Is switching from sugar to artificial sweeteners a good trade? Dr. David S. Ludwig answers that question in the December 2011 issue of the Harvard Health Letter, which features eight Q & As by Harvard faculty and members of the Health Letter’s editorial board.

Most people consume artificial sweeteners to help them lose weight, and short-term studies suggest that they may have that effect, notes Dr. Ludwig, professor of pediatrics at Harvard Medical School and researcher at Children’s Hospital Boston. But other research raises concerns that artificial sweeteners actually promote weight gain. How so? These sugar substitutes are extremely sweet, Ludwig explains, so they may desensitize people to sweetness. As a result, nutritious, filling foods that aren’t as sweet — such as fruits and vegetables — may lose their appeal. Calories that were subtracted from the diet in the sweetener-for-sugar swap may sneak back in, in the form of refined carbohydrates and unhealthy fats.

“In addition, some recent research has identified sweetness receptors in fat tissue,” Dr. Ludwig says in the Health Letter. “We don’t know for sure, but that raises the possibility that artificial sweeteners could cause weight gain by directly stimulating the development of new fat cells.”

His research group at Children’s Hospital Boston is conducting a year-long randomized clinical trial looking at how artificially sweetened drinks affect weight and risk factors for heart disease in comparison with sugar-sweetened and unsweetened drinks.

Read the full-length article: "Ask the doctor: Are artificial sweeteners a good alternative to sugar?"