Toxic is a strong word with strong implications, even though it seems to be thrown around pretty lightly lately. For the purposes of physical health, a toxin is a poisonous substance that has an ill effect on the body. We all know that sugar is a source of empty calories and is said to promote cavities, but is it toxic?
That is the complicated question Gary Taubes tackled in his lengthy New York Times essay last Sunday.
Partly inspired by a 2009 lecture Robert Lustig gave called “Sugar: The Bitter Truth,” which was posted on YouTube (see on page two), the question has taken on a whole new legion of askers. And although it’s high-fructose corn syrup (HFCS) that has become Public Enemy #1, Lustig lumps both white granulated sugar (sucrose) and HFCS in the same messy, disease-causing bowl.
By the early 2000s, according to the U.S.D.A., Americans have increased consumption of sugar to more than 90 pounds per person per year. This increase happens to coincide with the current epidemics of obesity and diabetes. Taubes writes that in 1980, roughly one in seven Americans was obese, and almost six million were diabetic, and the obesity rates, at least, hadn’t changed significantly in the 20 years previously. By the early 2000s, when sugar consumption peaked, one in every three Americans was obese, and 14 million were diabetic.
Lustig’s argument is that sugar has unique characteristics, specifically in the way the human body metabolizes the fructose in it, that may make it especially harmful, at least if consumed in sufficient amounts. If this is true, it would mean that sugar is the likely culprit for several chronic ailments considered to be diseases of Western lifestyles—heart disease, hypertension and many common cancers among them.
As Taubes describes it, this means we can eat 100 calories of glucose (from a potato or bread or other starch) or 100 calories of sugar (half glucose and half fructose), and they will be metabolized differently and have a different effect on the body. The calories are the same, but the metabolic consequences are quite different….and ultimately, he ponders, may possibly be leading to cancer
I encourage you to read the entire essay, but in the meantime Taubes writes (spoiler alert!): the answer to the question of whether sugar is as bad as Lustig claims is that it certainly could be. It very well may be true that sugar and high-fructose corn syrup, because of the unique way in which we metabolize fructose and at the levels we now consume it, cause fat to accumulate in our livers followed by insulin resistance and metabolic syndrome, and so trigger the process that leads to heart disease, diabetes and obesity–and possibly cancer. They could indeed be toxic, but they take years to do their damage. It doesn’t happen overnight. Until long-term studies are done, we won’t know for sure. That said, Taubes notes, many of the researchers studying this question have removed sugar from their diet…
Robert H. Lustig, MD, UCSF Professor of Pediatrics in the Division of Endocrinology, explores the damage caused by sugary foods.