 |
| Left Starved Monkey, Right Normal Diet Monkey National Institute on Aging / NIH |
A recent study on the effects of "starvation" diet and longevity of life in rhesus monkeys was published last August in Nature. The title given in a NY Times article was "Severe Diet Doesn’t Prolong Life, at Least in Monkeys." I am just a chiropractor so I am by no means an expert. I feel that a good research article needs a dose of common sense. It is easy to get lost and sometimes the numbers can be deceptive without common sense judgements. I bring this article up because I feel that this is the case just like claims that the only benefits to kinesiotape were placebo. I just find this research experiment fascinating also. It all started in July 10, 2009 in an article in Science, "Caloric Restriction Delays Disease Onset and Mortality in Rhesus Monkeys" which sounded like the secret to longevity in humans. Around that time, it was also shown to be the same with mice also. The obvious benefits to a caloric restricted diet were reduced heart disease, cancer and diabetes but the increased lifespan was a surprising claim. Another study in 2009, found that mice did not have benefits to reduced diets. There is an importance to repeatability with the scientific theory. Primates are closer to humans so this got little attention. It is now 2012 and there is another primate study on caloric restriction over 25 years with contradictory conclusions to the 2009 primate study. Dr. Rafael de Cabo saw no difference in lifespan when including disease-related deaths like cancer, heart attacks, etc. while the University of Wisconsin 2009 study eliminated non-age related deaths. There are differences with the two groups of monkeys also. Besides the caloric restricted diet group, the control group was fed a diet that was thought to be healthy for normal monkeys. In 2009, the control monkey group was fed unlimited food. Therefore, you cannot say these studies are alike as they are like apples to oranges. If there is any increase in lifespan, the effect might be more subtle with monkeys with healthy diets. Perhaps, the study size might not be enough to see a minor difference. Then you would need more studies and more data points to plot curves of when does caloric restriction affect lifespan. The 2012 study would be one data point in the diet vs lifespan curve similar to when they study different dosages of medication with disease efficacy. The components of the diets may also matter. One does not expect a pure caloric restricted diet full of junk food to live longer. I find it ironic that the author of the 2012 study is overweight also as people's biases can affect people's perception of data. I am bringing up skepticism because when you look at the picture above, I see many differences between the two monkeys. Maybe the author coincidently chose the most healthy "starved" monkey and the most unhealthy control monkey. You can see the difference in hair color, muscle tone and posture between the two monkeys. I wish they would have studied how active and playful the monkeys are as well as the mental acquity between the two groups. I do not advocate starvation diets as I see too many risks. I see too many people fall into the viscous cycle with fad diets by slowing down their metabolism and reducing their muscle mass as the body scavenges the body's own tissues to keep you alive. When the person returns to a normal diet, the weight is gained back and there is more weight gain from the slower metabolism. I do believe, however, that what we perceive as a normal healthy diet is grossly overestimated as a society. I hope scientists continue to study this issue as I believe that we understand only a fraction of how the body works. I can definitely say this about pain and the causes of pain.
ChiroWorks Care Center
Anthony Tsai, D.C.
Chiropractor in San Jose, CA
Graston Technique Certified
FAKTR Certified
Disclaimer: The content in this blog is for informational purposes only and an opinion for specific individualized circumstances. It is not a prescription for therapy or diagnosis for you. All opinions expressed and any referenced articles are solely those of the particular author and do not necessarily represent the opinions of Anthony Tsai, Graston Technique®, its employees, providers or affiliates. Any opinions of the author on the site are or have been rendered based on scientific facts and/or anecdotal evidence, under certain conditions, and subject to certain assumptions, and may not and should not be used or relied upon for any other purpose, including but not limited to for use in or in connection with any legal proceeding. If there is any issue with the content or images on this blog, contact us an we will remove it immediately. Please refer to http://fairuse.stanford.edu/Copyright_and_Fair_Use_Overview/ for more information.
References:
http://www.nature.com/nature/journal/vaop/ncurrent/full/nature11432.html
http://www.nytimes.com/2012/08/30/science/low-calorie-diet-doesnt-prolong-life-study-of-monkeys-finds.html?pagewanted=all
http://www.sciencemag.org/content/325/5937/201.short
Comments