by Craig Weatherby
The authors of a British study found that children are more likely to become obese when their same-gender parent is obese.
When researchers from the Peninsula Medical School studied 226 families, they found that the daughters of obese mothers were more likely to struggle with weight problems.
Likewise, they found that the sons of obese fathers ran a higher risk of becoming obese (Perez-Pastor EM et al. 2009).
The authors did not find the same link between mothers and sons or between fathers and their daughters.
|Same-gender links were reversed in weight loss trial |
Therapists from the University at Buffalo enrolled overweight parents and children for a two-year program designed to help them lose weight together.
When parents and children tried to lose weight together, overweight children did better when the overweight parent was of the opposite gender (Temple JL et al. 2006).
And overweight mother-daughter pairs fared the worst.
Compared with overweight mother-son or father-daughter pairs, the participating mother-daughter pairs enrolled in the program consistently lost less weight.
These clinical findings seem to contradict the results of the population studies conducted in the UK and Australia, as summarized in this article.
Their research showed that the risks of obesity among eight year old girls were 10 times greater if their mother was obese. With boys, the risk of obesity was six times greater if their father was obese.
And compared to the apparent influence exerted by the weight of their same-gender parent, the weight of the children measured at the age of eight bore no significant relationship to their birth weight.
These findings suggest that childhood obesity is not primarily caused by genetic traits passed down by same-gender parents.
As the authors wrote, “Childhood obesity today seems to be largely confined to those whose same-sex parents are obese, and the link does not seem to be genetic. Parental obesity, like smoking, might be targeted in the interests of the child” (Perez-Pastor EM et al. 2009).
This finding seems important because it may mean that parents can reduce their same-gender child’s risk of obesity by losing weight themselves.
Australian study found similar links
The new UK study affirms the findings of prior Australian research, which found that the body mass index of parents predicted the body mass index of their children at the age of 18.
And over the course of the 9 year survey, the BMIs of both sons and daughters were consistently higher in offspring with an overweight or obese parent of the same gender.
After controlling for influences no weight gain, they Aussie team found that the body mass indices (BMIs) of 18-year-old sons and daughters resembled their mothers' and fathers' BMIs. (Burke V et al. 2001).
The BMIs of parents accounted for 48 percent of the weight-variance in daughters, and 33 percent of the weight-variance in sons.
Being physically fit at the ages of 12, 15, and 18 seemed to reduce a child’s risk of obesity.
As in the UK study, having a high birth weight did not predict that a child would become overweight or obese by the age of 18.
- Burke V, Beilin LJ, Dunbar D. Family lifestyle and parental body mass index as predictors of body mass index in Australian children: a longitudinal study. Int J Obes Relat Metab Disord. 2001 Feb;25(2):147-57.
- Perez-Pastor EM, Metcalf BS, Hosking J, Jeffery AN, Voss LD, Wilkin TJ. Assortative weight gain in mother–daughter and father–son pairs: an emerging source of childhood obesity. International Journal of Obesity, Nature Publishing Group. 33, 727-735 (12 May 2009) doi:10.1038/ijo.2009.76
- Temple JL, Wrotniak BH, Paluch RA, Roemmich JN, Epstein LH. Relationship between sex of parent and child on weight loss and maintenance in a family-based obesity treatment program. Int J Obes (Lond). 2006 Aug;30(8):1260-4. Epub 2006 Feb 21.