Healthy Canadian infants and toddlers are heavier and longer than the World Health Organization (WHO) Child Growth Standards (CGS) according to a new study by researchers at the Institute for Clinical Evaluative Sciences (ICES) and St. Michael’s Hospital.

In 2006, the WHO released universal CGS, intended to describe the optimal growth of children. The WHO Multicentre Growth Reference Study took place between 1997 and 2003, and included children from Brazil, Ghana, India, Norway, Oman and the USA, who were deemed to be free of health or environmental constraints on growth.

“Measuring a child’s weight and height is an important and routine aspect of monitoring early growth, but the WHO CGS may not reflect the growth of healthy Canadian children,” says Dr. Joel Ray, lead author on the study and a researcher at ICES and the Li Ka Shing Knowledge Institute of St. Michael’s Hospital.

The study published last month in Paediatric and Perinatal Epidemiology compared the WHO-CGS to the postnatal growth of 9,964 healthy Ontarian children up to 2-years-old between April 1, 2002 and March 31, 2013, including various feeding practices and maternal place of birth.

The study found:

• Canadian children were markedly longer than the WHO-CGS before 18 months, regardless of feeding practice.
• Canadian children had a higher 50th percentile weight at birth, and again, after 6 months.
• By age 2 years, the 50th percentile weight of Canadian males was 823 grams heavier than the WHO-CGS 50th percentile.

The researchers add that the differences in percentiles of weight, length and BMI of young Canadian children compared to the WHO-CGS, regardless of infant feeding practice may impact how the “normal” growth of Canadian children is interpreted.