The Trouble with Fructose

But HFCS is only the tip of the sugar crystal. Sucrose is half fructose and half glucose.

Sucrose goes by a lot of names on the nutrition labels of the products that we buy in supermarkets and natural food stores. Probably no ingredient is more ubiquitous or goes by so many names as sugar. Sucrose includes white sugar, brown sugar, granulated sugar, turbinado sugar, and most of the sugar in regular and blackstrap molasses and almost all of the sugar in maple syrup. One of the trickiest names is “organic dehydrated cane juice.” I’m sure that it fools a lot of people into thinking they aren’t getting sugar. Sucanat is another name for dried sugarcane juice. So-called raw sugar includes demerara, muscovado, and turbinado. More than 100 different sucrose substances exist.

Even the natural sweeteners that I have been using occasionally have lots of fructose. From 90 to 97 percent of the sugar in agave nectar is fructose. Up to half of the sugar in some varieties of honey is fructose.

Even fruit, vegetables, and meat contain some fructose, both directly and as half of the sucrose in these foods. Among meats, corned beef and pastrami seem to have the most fructose, through their added sucrose content. But fruit, vegetables, and meat aren’t much of a fructose problem, because the total amount of fructose we get this way is minimal.

Between 1970 and 2003 our average consumption of fructose increased from less than half a pound per year to 56 pounds per year, according to the interview with Dr. Lustig. “We were never designed to take in so much fructose.”

Now we know why we need to avoid this added fructose in our diet. But let’s not go to extremes. Our bodies were designed to eat the fructose in fruit and vegetables. That naturally-occurring fructose is not the problem. The trouble with fructose is all the fructose and sucrose that we have been adding to our food.

Update: September 16, 2009: A correspondent just brought this video of a talk by Dr. Lustig to my attention. It's on YouTube at http://www.youtube.com/watch?v=dBnniua6-oM and well worth watching when you have the time.