Study: Exposure to passive smoking during childhood is associated with risk of obesity

In a new study published in the Annals of Medicine, researchers show that exposure to secondhand smoke in children and adolescents is associated with an increased risk of overweight and obesity throughout life.[1].

A data collection over three decades

This study analyses data from two longitudinal studies conducted in Finland. The first involved 2303 children, boys and girls aged 3 to 18 years, followed between 1980 and 2011/12. The second involved 632 children aged 7 months followed between 1989 and 2009/10, with regular data collection. For both studies, parental smoking status was recorded to determine possible exposure to foetal second-hand smoke during pregnancy and parental second-hand smoke during childhood.

Exposure to passive smoking in childhood is a risk factor for obesity

At each follow-up, children's weight, height, and waist circumference were measured. These data were weighted for age, sex, socioeconomic status, birth weight, parental age, diet, and physical activity. When these covariates were taken into account, these studies show that the risk of overweight, obesity, and central obesity was higher in children with at least one parent who smoked, compared with those with nonsmoking parents. This association between exposure to passive smoking in childhood and obesity is observed throughout life.

Preventing tobacco use in the fight against obesity

Since smoking is one of the many causes of obesity, researchers point out that preventing its consumption would help combat this recent health scourge. According to the World Health Organization, obesity has nearly tripled worldwide since 1975. In 2016, 39% adults over the age of 18 were counted as overweight, or 1.9 billion people, as well as 38 million children under the age of five.[2].

[1] Johanna M. Jaakkola, Suvi P. Rovio, Katja Pahkala, Jorma Viikari, Tapani Rönnemaa, Antti Jula, Harri Niinikoski, Juha Mykkänen, Markus Juonala, Nina Hutri-Kähönen, Mika Kähönen, Terho Lehtimäki & Olli T. Raitakari (2020) Childhood exposure to parental smoking and life-course overweight and central obesity, Annals of Medicine, DOI: 10.1080/07853890.2020.1853215

[2] Obesity and overweight, World Health Organization (WHO), August 2020, consulted on 12/15/2020