Wishful science from obesity experts

Studies coming out of our universities and medical schools are misleading the public about the causes of, and solutions to, rising weight gain.

Over the past few months there have been two Canadian studies, one from the University of Waterloo and the other from the University of Toronto, recommending a tax on sugary drinks. The Waterloo study claims a 20-per-cent tax on sugary drinks would save 13,000 lives over 25 years along with untold levels of decline in cases of hypertension, diabetes, heart disease and cancer while saving the health-care system billions.

The Waterloo model assumes that a tax will lower consumption a few calories a day. At the end of 25 years we’ll all collectively lose enormous amounts of weight. That’s not science, that’s wishful thinking verging on quackery. People don’t behave that way; change one variable — by imposing, for example, a tax increase — and unintended consequences will surely follow, frustrating the most well-intentioned government policies.

This study also claims that if taxes worked in decreasing smoking levels they’ll work for sugar consumption. Anyone who can’t see through that false analogy isn’t thinking. How about this for a contradictory take? One study by National Bureau of Economic Research found that the strongest explanatory variable for weight gain has been a rapid decline in smoking levels among adults. But you’ll never see that theory tested in any Canadian university.

It might also have escaped some of these researchers that per capita sugar consumption has been dropping for years without government intervention.

Aside from calling for a mind-boggling level of government intrusion in food labelling and restrictions, nutrition scientists at the University of Toronto are also calling for a tax on sugary drinks. This is after consulting with 70 non-governmental organizations from over 44 universities. Put that many experts together and you’re sure to come up with some lousy recommendations.

Researchers who follow the literature on obesity quickly find themselves waist-deep in contrasting theories of what causes weight gain. Crazy as it may seem, we still don’t know why countries around the globe have been steadily putting on weight over the past few decades. Theories range from advances in food technology, less exercise, rising incomes, urban design, too much fat, too little fat or chemicals in the environment. Even global warming gets blamed.

What we do know is that once we put on too much weight it is almost impossible to take it off; hence the terrible record of diets on the market.

But the most egregious claim of these studies is that because other countries are intruding in the food market, Canada should follow suit. France, Hungary, Mexico and a few U.S. cities are experimenting with higher taxes on junk foods and sugary drinks. Here’s the truth about all of them: there is no proof — none — that any regulatory policy or tax has had any effect on health outcomes.

We now have meta-analysis from the New Zealand Institute of Economic Research that confirms the truth: “The evidence that sugar taxes improve health is weak,” it reported last year. Weak is hardly the word. It’s non-existent.

Too many of these researchers hold that the food industry is the key culprit conspiring to make us fat. Tame that beast and we’ll be on the road to better health. It’s all nonsense, of course, given that Big Food has been with us for the past 100 years while weight gain has become a problem only over the past 30-odd years.

A worrying number of nutritionists and obesity experts have stopped being objective scientists and instead have turned to advocacy. They’ve fallen into the camp that believes it’s OK to stretch the truth as long as it’s for a good cause. Real science requires a level of critical-thinking skills that challenge all conventional wisdom. Precious little of that seems to exist in Canadian obesity studies.

When scientists and MDS put their names to shoddily done studies that push a political agenda rather than real science, it does no one any good, least of all the Canadian public. The latter deserve to hear the truth about how we are spending public funds.

The only saving grace is that the federal government has so far resisted the temptation to burden its citizens with a useless sugar tax. How long that will remain the case is an open question.

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