Unfortunately, cholesterol isn't the only substance washed out of the body by SPE. Because it acts as a fat does, SPE mixes with fat-soluble vitamins, such as A and E, in the intestines. And since the SPE isn't absorbed, these vitamins are not absorbed well either, the American Journal on Clinical Nutrition says.
Unfortunately, P&G's tests of olestra don't furnish convincing evidence of safety. For instance, in a test during which rats were fed SPE for two years, 48% of the males that were fed the highest dose died before the end of the experiment.
Among control animals, who did not eat the additive, just 28% died. In addition, groups of animals fed some doses of SPE developed pituitary tumors, leukemia or abnormal liver changes.
P&G scientists also observed reproduction in rats fed SPE for two generations. In one experiment, animals fed the highest dose of SPE gave birth to an unusually high percentage of stillborn young. Also, high-dose rats produced four abnormal offspring, including a fetus without eyes and a pup with a structural defect of the nervous system.
P&G denies that any of these findings are meaningful.