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Please note that whilst I first heard of the cigarette smoking analogy from George Davey Smith, it originated long before this from Geoffrey Rose (Rose G. Sick individuals and sick populations. Int J Epidemiol 1985;14:32–38 (reprinted Int J Epidemiol 2001;30:427–32)). George has since pointed out that chance would also be a major factor in addition to genetics (Davey Smith G. International Journal of Epidemiology 2011;40:537–562)
Note from author: my statement "inactivity in children preceded increases in percentage body fat, but increased body fat percentage did not precede reduced physical activity"… is the wrong way around. It should read "inactivity in children did not precede increases in percentage body fat, but increased body fat percentage did precede reduced physical activity".
Apologies for this error and thanks to author of reference article Brad Metcalf for pointing it out.
Re: Are the causes of obesity primarily environmental? No
Please note that whilst I first heard of the cigarette smoking analogy from George Davey Smith, it originated long before this from Geoffrey Rose (Rose G. Sick individuals and sick populations. Int J Epidemiol 1985;14:32–38 (reprinted Int J Epidemiol 2001;30:427–32)). George has since pointed out that chance would also be a major factor in addition to genetics (Davey Smith G. International Journal of Epidemiology 2011;40:537–562)
Competing interests: No competing interests