant metabolites and enzymes work together to prevent oxidative damage, to cellular components such as DNA, protein and lipids.
The reactive oxygen species in cells include hydrogen peroxide (H2O2), hypochlorous acid (HCIO) and free radicals such as Hydroxyl radical (OH) and Superoxide anion (O2). Therefore, the hydroxyl radical is particularly unstable, and will react rapidly, and non specifically with most biological molecules. This species is produced from hydrogen peroxide in a process called metal catalyzed redox reaction ( Fenton’s Reagent.)
These oxidants can damage cells by starting chemical reactions such as lipid peroxidation, or be oxidizing DNA or proteins. damage to DNA strands can cause mutations and possibly cancer, if they’re not reversed by DNA repair mechanisms. The damage to proteins can cause enzyme inhibition, denaturation and protein degradation. In many of these cases, it’s unclear if oxidants trigger the disease, or if they are produced as a post secondary consequence of the disease.
Several antioxidant enzymes…. such as superoxide dismutase, catalase, glutathione reductase, glutathione S -transferase et cetera… protects DNA from oxidative stress. While there is some evidence to support the role of oxidative stress in aging and chronic stress. Certain aspects can influence a positive outcome into your favor while putting the brakes 0n cancer.
While a low calorie diet extends median and maximum lifespan and also telomeres and aging expectancy. A diet also high in vegetables and fruit at a five to one ratio, because of the natural sucrose in fruit. Which are high in antioxidants and important vitamins and minerals, promote health while reducing the effects on aging.
Also there is strong evidence that one of the adaptation from exercise is a strengthening of the body’s main antioxidant defenses, particularly the glutathione system that regulates any increased oxidative stress. This effect may be to some extent protective against the diseases associated with oxidative stress. This blog post provides a better understanding to the importance of better nutrition and regular exercise.
http://www.youtube.com/watch?v=lBngws_cWho