We recently received two questions about sugar and, frankly, both of them surprised us. The first was from a reader who said she had looked everywhere to find the U.S. Department of Agriculture's recommended daily allowance for sugar and was totally baffled. The second question concerned a rumor that eating sugar removed other nutrients from the body.
In order to evaluate what we have to say about sugar, truth-in-advertising laws require us to admit that we both have a sweet tooth. So, having gotten that out of the way, we can now try to clear up some of the confusion.
Sugar belongs to the class of foods known as simple carbohydrates. Along with more complex carbohydrates, these all break down to glucose in the body, and glucose is carried by the blood to provide energy for cells. Any glucose that isn't needed by cells is converted into glycogen, which is stored either in the muscles and liver or as body fat.
*
There are dozens of types of sugars. Scientifically, they are called fructose (fruit sugar), glucose (also known as dextrose or corn sugar), maltose (malt sugar), lactose (milk sugar) and sugar alcohols, such as sorbitol and xylitol. Sometimes they are given names that reflect where they come from, such as honey, maple syrup and corn syrup.
It is hard to escape sugar entirely. It is everywhere: in the obvious places like candy, soft drinks and the sugar bowl. It also shows up where we might not expect it--in ketchup, frozen dinners, breads, canned goods, fruits, vegetables and dairy products.
Complex carbohydrates (which are primarily starches) break down to glucose just like sugar does. Starch is the means by which plants store energy in the same way that glycogen is the way humans store it. But it takes a little longer for complex carbohydrates to break down (because they are more complex molecules), and the bonus is that complex carbohydrates carry other nutrients along with the sugar.
When you get simple sugar in fruits and vegetables, you also get many other nutrients plus fiber. When you get sugar in a candy bar or a soft drink, you get nothing but calories. Well, maybe a little fat thrown in for good measure. As our reader already discovered, there is no RDA for refined sugar, not even a maximum recommended amount, like there is for sodium. But if you look at the very tip of the USDA Food Pyramid, you will find that sugar joins alcohol in a small space that says eat sparingly.
