History of Supplemental Antioxidants
Continued from Part One Irradiated Food and Free Radicals:
Let’s take a quick look at the history of the free radical / antioxidant connection, and how we got to where we are today.
Denham Harman proposed The Free Radical Theory of Aging in the 1950s. The “theory” is that oxygen radicals are central in the aging process because of what is termed now as “oxidative stress” which results in damage to macromolecules and cells. Since lipids, proteins, and DNA show more oxidative damage as we age, and experiments with fruit flies genetically modified to over express antioxidants showed they had longer life cycles, the “theory” gained wide spread acceptance (However, today, experiments indicate just the opposite). http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3088106/
The problem with this is that correlation does NOT equal causation. Oxidative stress is a result of aging, not the other way around. In the body, superoxide anion is converted to hydrogen peroxide which does not readily oxidize molecules, proteins, lipids, or DNA. The amount of peroxide in cells is harmless. Iin fact, it is produced in vivo by enzymes, and is part of the body's way of reaching homeostasis, or balance.
The current evidence does not support the idea that Reactive Oxygen Species (ROS) cause a chain reaction of deleterious free radical buildup. Even if peroxides were harmful at this level the enzyme catalase would convert it to molecular oxygen and water! In other words, peroxides are a secondary source of oxygen. Air-breathers that do not have catalase do not suffer from accumulations of hydrogen peroxide. Japanese persons with acatalasemia (they do not produce catalase), in the 1950’s, were found to have nothing other than periodontal disease!
Until recently there was no way to directly test for a link between oxidative stress and aging. By genetically modifying mice at the University of Texas Health Science Center in San Antonio, Texas, researchers were able to determine there was no relationship between free radicals and aging.
Over expression of the genetic markers SOD1 and SOD2 (which are responsible for catalase production) resulted in greater resistance to oxidative stress, but did not result in longer living mice. Mice that were made to produce more of the antioxidant enzyme glutathione peroxidase 4 also did not have longer life cycles. Even when researchers had multiple over-expressed antioxidative genes, the mice lived no longer than normal.
After the results of this and other research were published, the U.S. Department of Agriculture tell us they removed the Oxygen Radical Absorbance Capacity (ORAC) database from their website:
"due to mounting evidence that the values indicating antioxidant capacity have no relevance to the effects of specific bioactive compounds, including polyphenols, on human health."
The European Food Safety Authority also issued a warning:
”A cause and effect relationship has not been established between the consumption of the food(s)/food constituent(s) evaluated in this opinion and a beneficial physiological effect related to antioxidant activity, antioxidant content, or antioxidant properties.”
After 60 years of research into antioxidants (and billions spent), not a single antioxidant compound has been found that can extend human life). Actually, just the opposite. Antioxidants such as beta carotene, Vitamin A, and Vitamin E have been shown to increase mortality.
Why do consumers and researchers buy into the myth?
The Health Halo Effect
“The food industry uses the antioxidant rap, along with the "low trans fat" come-on (and several other well-known gimmicks), to guilt-trip gullible consumers into preferring, paying more for, and consuming more of the very foods and beverages that many of us are trying to cut back on. This is the well-studied health halo effect, whereby extraordinary nutritional claims have the effect of tricking people into making irrational food decisions. (For more, see http://journalofconsumerpsychology.org/pdf/short%20articles/JCPS_10-00088_180.pdf in The Journal of Consumer Research and http://www.jstor.org/stable/10.1086/519499 in The Journal of Consumer Psychology showing that dieters are more likely than non-dieters to be tricked.) Food labels that promise "Rich source of antioxidants" are crass marketing ploys. They have nothing to do with health.”
“But there's probably a deeper reason for our collective refusal to swallow the bitter pill of scientific evidence. The actual, proven things that can reduce our risks of cancer, heart disease, diabetes – and all the other chronic nasties that come with an ageing population – are somewhat more prosaic. Don't smoke. Stay in shape. Eat a balanced diet. Limit alcohol intake. Keep active. This is hard work.”
The Decline Effect
“The science behind the association between oxidative damage and ageing is a classic example of the Decline Effect. The initial studies showing an association between decreased life expectancy in worms and damage from oxygen free radicals have not been adequately replicated. Later studies showed no such association and more recent studies showed the opposite effect: longer life span and evidence of free radicals triggering cellular repair. In other words, the initial findings “declined” over time.”
“So how come literally thousands of papers confirmed the theory? We can again find the answer in the way our brain is programmed. We tend to highlight and accept data that confirm our preconceived ideas and prejudices; and we reject and ignore evidence that does not.
“This phenomenon is well known in psychology, sociology, political science, and behavioral economics. It’s called confirmation bias. This is not to say that the scientists were incompetent or dishonest in any way—it is just the way our collective brain works. It takes extraordinary expenditure of mental energy to combat it—something our lazy brains are programmed not to do.
“This is why it took over 50 years for evidence to shake the foundations of the antioxidant theory and over 10 years to debunk the resveratrol “evidence” of prolongation of survival.”
Current Research and Evidence related to Free Radicals and Anti-oxidants
Written up in Scientific American, February 2013, and other science publications such as Nature, a study began in 2006 by David Gem, Assistant Director of the Institute of Healthy Aging at University College London, turned the free radical/antioxidant world upside-down. The lowly roundworm, aenorhabiditis elegans, had often been used in aging studies, but when Gems genetically altered the worms to not produce antioxidative enzymes he got a surprise. Instead of dying prematurely, as expected, they lived as long as a normal worm would. AND this experiment is not the exception these days.
At the Barshop Institute for Longevity and Aging Studies at the University of Texas Health Science Center in San Antonio, Arlen Richardson genetically engineered over a dozen strains of mice. Some of them produced less antioxidant enzymes and some of them more than normal. The ones with more antioxidants should have lived longer. They didn’t. Experiment after experiment with these engineered mice showed no connection between how long the mice lived and the number of free radicals in their bodies.
A biologist at McGill University, Siegfried Hekimi, bred roundworms to overproduce superoxide in order to “help us prove the theory that oxidative stress causes aging.” Instead off dying young, they did not have high levels of free radicals or oxidative damage, and they lived 32 percent longer. When he gave these worms Vitamin C the increase in lifespan was lost. He believes the free radicals cause the expression of genes that work to repair cellular damage.
In another experiment, Siegfried exposed unmodified worms to an herbicide known to cause free radical production in plants and animals. Although they were exposed from birth, in his 2010 paper he states that the worms lived 8 percent longer than worms that were not treated with the poison.
In 2012, Hekimi and his collegues deactivated all 5 genes that code for superoxide dismutase enzymes, with no reduction in the worms’ life spans.
The longest living rat, the Naked Mole Rat, has been studied for over 11 years by Rochelle Buffenstein. Though they live 8 times longer than other rats, have more free radicals at an earlier age, less antioxidants and more oxidative stress, they live without disease until they die at about 30 years old.
Not only do experiments of increased free radicals in mice and worms not show a decrease in life span, they show just the opposite; they live longer!
People aren’t off the hook either. Studies show that persons who take certain supplements are more likely to get lung cancer and heart disease. A study in 1996 found 17 percent more deaths and 28 percent more lung cancers in the group that took the antioxidants retinol and beta-carotene.
“In 2007 the Journal of the American Medical Association published a systematic review of 68 clinical trials, which concluded that antioxidant supplements do not reduce risk of death.
“In 2010 researchers at the University of California, San Francisco, and Pohang University of Science and Technology in South Korea reported in Current Biology that some free radicals turn on a gene called HIF-1 that is itself responsible for activating a number of genes involved in cellular repair, including one that helps to repair mutated DNA."
The randomized, double-blind, placebo-controlled 2008 study published in JAMA showed that neither vitamin E or C supplementation reduced heart disease. A review in the Annals of Internal Medicine concludes:
“limited evidence supports any benefit from vitamin and mineral supplementation for the prevention of cancer or CVD. Two trials found a small, borderline-significant benefit from multivitamin supplements on cancer in men only and no effect on CVD”.
There are studies that show that supplementing with vitamin A can cause liver damage, coma, and death; vitamin E supplements increased the risk of prostate cancer; vitamin C supplements accelerated atherosclerosis in diabetic women and male runners lost muscle strength (after only 1 week!); high doses of the antioxidants N-acetyl may promote the spread of breast cancer cells.
So we see that over the last decade or so a lot of experiments that were set up to support the free-radical/antioxidant/aging connection have instead challenged that very assumption. Instead what these experiments have shown is that free radicals (at certain amounts and in certain situations) are not only NOT dangerous but helpful by initiating a response in our body’s natural defense systems.
Continued in Part Three: Free the Radicals:
As I stated in Part One, leave the politics out. I have intentionally avoided discussing such things as the political lobbying power of the "37 Billion Dollar" U.S. supplement Industry*, and the deceptive marketing practices of food and supplement manufacturers (just look at Kellogg's and other lawsuits). This is not for the lack of available information. You can do your own research if you doubt politics and deception are involved.
* On the web at: nutraingredients-usa.com/Markets/NBJ-The-US-supplement-industry-is-37-billion-not-12-billion