Skip to main content

An apple a day is toxic.

At least, it is if you believe some of the health advice on the Internet. The maxim "sugar is poison, fructose is toxic" has garnered legendary pop-health status ever since Dr. Robert Lustig posted a video on YouTube about sugar's "bitter truth." Since then, sugar has been framed as the skeleton key that unlocks every physical malady. Scientifically, though, this might not be the case, according to Dr. David Katz of Yale University's Prevention Research Centre.

"An excess of sugar in the body is harmful, certainly – but so is an excess of oxygen, potassium, iron, water, or calcium," Katz writes, "too much of any of these can kill us – but just like the glucose that floats in our blood, so can too little." There are people living long, healthy lives all over the world who consume sugar in moderate amounts; a Mediterranean diet, he says, would hardly be complete without the occasional sticky slice of baklava.

I hate to be a stickler for semantics. Dr. Katz's argument isn't particularly earth-shattering. Nobody is saying that excess sugar isn't bad – it really is. If you needed reminding, too much refined sugar has links to obesity and other health problems. Katz's argument is simply one on behalf of balance, and a reminder that there isn't a singular thing that causes disease. This echoes Michael Pollan's warning against "nutritionism:" a cultural obsession with seeing food as a collection of micro-nutrients and buzzwords (think of the Oreos with "no trans fats" ) rather than as a whole-package deal.

The newly opened dialogue on sugar isn't a permission slip to eat cake every day, or to ditch everything you previously believed about healthy eating. It's just another indication that the world of health advocacy, particularly online, is a field dense with rhetoric, speculation and pathos. Squabbling back and forth about the finer points of a healthy lifestyle may suit physicians, gym rats and the scientifically literate, but it also stands to profit people who would rebrand unhealthy foods to make them seem healthy, at the expense of the vulnerable (low-income, low-education populations and children). Whether it's high-fructose corn syrup or "corn sugar," a rose by any other name can still do serious health damage, and Coca-Cola's "happy calories" have been linked to depression.

Ultimately, it's probably best to take all this sugar stuff with a grain of salt. Depending on your state of health, it might not be necessary to completely cut the fat, cut the sugar, cut out gluten or ditch meat – it might be enough to cut the alarmism.