Posted by: lemonator | December 16, 2008

Check Yo Methods/THATS NOT SCIENCE!

Lemonator here with another article displaying shoddy research practices.  I’ve decided to use TWO titles, depending on where the offense lies.  ‘CHECK YO METHODS’ will be articles which display shoddy research methodologies.  ‘THATS NOT SCIENCE’ will be articles which, well, have reasonable science behind it, but the journalist’s interpretations are all wrong.  Most articles will fall somewhere in between these two.   [Note:  Thank you to Erin and Tri to Cook for the name suggestsions!]

The article for today… does not entirely lead you astray, but its conclusions are, well… somewhat obvious.  I cant find the original article, so I cant be sure where the true miscommunication lies.

Vigorous Exercise blunts effects of ‘fat’ genes

Now, first, a few background notes:  The gene in question is the gene FTO, which yes, is tied to increased weight gain.  A particular variant form (has a mutation in it) works in an additive fashion.  Each copy you have (you can have up to two) increases your weight by, on average, 3 pounds.  Research is unclear as to why this is the case, but there is some indication that the gene gives you more or less of a ‘sweet tooth’ and makes you prefer certain types of foods to others.  We *do* know that it doesn’t change how you digest the food or when you feel full…

Anyways, this article makes a startling claim:  Vigorous exercise is associated with lower average weight.  I know.  Stop the presses 😀

In this article, the researchers looked at 704 Amish men and women, and found that in general the link between the variant and weight was less in the study than in normal individuals, and for those who exercised more vigorously, the correlation disappeared entirely.  They suggest that if you want to fight off the effects of this gene, you should exercise more, and it will be possible.   But… this is not exactly what they are saying.  They are saying instead:  become a vigorously exercising Amish, and *then* you will overcome your weight problems.

First, some statistics about the Amish, then… some comments about the validity of this entire study.

  • Amish men walk ~18,500 steps a day.  Amish women ~14,200.  Thats 7-10 miles a day.
  • Men report 10 hours/wk of vigorous activity, 43 hrs/wk moderate activity, 12 hrs/wk walking
  • Women report 3.4 hrs/wk vigorous, 39 hrs/wk moderate, 6 hrs/wk walking
  • 4% of the population is obese (30% in US in general)
  • The Amish eat a LOT more than we do, but a lot LESS processed food

Okay!  So… the bad news.  Only very active Amish can ‘fight’ the effects of this gene variant… and look at how much work they do!  Some caveats:

  • The Amish eat a LOT more than we do.  Less vigorous exercise and less consumption of food would probably do the same thing.
  • Amish communities are more inbred than the population as a whole (Imagine that if you have a population of people who will only marry people from that same population… even if nothing normally considered to be ‘inbreeding’ is occurring, the population will eventually all sort of homogenize due to gene sharing within the constrained population and get generally the same sets of genes.  (on an aside, its interesting to see how different journalists try to delicately step around this very important issue… this article refers to it as genetic ‘purity’))
  • Because of this interrelatedness, its incredibly hard to tease out whether this effect is due to this gene and this gene alone, or whether there are other variants in the population that predispose people… for all we know, a large fraction of the Amish population they looked at has another gene variant that causes them to gain even MORE weight on average, so their vigorous exercise is fighting the effects of multiple bad genes, when most of us only have to deal with one.  A good control would be to put non-amish individuals on an amish diet and amish lifestyle and monitor the results after a year or so.  I understand why this might be hard to do, though.

So, in conclusion… no, odds are you *don’t* have to become Amish in order to fight off the effects of the FTO variant… but yes, of course, exercise in general helps… which I think we all know!

Look for another update later this week!

Amish data: The Amish, body weight, and exercise.  American Journal of Cardiology

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Responses

  1. genetic purity–lol. gotta love it! that’s alot of walking… i feel like alot of things (ads? maybe) say aim for 5,000 steps a day! we’re sedentary fools, i suppose, not being amish and driving cars 🙂

  2. Hehe. Guess we all have to become Amish! Or, I suppose, we could go the move-more-eat-less route…

    I wonder how much money gets wasted on pointless studies every year.

  3. Two thoughts: first, man I need to get rid of my car and walk more. Second, genetic purity!

  4. Sagan-

    I will look for and post something I saw a while back that documented just that… studies on the flow rate of ketchup at the like…

  5. Ha ha! I finally read this – thank for the dose of critical thinking! 🙂
    I’m glad that we don’t have to become Amish, because I wasn’t ready to get busy with my fam, ya herd?


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