As researchers, parents and pediatricians continue to grapple with the rising problem of youth obesity in Canada, a new study from the University of Waterloo suggests we may be overlooking one significant contributor to the problem — alcohol.
The study, appropriately titled "Estimating how extra calories from alcohol consumption are likely an overlooked contributor to youth obesity," found binge drinking among Grade 12 students could be a significant, yet misunderstood, contributor to the nation's obesity problem in teenagers.
"There are a whole bunch of things that prevention groups are focusing on when it comes to the obesity issue," U of Waterloo professor Scott Leatherdale, one of the researchers in the study, told VICE.
"They talk about sugar-sweetened beverages, fast food and fast food advertising, the food environments in the schools, and we just wanted to say 'hey, high school kids drink a lot more than people recognize in Canada' and alcohol is basically a sugar-sweetened beverage."
Binge drinking in Canada is generally defined as five or more drinks in one sitting for males, and four or more drinks for females.
Rates of obesity in Canadian youth is on the rise. According to the Childhood Obesity Foundation, from 1978/79 to 2004, the prevalence of overweight and obese kids aged two to 17 increased from 15 per cent to 26 per cent. That increase was highest among kids aged 12 to 17, with overweight and obesity more than doubling from 14 per cent to 29 per cent.
More than a quarter of the 10,144 students involved in the U of W study in Alberta and Ontario (27 percent) reported they binge drank once per month, consuming between 6,000 and 13,200 extra calories in a year (equal to about 1.7 kilograms or nearly four pounds of fat). For the nearly five percent of students who binge drank twice per week, the extra calories range from 52,000 to 114,400 every year—potentially as much as 33 extra pounds.
The study didn't track student weights or attempt to correlate it with alcohol consumption, but it does provide a snapshot of just how many extra calories teenagers could potentially be consuming, Leatherdale said.
Researchers were somewhat conservative in their calorie estimates. While the survey counted the calories contained in a range of alcoholic drinks, including beer, wine, spirits and coolers, Leatherdale said they didn't include added calories from whatever they were mixing with the alcohol, such as Coke, energy drinks or whatnot. Which as anyone doing the freshman 15 or sophomore 10 knows, that adds up.
The survey also only counted up to the lower limit of binge drinking (five drinks) to calculate the caloric intake, and Leatherdale said there are other studies suggesting when teenagers binge drink they're actually consuming upwards or 10 to 12 drinks per sitting.
"If we're looking at harms kids are doing to themselves, it's a huge problem we're really not paying attention to," said Leatherdale.
The study is the first of its kind in Canada to point to a link between alcohol consumption and excessive weight gain in youth. It is part of a nine year COMPASS research study into youth (Grades 9-12) health behaviours, funded by the Canadian Institutes of Health Research.
Its role is to study youth behaviours surrounding activities such as tobacco use, alcohol consumption, physical activity and drug use, and to assess how government policy and changes influence those activities.
Dr. Sean Wharton of the Wharton weight and diabetes management clinic agrees that alcohol is likely a misunderstood contributor to youth obesity and something that pediatricians should consider as part of their patient assessment and treatment programs.
"I think it's a missed energy source and we tend to miss it in adults as well. It's probably even more of a missed source in kids," said Wharton.
The fact that drinking isn't legal until the age of 19 is likely a major contributor to this oversight, he added.
"We don't want to address it because we don't want to have the admission that kids are drinking when they shouldn't be drinking, and they'd have to potentially admit this in front of their parents," he said. The Wharton clinic has treated an estimated 100,000 patients over the past decade and recently added a pediatric portion to the practice, which has seen about 1,000 patients in the past two years.
Wharton and Leatherdale both agree that while youth consumption of alcohol far predates the current obesity crisis, much like the consumption of sugary drinks and junk food does as well, the culmination of easily accessible and inexpensive junk food, a more sedentary lifestyle and other lifestyle and environmental factors have all culminated to worsen the problem.
"If you stop the alcohol consumption, will that decrease weight? I'm going to say no," said Wharton. "Do those calories factor in to weight gain? Absolutely. But stopping it doesn't necessarily stop the weight gain."
"We're not pushing any policy agenda," added Leatherdale when asked about how he'd like to see these results assessed by the medical community and policy makers. "We're just saying that if people are pushing all these other factors that can contribute to obesity, we think they're potentially missing a big contributor for this group of kids."
He said their next step at COMPASS is to track students throughout their high school years to monitor their weight and alcohol consumption patterns and try to determine if there is any correlation between the two.