Statement of Kenneth Litwak, D.V.M., Ph.D., Associate Director of Laboratory Medicine:
A new University of Utah study that determined the amount of sugar that is toxic to mice cannot be equated to what will happen in humans. The study was also cruel to mice and unnecessary to further human health research, as the deadly effects of sugar on humans have already been well-documented using human population studies.
For example, a recent study using data from 350,000 people in eight European countries found that every extra 12-fluid-ounce serving of sugar-sweetened drink raises the risk of diabetes. Globally, diabetes caused 4.6 million deaths in 2011.
The University of Utah study on mice, on the other hand, does not apply to the human condition, since they just replaced 25 percent of the calories with sugar. Effectively, what they did was replace lunch with sugar, an unlikely human scenario.
To conduct this irrelevant study, the experimenters collected blood from the mice by retro-orbital bleeding: sticking a glass pipette into the eye of an unanesthetized mouse to collect blood, which is very painful and often results in blindness. In my experience as a animal researcher, this was done with anesthetized mice.
Earlier this year, the National Institutes of Health made a decision to end experiments on chimpanzees, for both ethical and scientific reasons. It is time to realize that the same considerations apply even to the smallest animals, such as mice and rats.
Founded in 1985, the Physicians Committee for Responsible Medicine is a nonprofit health organization that promotes preventive medicine, conducts clinical research, and encourages higher standards for ethics and effectiveness in research.