Does Calorie Restriction Extend Your Life Span?

no calorie

While researching a previous blog investigating if it is possible to live forever, I came across an article discussing various “proven methods” that expand one’s life span.  One method that caught my eye in particular is called calorie restriction.  Calorie Restriction is simply limiting one’s daily caloric intake to about 80% the recommended amount while still consuming all of the necessary nutrients.  This is supposed to slow the aging process altogether, and prevent various age related diseases.  My first instinct when I read this is that it must be too good to be true.  However, if  this is true, why don’t we all do this?  So, I figured I would investigate.

As I began investigating this topic, it became apparent that the scientific process taking place to answer the question of calorie restriction reflects what we have learned in class.  The first step is to preform a randomized controlled trial on mice.  In this trial, mice were randomly allocated to six different groups.  Each group was fed food according to different regimented diets.  These diets varied in the amount of calories consumed and what those calories were.  After the trial, it was discovered that the group of mice whose diet was restricted to 65% the normal amount of calories (the amount of calories given to the control group) lived the longest which equates to a 20-40% increase in lifespan.  These findings were published in the national library of medicine and are accepted around the scientific community.  Even though it was proven that calorie restriction increases the lifespan of mice, this in no way proves the impact of calorie restriction on humans.  The next logical step to take after this trial is to conduct a calorie restriction test on animals that share more similarities to humans than mice.  This is precisely what Richard Weindruch of the University of Wisconsin did.

In April of 2014, University of Wisconsin scientist Richar Weindruch released his results from a 25 year long experiment which began in 1989.  The experiment compared 76 Rhesus monkeys who were put on a diet restricted to 70% the normal caloric intake to monkeys that ate as they wished.  Weindruch and his team discovered that Monkeys allowed to eat what they wanted were almost 3 times as likely to contract diseases and their chance of mortality increases 3 times that of the experimental group.  These findings are influential because they display that calorie restriction increases the life span of primates.  However, there has yet to be a mechanism discovered that would correlate calorie restriction to increased life span.  The lack of a mechanism does not discredit this experiment, it simply means there is more to be researched.

Considering these two findings, the next step in proving  that calorie restriction works in humans would be a randomized control trial of humans.  However, a trial like this is nearly impossible to conceive.  This is because it would take upwards of 100 years to complete and is controversial because it could potentially put people’s lives in danger.  If calorie restriction has adverse effects on humans, an experiment like this could cause premature deaths of the subjects.  
Thus, even though there is ample evidence to suggest that calorie restriction may increase a person’s life span, we are far from a definite answer.  Evidence of this fact is in the Times article that states there is absolutely no convincing evidence that calorie restriction works in primates.  Like any science, there are people on both sides of the issue arguing for their point of view.  The only way to answer this question for sure it through a randomized control trial of humans, but a trial like this will most likely never take place due to ethical issues.  There is great commercial intrigue around this topic because if a mechanism could be discovered, companies might be able to make some sort of pill that actually slows down the aging processes.  The possibility of a supplement like this is extremely exciting and will most likely drive more research on this topic for years to come.

Work Cited:

http://healthland.time.com/2012/08/29/want-to-live-longer-dont-try-caloric-restriction/

http://news.wisc.edu/22672

http://www.ncbi.nlm.nih.gov/pubmed/3958810

https://www.fightaging.org/archives/2002/11/calorie-restriction-explained.php

 

 

2 thoughts on “Does Calorie Restriction Extend Your Life Span?

  1. Eric Choi

    Whenever I think of calories, I think of how the bodybuilders who work out eat a LOT of calories so they can maintain their gains. I have been eating a ton of calories because I have recently decided to bulk up. Another idea you could probably use for a future blog post is the life expectancy of a bodybuilder. Do they have a shorter lifespan because they consume all those calories? I agree with how ethics would come into play if scientists tried to do an actual randomized control experiment with humans. Why would we manipulate variables which could possibly cause humans to die quicker? Anyways, here is an article I found which explains the effects of weight lifting and overconsumption.
    http://www.diseaseproof.com/archives/diet-myths-bodybuilding-diet-bad-idea.html

  2. Erin Ann Alessandroni

    Adam, this post was extremely well written! You did a fantastic job incorporating topics and definitions we speak about in class with your research. The title of this post grabbed my attention due to the fact that according to my prior knowledge, restricting calories by percentages as large as those above could potentially constitute life threatening eating disorders such as anorexia, thus contradicting the hypothesis mentioned above. I would presume that there is a “happy medium” between eating above the suggested caloric intake (leading to morbid obesity) and restricting the caloric intake as researched (seemingly presenting a danger, rather then a positive impact, to the human lifespan). I assume that there is a reason correlated with an immense amount of research conducted by countless researchers that led to proposing the suggested number of calories human beings should take in per day. One would think that this number is clearly the best for elongating human life. The fact that one study done with monkeys proves everything I have addressed incorrect is extremely interesting. The Times article you researched talks about a more recent study done with monkeys that contradicts the one conducted by Richar Weindruch. Times explains that this evidence, in addition to observational evidence of humans restricting their diets, shows that our species should most definitely not restrict calories in an effort to live longer.

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