Children exposed to second-hand smoke are more likely to face weight and metabolic issues, according to a new study from researchers at the University of Montreal, Canada, which concludes that smoking around young children may be just as harmful as smoking while pregnant.
Lead author Linda Pagani, a professor of psycho-education at the University and a researcher at the CHU Sainte-Justine, found that children whose parents smoked when they were toddlers were more likely to have a thicker waist and a higher body mass index (BMI) by the time they reached the age of 10.
She says some 40 per cent of children are exposed either sporadically or continuously to second-hand smoke in their own homes and that, by the age of 10, the children who had been exposed to smoke were likely to have waists that were up to three-fifths of an inch wider than their peers.
And their BMI scores were likely to be between .48 and .81 points higher.
“This prospective association is almost as large as the influence of smoking while pregnant,” Pagani said. “Everybody loves their children but sometimes we close our eyes to risk factors. We need to face these risk factors and stop this behaviour.”
Waist circumference in youth in particular, she said, has become an important risk factor for obesity-related diseases in adulthood — so the findings indicate that public health initiatives and parental sensitization aimed at reducing home-based second-hand smoke exposure during the critical early childhood years are needed.
Pagani believes women who are bold enough to smoke while pregnant will likely smoke after birth as well. And there are even more women who stop during pregnancy but revert to it after giving birth.
“We are looking at second-hand smoke where children live and play and sleep,” she said. “Most people smoke because they just can’t kick the habit. People rely on smoking for the psychological effects, the idea that it calms them down. That has to be rethought. There are other ways to calm down.”
For the study, Pagani used data collected from the Quebec Longitudinal Study of Child Development, a vast survey of children born across the province which allowed her to focus on the behaviour of 2,055 families.
Furthermore, Pagani believes the statistics linking childhood obesity to exposure to parents’ smoking may underestimate the effect due to parents under-reporting the amount they smoked “out of shame,” she said.
With those parts of the brain that regulate metabolism not as finely tuned as they should be, Pagani explained, those who were exposed to second-hand smoke will find themselves putting on weight easily. Too easily.
“If you have an unhealthy fat distribution before puberty, your chances of being obese are quite high for the rest of your life,” said Pagani. The study published in Oxford Journal called Nicotine and Tobacco Research is the first to look at the effect of second-hand smoke on unhealthy body fat distribution.
While the increase she found may not sound significant, it occurs during a critical period of development which signals that the weight gain could have serious long-lasting effects. The exposure to second-hand smoke, she says, could cause endocrine imbalances or affect immune, neuro developmental and cardiovascular processes.
Pagani has also studied links between household tobacco smoke exposure and anti-social behaviour in later childhood, as well as the connection with attention deficit/hyperactivity disorder.
“This is kind of a wake-up call,” she said, adding that it reinforces ongoing debates about smoking on terraces or about parents smoking in a car with children.
“Yes, it is our business, these are public health issues,” she said. “And in a system like ours, where taxpayers support the health system, I’m interested in any risks that can be controlled. It’s important.”
Courtesy: Montreal Gazette