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How the world got lost on
the road to an anti-aging pill
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January 18, 2017: by Bill Sardi
With recognition human studies of aging and longevity would take many decades to produce conclusive evidence, researchers who study aging must resort to studying animals with shorter lifespans in an attempt to discover strategies for humans to live longer and healthier.
One such strategy is calorie restriction that doubles healthspan and lifespan of lower life forms and small animals. For larger-bodied longer-living animal studies, the primate monkeys, researchers had to wait more than two decades when animals began to die off to determine differences in survivability.
But after researchers held their breath and waited so long, two monkey studies published in 2009 and 2012 came to different conclusions.
The first study, published in 2009, studied animals housed at the University of Wisconsin [Science Magazine July 10, 2009] and the other study, published in 2012 [Nature Sept 2013], compared animals at the National Institutes of Aging (NIA).
The NIA study concluded calorie restriction did little to prolong survival but University of Wisconsin researchers countered by saying the NIA control monkeys weren’t eating enough food to be good comparisons with calorie restricted monkeys (they were on a low-grade calorie-restricted diet, they said).
The researchers involved in both studies met to compare their data and see if they could come to some conclusion. [Nature Communications Jan 17, 2017] What had been consistently shown in lower animals (fruit flies, roundworms) became clear: put monkeys on a westernized but calorie-restricted diet and clear survival benefits will be observed.
As an aside, it is reported that blood samples have repeatedly been taken from these animals over the decades of the study. Blood sampling is akin to blood letting which is a known anti-aging strategy via iron loss. [Archives Internal Medicine Oct 10, 2011; British Journal Hematology Jan 2014] Some of the positive effects of a calorie-restricted diet in the primate animal lab may be attributed to blood/iron loss.
Cancer was the most common cause of death among these primate monkeys. Calorie restriction is now considered a strategy to prevent and even treat cancer. [Biochimica Biophysica Acta Nov 19, 2016]
Researchers have been reluctant to advise the public to adopt limited calorie diets but fasting has long been practiced and is now even being considered to prolong life among cancer patients. Recent Results in Cancer Research 2016]
A third set of monkeys housed at the University of Maryland was the first to report a positive association of calorie restriction with survival (a 2.6-fold increased risk of death for normally-fed versus calorie-restricted animals.
In regard to maximum lifespan, six of the 20 monkeys put on a calorie-restricted diet lived past 40, and one male is now 43, making him the oldest known rhesus monkey. This is akin to a human living ~119 years.
Since 2003 when David Sinclair at Harvard Medical School first reported that resveratrol (rez-vair-ah-trol), a red wine molecule, activates a known survival gene (Sirtuin1) that is also activated by calorie restriction, the race to develop a molecular mimic of calorie restriction was on. [Nature Sept 11, 2003]
It has now become clear that “pharmacologically targeting aging appears to be more effective in preventing age-related pathology compared with treatments targeted to particular pathologies.” [Trends Pharmacological Science May 2016]
What researchers have accomplished in the interim between 2003 when resveratrol was first posed as a molecular mimic of a calorie-restricted diet and today appears to be a bunch of contrived roadblocks, such as the false argument resveratrol is not biologically available or that proper dosing has not been established.
Dr. Sinclair, who has been taking resveratrol for over a decade, says: “We now have the technology to prevent multiple diseases at once.” [Washington Post Aug 17, 2015]
David Sinclair now says: “we will one day be able to keep active through a simple pill. When I started in the field, I did not believe that I would see medicines that slow aging become a reality in my lifetime. Now I’m sure that I will. The only question is when.” [Slate.com]