Children of moms who smoked or were obese are more likely to become obese adults

Obesity is considered to be a global public health concern, but experts still disagree about the precise origins and causes of rising obesity rates. One topic under debate is whether a person's individual genetics and behaviors are more or less important than environmental factors, like socioeconomic status, in developing obesity.

In the new study, researchers estimated the impact of several factors on a person's weight, including societal factors, like a person's job type, as well as early life factors, like a person's birth order, how they were delivered and whether their mother smoked or was obese. They looked specifically at whether a person was overweight, obese or severely obese at age 16 and age 42. They also looked at participants' weight between ages 16 to 42, a range that spans the rise in obesity rates in the United Kingdom. The data came from the 1958 National Child Development Study, a long-term study that followed the lives of more than 17,000 people born in a single week in March 1958 across England, Scotland and Wales.

The analysis showed that if a mother was obese or if she smoked, her child was more likely to be obese or severely obese at each of the ages examined. The findings demonstrate that these early life factors can have a persistent effect on a person's weight. Notably, these factors were just as powerful before and after the start of the rise in obesity rates in the UK, suggesting that the impact of individual factors, like behaviors, likely did not change during that time.

The results suggest that societal and early-life risk factors could be used to target obesity prevention programs for children and adults. The researchers also conclude that, since individual risk factors have not changed as obesity rates have risen, new studies are needed to identify societal factors that may have caused the current obesity pandemic.

The authors add: "Our research shows that the effect of maternal influences persists through to age 42 and that strikingly, those predictors were just as powerful (and prevalent) in the era before the current obesity pandemic began. This suggests that, as Geoffrey Rose pointed out, novel studies are needed of factors at the community/societal level that may have caused the current obesity pandemic, since individual-level risk factors appear not to have changed over the time period spanning the pandemic's onset and growth."