TORONTO, June 13 ― New research has found that breastfeeding can have a protective effect against infants becoming obese as teenagers, even if they have a genetic predisposition for the condition.

Carried out by researchers at Mount Sinai Hospital and the University of Toronto, the new study looked at the genetic data and the body mass index (BMI) of 5,266 children in the UK to assess the impact of exclusively breastfeeding, and the duration of breastfeeding, on the BMI of the children from birth to 18 years of age.

The findings, published on Thursday in the journal PLOS Genetics, showed that when boys whose genes put them in the "high-risk” category for obesity reached 18 years of age, being exclusively breastfed until 5 months of age reduced their BMI by 1.14 kg/m2.

For girls, being breastfed brought an even bigger reduction of 1.53 kg/m2.

However, breastfeeding exclusively until 3 months of age, or receiving a mix of breastmilk and formula, did not cause the same reduction in BMI for children with a high-risk for obesity.

Breastfeeding has already been linked to many health benefits for both mothers and babies, including a lower risk of stroke, ovarian cancer, high blood pressure and heart disease for mothers, a lower risk of eczema, food allergies and diabetes for children, and a lower risk of weight gain for both mom and baby. However, the researchers point out that the reasons behind these benefits of breastfeeding are still not clear.

The World Health Organization recommends that mothers exclusively breastfeed their child for the first six months for optimal development and health. However, the team states that around only 40 per cent of babies are breastfed until this age, adding that the new study provides more evidence that exclusively breastfeeding for a longer period of time could bring health benefits for children and should be a priority for those who have a high risk of obesity.

"Obesity is a global problem that is causing a drop in wellness that is straining our health systems,” said author Dr Laurent Briollais. "Our study shows that while our genes do influence our risk of developing obesity, this predisposition is not irreversible and can be beneficially modified by exclusive breastfeeding.” ― AFP-Relaxnews