Monday, July 28, 2008

What is Obesity?

Don’t worry - I am not going to take off on a discussion about whether obesity is a disease or “simply” a risk factor. I am also not going to discuss again obesity definitions - anthropometric or otherwise.

Today’s post is simply about an analogy that may help sharpen our clinical thinking around excess weight.

Think of someone who has an elevated plasma creatinine level (a marker of kidney failure) - the elevated creatine definitely tells us that there is something “wrong” with the kidneys, but that’s about it. From the creatine level alone we can certainly tell that the kidneys are failing in their excretory function, but we cannot tell what is causing the kidneys to fail - is it a pre-renal, intra-renal or post-renal problem? We can probably list a 100 reasons why kidneys could fail and obviously the treatment (apart from some very general principles) will very much depend on the cause, i.e. the actual diagnosis.

In many ways, one can look at excess body fat simply as a sign or symptom of the fact that there is a something “wrong” with energy homeostasis. The excess body fat tells us nothing about what the problem is - sure, it’s either excessive food intake or reduced energy expenditure - but that is like saying that the creatinine levels are elevated because the kidney is not excreting properly. I can think of a long list of reasons or factors that would contribute to excessive caloric intake or reduced energy expenditure: sociocultural factors, psychological factors, biomedical factors - figuring out what exactly is causing the energy imbalance is the real problem.

Only when we find what is causing the excessive intake will we have made a diagnosis of what is causing the problem - a few specific examples could include: poor meal planning, peer pressure, hedonic overeating, depression, obesogenic medications, binge eating disorder, defective satiety signaling, etc. The point is that till we know what is causing the overeating, we can’t fix it, which means we will have little success in treating the weight problem and will be limited to a “symptomatic” approach - just eat less!

Similarly, when the problem appears to be lack of activity, again the question is what exactly is causing the problem. Obviously if the problem is lack of time our approach will hopefully be very different than if the problem is back pain or lack of motivation (a possible symptom of sleep apnea, exhaustion or depression). A “symptomatic” but useless approach would be to simply recommend 10,000 steps. No better than offering an ice-pack to someone with a fever.

Just as the term “kidney failure” only tells us that there is something “wrong” with the kidneys the term “obesity” only tells us that there is something “wrong” with energy homeostasis.

In itself, neither the term “kidney failure” nor “obesity” is a real diagnosis - they are only helpful if they prompt further investigation into what might have or is still causing the problem. Only when we find the cause will we be on our way to solving the problem.

AMS
Edmonton, Alberta

VN:F [1.5.8_856]
Rating: 0.0/10 (0 votes cast)
VN:F [1.5.8_856]
Rating: 0 (from 0 votes)

Leave a Comment

In The News

Diet, exercise not enough for some patients

Apr. 10, 2012 CBC – "Dr. Arya Sharma, chair of obesity research and management at the University of Alberta, applauds Williams for airing the issue publicly, saying there is a lot of stigma attached to being fat — and even more to using surgery to address the problem." Read the article

» More news articles...

Publications

"Effect of gastric bypass surgery on azithromycin oral bioavailability."

» Browse and download more journal publications...

Watch Dr. Sharma in the News!

Dr. Sharma - CTV NEWS Videos

Listen to Dr. Sharma!

Dr. Sharma - on CBC.ca

Watch Dr. Sharma on Listen Up


  • Subscribe via Email

    Enter your email address:


    Delivered by FeedBurner

  • Arya Mitra Sharma
  • I Twitter!


  • Disclaimer

    Postings on this blog represent the personal views of Dr. Arya M. Sharma. They are not representative of or endorsed by Alberta Health Services or the Weight Wise Program.
    • Recent Posts

    • Archives

       

    • RSS Weighty Matters

    • RSS Dr Eye Candy

    • Click for related posts

    • Disclaimer

      Medical information and privacy
      Any medical discussion on this page is intended to be of a general nature only. This page is not designed to give specific medical advice. If you have a medical problem you should consult your own physician for advice specific to your own situation.


    • Meta

    • Obesity Links

      • Average blog rating:

        9.0


      • Home | News | KOL | Media | Publications | Trainees | About
        Copyright 2008 Dr. Arya Sharma, All rights reserved.
        Blog Widget by LinkWithin