Interesting. I don’t believe her. I think her purpose was to suggest that weight is nearly as immutable under changes in diet and exercise as height.
Well, average height is also increasing in the population. Does that mean that you could be as tall as me, if you weren’t too lazy to grow?
Twin studies and adoptive studies show that the overwhelming determinant of your weight is not your willpower; it’s your genes. The heritability of weight is between .75 and .85. The heritability of height is between .9 and .95.
On the other hand, I do think there’s far more to appetite and obesity than willpower[1].
Are there people with genetics such that, had they been given a diabetes+obesity inducing diet as children, they would still be rail thin and fidgety, burning tons of calories without explicit exercise? I think there are.
But I expect interaction between environment and genes to be very high in obesity[2], so heritability can’t be used on its own to draw that conclusion.
[1] “studies of monozygotic and dizygotic twins have unambiguously shown that there is a much greater resemblance in the degree of obesity between genetically identical monozygotic twins”—http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=1119832 - this is evidence for genetic variation in obesity with nearly constant environmental factors (clearly the availability of calories is a prerequisite for obesity).
[2] Extensive fictional evidence exists in the rotund mother who tries to fatten up her offspring when they return for the holidays: “put some meat on your bones!”. Seriously,
Interesting. I don’t believe her. I think her purpose was to suggest that weight is nearly as immutable under changes in diet and exercise as height.
On the other hand, I do think there’s far more to appetite and obesity than willpower[1].
Are there people with genetics such that, had they been given a diabetes+obesity inducing diet as children, they would still be rail thin and fidgety, burning tons of calories without explicit exercise? I think there are.
But I expect interaction between environment and genes to be very high in obesity[2], so heritability can’t be used on its own to draw that conclusion.
[1] “studies of monozygotic and dizygotic twins have unambiguously shown that there is a much greater resemblance in the degree of obesity between genetically identical monozygotic twins”—http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=1119832 - this is evidence for genetic variation in obesity with nearly constant environmental factors (clearly the availability of calories is a prerequisite for obesity).
[2] Extensive fictional evidence exists in the rotund mother who tries to fatten up her offspring when they return for the holidays: “put some meat on your bones!”. Seriously,