Canadian preschoolers at risk of obesity as UPFs eat up nearly half of energy intake

High consumption of ultra-processed foods (UPFs) in Canadian preschool-aged children — especially males — is linked to increased obesity risk by age five, according to researchers at the University of Toronto.

“We saw that ultra-processed foods contributed to almost half of a child’s total daily energy intake,” says Kozeta Miliku, assistant professor of nutritional sciences at the university and researcher at the Joannah & Brian Lawson Centre for Child Nutrition.

Published in JAMA Network Open, the study claims to be the first to find sex-driven differences in the effects of UPFs on obesity risk among Canadian children.

A cohort study, which researchers say is Canada’s largest prospective pregnancy study, used data from 2,200 children.

The researchers are now investigating whether substituting minimally processed whole foods for some UPFs can help lessen the detrimental effects on body composition and the risk of obesity.

Dr. Ian Johnson, Nutrition researcher and Emeritus Fellow, Quadram Institute, reacted to the study saying the findings are “consistent with previous work suggesting an association between consumption of UPFs and obesity. It is interesting to see the link established at such an early age, although the study only seems to find a link in boys, not girls.”

“However, as with most such studies, and as the authors themselves seem to acknowledge, the general nature and poor specificity of the definition of UPF make it very difficult to establish any causal mechanism.”

Researchers are now trying to understand why males seem more vulnerable to health harms from UPFs and what role the gut microbiome plays. Males at higher risk

Zheng Hao Chen, a PhD student in Miliku’s lab, led the study, which found that Canada is one of the top consumers of UPFs globally.

UPFs are industrially produced and contain emulsifiers, preservatives, artificial colors, and flavors. Examples include soda, instant noodles, and chips.

The researchers examined data from food frequency questionnaires caregivers completed when a child was three years old and compared it to physical measurements when the child was five. The data specified height, weight, waist circumference, and skinfold thickness.

Miliku, also an adjunct assistant professor of medicine at McMaster University, stresses the importance of early childhood nutrition during development, as food habits and likes shape adulthood.

According to findings, UPF consumption at age three led to higher body fat measurements — BMI, waist-to-height ratio, skinfold thickness — and increased risk of overweight or obesity at age five.

Researchers are now trying to understand why males seem more vulnerable to health harms from UPFs and what role the gut microbiome plays. 

Eliminating UPFs? 

Miliku expresses that, as a mother who can not completely avoid UPFs, the food is accessible and handy for busy days. “We are all doing our best to make sure our children are fed, but there are opportunities for us to improve their diet.”

“Canada is falling behind in this area. With overweight and obesity affecting nearly one in three children in this country, it’s scary that we are not taking more action,” she shares.

Miliku hopes the study will spark regulators to create health policies, such as front-of-package (FOP) nutrition labeling, to help consumers choose less processed options. We recently spoke with the Center for Science in the Public Interest, which lauded the FDA’s FOP effort but advocates for more impactful “high in” warnings used internationally.

“UPFs are common in today’s retail market, but they are not all easy to spot,” adds Chen.

Both researchers suggest the Nutri-Score label and food-specific taxes that have worked in other countries to lower UPF consumption. India is also doubling down on UPF consumption nationally.

However, Miliku recognizes that an increasing number of Canadian households are experiencing food insecurity, suggesting that this is why policy support is required to ensure affordability and accessibility. Nutrition Insight previously spoke to Crown-Indigenous Relations and Northern Affairs Canada about the nation’s food sovereignty programs in response to the Inuit nutrition crisis.

We also caught up with Ayana Bio, which states that UPFs can be made healthier with cultivated plant cells.