[Paleopsych] BH: Middle Age Spread 50% Genetic

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Middle Age Spread 50% Genetic
http://www.betterhumans.com/Print/index.aspx?ArticleID=2005-01-20-1

Twin study shows why weight loss can be so hard for some

    Betterhumans Staff
    1/20/2005 12:40 PM

    Genes account for about 50% of adult-onset weight change, the gain
    that leads to so-called middle age spread.

    So found researchers from [8]Saint Louis University School of Public
    Health in studying sets of identical and fraternal twins who served in
    the military during the Vietnam War.

    In total, principal investigator [9]James Romeis and colleagues
    studied nearly 8,000 male twins. In early adulthood, more than 75%
    were of normal weight. Twenty years later, more than 55% were
    overweight or obese.

    Analyzing the data--identical twins share all their genes while
    fraternal share half--the researchers found that about 50% of the
    weight change was genetic. Environmental variables such as diet and
    exercise accounted for the rest.

    "We're not acknowledging the strength of genetic factors in our weight
    loss strategies," says Romeis. "You've got this genetic thing working
    against you that helps to explain why you're so heavy and why you may
    fail at diets and weight loss programs."

    For the participants in the study, weight gain appeared to hit at
    about 30.

    "Your behavior changes at 30; you become more sedentary," says Romeis.
    "At some point they tip into being overweight. Those who are
    overweight tip into becoming obese. It's slow, incremental change. At
    the same time, we didn't see much evidence that they lost weight
    during the same time period."

    The findings are reported in the journal [10]Twin Research ([11]read
    abstract).

References

    8. http://publichealth.slu.edu/
    9. http://publichealth.slu.edu/faculty/romeis.html
   10. http://www.australianacademicpress.com.au/Publications/Journals/Twin_R/TResearch.htm
   11. http://iris.ingentaselect.com/vl=1533029/cl=34/nw=1/rpsv/cw/aap/13690523/v7n6/s9/p596