Does Calorie Restriction Extend Lifespan in Mammals?

Until about two years ago, the story went something like this: calorie restriction extends lifespan in yeast, worms, flies, and rodents.  Lifespan extension by calorie restriction appears to be biologically universal, therefore it's probably only a matter of time until it's demonstrated in humans as well.  More than 20 years ago, independent teams of researchers set out to demonstrate the phenomenon in macaque monkeys, a primate model closer to humans than any lifespan model previously tested.

Recent findings have caused me to seriously question this narrative.  One of the first challenges was the finding that genetically wild mice (as opposed to inbred laboratory strains) do not live longer when their calorie intake is restricted, despite showing hormonal changes associated with longevity in other strains, although the restricted animals do develop less cancer (1).  One of the biggest blows came in 2009, when researchers published the results of a study that analyzed the effect of calorie restriction on lifespan in 41 different strains of mice, both male and female (2).  They found that calorie restriction extends lifespan in a subset of strains, but actually shortens lifespan in an even larger subset.  Below is a graph of the effect of calorie restriction on lifespan in the 41 strains.  Positive numbers indicate that calorie restriction extended life, while negative numbers indicate that it shortened life:

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SOCIAL MEDIA AND THE MEDICAL PROFESSION

I am a Luddite when it comes to social media, the web-based interactive media such as Facebook and other more professionally oriented ones like Linkedin.  I do have a Facebook page but I rarely use it. I have a blog where I post my poetry http://stephenleeder.blogspot.com.au/but no one ever visits and another blog where I post extended versions of articles like this
http://steve-leeder-better-health.blogspot.com/. And yes, I have Tweeted 30 times!  Basically, I stick to email.

But my youngest son (19) belongs to a generation for whom social media are a principal social communication channel. Recent medical graduates know all about it and how to use it wisely and well. It serves to link doctor to doctor and to some extent patient to doctor.

Social media according toWikipedia includes “web- and mobile-based technologies that are used to turn communication into interactive dialogue among organisations, communities and individuals”.

Today, news travels like lightning via Twitter and Facebook.  "A common thread," says Wikipedia, "running through all definitions of social media is a blending of technology and social interaction for the [rapid] co-creation of value."

Social media are cheap to use.  Anyone can publish on them unlike on the commercial media.  And they are immediate: whereas it may take weeks to get an idea into print, with social media communication is now. You can edit an article easily on social media whereas reprinting to correct an error is a nightmare. 

Are the social media likely to be professionally useful?  My guess is that they will prove to be so.  A group of general practitioners could use social media to discuss how best to manage a group of patients in a local nursing home. But they might get their fingers burnt unless the social medium they were using was fenced off, like a gated village, for their use alone. 

Australian Doctorhas established docs4docs for that purpose.  Take a look at http://just4docs.com.au/index.php/forums/topic/26/medicare-localsand see as an example a series of depressing conversational comments on Medicare Locals

If you are going to use social media for professional purposes please be careful.  A list of questions to ask yourself before you get too deeply into social media were provided in a paper published in the Medical Journal of Australia last year by a working group drawn from the AMA Council of Doctors in Training, NZMA Doctors-in-Training Council, AMSA, and the New Zealand Medical Students’ Association (NZMSA).

A guide from which the MJA paper was drawn can be found at http://ama.com.au/socialmedia.  Here are the questions.

Have you ever Googled yourself? Do you feel comfortable with the results that are shown?

Have you ever:

• Posted information about a patient or person from your workplace on Facebook?

• Added patients as friends on Facebook or MySpace?

• Added people from your workplace as friends?

• Made a public comment online that could be considered offensive?

• Become a member or fan of any group that might be considered racist, sexist, or otherwise derogatory?

• Put up photos or videos of yourself online that you wouldn’t want your patients, employers or people from your workplace to see?

• Felt that friends have posted information online that may result in negative consequences for them? Did you let them know?

• Checked your privacy settings?

So there you have it!  Good luck but take care!

Madonna's "MDNA Show Manifesto" Defends Using Guns on Tour: Do You Agree?

As we speak, Madonna is en route to my city- Philadelphia, to launch the North American leg of her "MDNA World Tour".  In advance of her arrival, she has released a statement to the local Metro defending one of the most controversial parts of her tour...the use of fake firearms in concert.  Here is a portion of that statement:

"It's true there is a lot of violence in the beginning of the show and sometimes the use of fake guns - but they are used as metaphors.  I do not condone violence or the use of guns.  Rather they are symbols of wanting to appear strong and wanting to find a way to stop feelings  that I find hurtful or damaging.   In my case its wanting to stop the lies and hypocrisy of the church,  the intolerance of many narrow minded cultures and societies I have experienced throughout my life and in some cases  the pain I have felt from having my heart broken".

Gun violence is (unfortunately) not a new problem.  However, the topic is quite timely due to increased U.S. media coverage following several mass shootings in the past few weeks- Aurora, CO, Oak Creek, WI, and New York, NY.  The issue of gun violence has reached crisis levels in Philadelphia where Madonna will be performing.  A new open source journalism project called http://guncrisis.org/ "contends that there is an epidemic of homicide by gunfire in Philadelphia and similar cities".  They are seeking solutions.

The solutions being sought by GunCrisis: Philadelphia and others involve taking a public health approach to gun violence.  The recent high profile shootings have produced several well-written pieces about gun violence and what we need to do next:

•  Prompt policy discussions about easy access to ammunition, high-capacity magazines, and assault weapons.
• Use our public health skills to conduct further research into the causes of firearm injuries.
• Examine gun violence as a social disease- one that stems from a society "saturated with guns".

Tell me what you think:

Do you believe that the gun "saturation" goes beyond those in our homes to include those used for entertainment?  E.g., Guns in movies or video games; Madonna's concert props

Is Madonna successful? Does using guns as a metaphorical image help her reach her goals and battle against hypocrisy and intolerance?

In addition to those listed above, what other strategies should we incorporate into a public health approach against gun violence?

AHS11 Talk Posted

After a one-year delay, my talk from the 2011 Ancestral Health Symposium is online with slides synched.  The talk is titled "Obesity: Old Solutions for a New Problem", and it's an overview of some of the research linking food reward to food intake and body fatness.  This is the talk that introduced a fundamentally new idea to the ancestral community: not only does the chemical composition of food matter, but also its sensory qualities-- in fact, the sensory qualities of food are among the primary determinants of food intake.  I didn't come up with the idea of course, I simply translated the research for a more general audience and put my own evolutionary spin on it.

The talk would be a bit different if I were to give it today, as my understanding of the subject has expanded, and my speaking skills have improved.  However, the central message remains as true today as it was a year ago.  You can find the talk here.

The slide synching was done by an extremely generous man named Ben Fury.  As you can see in the video, he did an excellent job.  Without Ben, this video would have remained in internet limbo forever.

Below, I've published a message from Ben explaining the interesting work that he does.  Please contact him if you think it's interesting.

A Message from Ben Fury

I was writing a book on health, fitness and diet in 2009 when my house burned down in the Station Fire, along with 165,000 acres of my beloved Angeles National Forest. Since then, I've had a series of people needing help come through my life, that have upgraded and morphed my talents...

Seniors with chronic pain, falls, brittle bones, and stiff shrunken muscles.
Diabetics with out of control blood sugars, going blind, and having limbs lopped off.
Neurologically challenged people with spastic limbs and foggy brains.
Fat, listless, unhappy people with no idea how they got that way, seeing no way out of the darkness.
Each of them needing help in different ways, but all with an underlying theme of what works to help heal our conditions:

•     Remove flour, sugar, beans, and heavily processed oils from our diet. Eat real food.
•     Get strong.
•     Get flexible.
•     Stop ceding health responsibility to outside forces, and take charge of our own wellness.
•     Only use truly evidence based medicine. Don't just pop the latest pill or get the latest surgery all the other people are doing. Be wary of the disease mongers in both the conventional and alternative camps.
•     Find our "happy thoughts." Use the simple restoratives of sleep, play, and reflection, to let go of pain, find inner peace, and let in joy and purposeful outer direction.

The methods to accomplish these goals are varied, and I have both non-profit and for-profit ventures to share them.
Their websites are currently in development.
The for-profit is BenFury.com
The non-profit is PainRelieversUSA.org , whose mission statement is:

To move beyond pain management...
and learn to live pain free.

Feel free to write to me  at: ben [at] benfury dot com

Ancestral Health Symposium 2012

I recently returned from AHS12 and a little side trip to visit family.  The conference was hosted at Harvard University through the Harvard Food Law Society.  Many thanks to all the organizers who made it happen.  By and large, it went smoothly.

The science as expected ranged from outstanding to mediocre, but I was really encouraged by the presence and enthusiastic participation of a number of quality researchers and clinicians. The basic concept of ancestral health is something almost anyone can get behind: many of our modern health problems are due to a mismatch between the modern environment and what our bodies "expect".  The basic idea is really just common sense, but of course the devil is in the details when you start trying to figure out what exactly our bodies expect, and how best to give it to them.  I think our perspective as a community is moving in the right direction.

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Lorcaserin: the Latest FDA-approved Obesity Drug

The FDA recently approved a new drug called lorcaserin (brand name Belviq) for the treatment of obesity.  Lorcaserin causes an average of 13 lbs (5.8 kg) of weight loss over a year, compared to 5 lbs (2.2 kg) for placebo (1), which is less than the other recently approved drug Qsymia (formerly Qnexa; topiramate/phentermine).

Learning about obesity drugs is always a good opportunity to gain insight into the mechanisms that underlie the development and reversal of obesity.  If you've been following this blog for a while, you already have a pretty good guess what organ this new drug acts on.  Make your guess and read on!

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Two Great Quotes About Obesity (technical)

By Dr. Hans-Rudolf Berthoud, from a recent paper, "The Neurobiology of Food Intake in an Obesogenic Environment" (1).  I came across it because it cites my review paper (2).  My perspective on obesity is similar to his.  From the abstract:

The modern lifestyle with its drastic changes in the way we eat and move puts pressure on the homoeostatic system responsible for the regulation of body weight, which has led to an increase in overweight and obesity. The power of food cues targeting susceptible emotions and cognitive brain functions, particularly of children and adolescents, is increasingly exploited by modern neuromarketing tools. Increased intake of energy-dense foods high in fat and sugar is not only adding more energy, but may also corrupt neural functions of brain systems involved in nutrient sensing as well as in hedonic, motivational and cognitive processing.

And a nice one from the conclusions:
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