By Vince Giuliano
Mainline scientific theories may have long lifespans but are inevitably overturned as accumulating evidence renders them obsolete and brings alternative theories to the fore. We saw this in physics over 100 years ago when relativity theory and quantum physics supplanted classical mechanics on the very small and very large scales. We saw this in biology starting some 150 years ago when many diseases became explainable not in the established terms of “spontaneous generation” but instead in terms of germs and then viruses. When such a major change in paradigm happens there is usually a period of significant and often bitter controversy between scientists seeking to hold on to the theories of the older paradigm and those espousing the newer one. This is followed gradually by changes in basic thinking patterns and a subsequent long period of fertile discovery.
Victor’s recent blog entry End of the free radical theory of aging and negative consequences of indiscriminante antioxidant supplementation points to a basic change in paradigm related to what was long-held to be a fundamental theory of aging, the free radical theory of aging proposed by D. Harman 45 years ago.
As Victor pointed out, a few earlier posts in this blog have telegraphed that all is not well with the free radical theory of aging. These posts include The free radical theory of aging. Is it really a theory of aging?, The anti-antioxidant side of the story and Another possible negative for antioxidants.
When I drafted my treatise ANTI-AGING FIREWALLS – THE SCIENCE AND TECHNOLOGY OF LONGEVITY in 2007, I set out to list the major theories of aging, and the first one listed was Oxidative Damage. I did that because at the time it was regarded to be the most classical and most widely-accepted theory of aging, holding that aging is the result of accumulative damage to tissues due to oxidative damage created by free radicals. I now will be revising the discussion in the treatise to be consistent with Victor’s blog entry and acknowledging the great deal we don’t know regarding antioxidant supplementation.
In the old oxidative damage framework, free radicals were seen as evil entities that created damage and accelerated aging. And people sought to stamp them out and live longer by taking antioxidant supplements Now we are in the midst of broadening our perspective to include acknowledging the positive roles free radicals play in crucial physiological processes, including signal transduction, cell-cycle regulation, and immune function. Indiscriminant taking of antioxidant supplements could interfere with critical processes and could be health damaging, even dangerous. This is a key message in Victor’s blog entry. And it is coming just at a time when the public is becoming familiar with the rudiments of the free radical theory and breakfast cereals, skin creams and a variety of other consumer products are being advertised as containing antioxidants. Everybody seems to know that antioxidants are good for you without question and contribute to longevity. Everybody, that is, except those who are really in the know and have their doubts.
So, we need to rethink deeply the whole issue of antioxidant supplementation. What seemed simple becomes very complex. For one matter, whether a substance is an anti-oxidant or not may not may be of secondary or of no importance to the key biological activities of that substance. There are hundreds of antioxidant substances just like there are hundreds of brownish supplement substances. But being brownish or an antioxidant may not be critically important or even relevant when considering the biological activities of that substance. A great many supplements in my suggested anti-aging firewall are anti-oxidants, but they are on the list for other reasons. Blueberries, for example are commonly touted as good for you because they are excellent anti-oxidants. Actually, they consist of complex phyto substances that act through a multiplicity of channels, and do produce a myriad of documented positive health impacts(ref)(ref). Olive oil, walnuts, dark chocolate, hot peppers, ginger, curcumin, resveratrol, green tea, caffeic acid, rosmarinic acid, grape seed extract, bitter melon, garlic, boswellia serrata are similarly plant-based phyto-substances with documented positive health impacts that happen also to be anti-oxidants. And there are several additional supplement substances that are much more than antioxidants as well, like l-carnosine, PQQ and lycopene.. Each acts through its own biological channels and saying that they are the same because they are antioxidants is like saying that they are the same because they are brownish powders in capsules.
It is no longer a sweeping game where antioxidant = good and radicals = bad. And I am not convinced that exogenous antioxidant supplementation is always bad. It is a much more complex situation in which antioxidant activity of a substance may be secondary or tertiary in its importance compared to other properties such as pathway activation, inhibition of NF-kappaB, epigenomic impact on methylation or histone acetylation, etc. In some cases such as major exposure to radiation, taking a strong mix of antioxidant supplements is probably well justified(ref).
Dozens of substances in my suggested anti-aging firewall regimen are incidentally antioxidants but most are not in the regimen for that reason. My intent was to only include substances with research-demonstrated health impacts. I don’t care if blueberries, green tea, curcumin, resveratrol, etc. are antioxidants given ample research that the net effects of these substances are health-positive.
It looks now like I have to look at some of my firewall substances and combinations of such substances from much more sophisticated viewpoints than I (or others for that matter) have used previously. I will be striving to adjust my suggested regimen accordingly. At present I see a need to start out by looking again at classical vitamins like vitamin C, alpha-tocopherol, and beta-carotene, asking what is really known about these substances individually in terms of current research above and beyond that they are antioxidants. This is a process that must be started now but is likely to take time measured in years before final answers become available.
My commitment in this blog continues to be reporting on and interpreting the sciences relating to aging, not to any favorite theories or even to what I may have written previously. I will be striving to update what I have written, however, and bring my treatise up to date with the paradigm shift connected with antioxidants.
Vince