WARNING TO pregnant women: Consuming coffee or tea may cause birth defects or other reproductive problems."
If the Center for Science in the Public Interest (CSPI) is successful in its petition to the Food and Drug Administration, that notice might appear on coffee and tea labels one day.
In addition to asking FDA to require such a warning notice, the citizen's group, which focuses on diet and health, asked the agency to begin an educational campaign about the hazards of caffeine aimed both at women and doctors. Cleft palates, heart defects, missing fingers and toes are some of the problems seen in animal studies.
According to the director of CSPI, Dr. Michael Jacobson, his group has "been urging FDA for years to warn women to minimize their consumption of caffeine. Because FDA has shown no real concern about this problem, we have taken the unusual step of communicating with 12,500 obstetricians/gynecologists and 1,500 midwives . . . . There is all benefit and no cost associated with this simple preventive measure."
Discussing 14 different animal studies regarding caffeine and reproduction, CSPI concluded the studies "have shown caffeine to cause birth defects in three different strains of mice at dosages as low as 50 milligrams per kilogram of body weight per day (50 mg/kg/day); in two strains of rats at dosages as low as 9 mg/kg/day; and in one strain of rabbit at 100 mg/kg/day."
Applying one of the criteria for extrapolating animal data to humans, the dosage equivalent of 9 mg/kg/day for mice would be 4 to 5 cups of coffee per day for a 100-pound pregnant woman.
Another criterion often used for extrapolating data applies a hundred-fold safety factor to the "no adverse effect" level in animals. Using this criterion, pregnant women should not drink more than a fraction of a cup of coffee a day.
In addition, CSPI presented seven human studies on the teratogenic effects of caffeine and observed: "The two best human studies indicate that caffeine causes birth defects and other reproductive problems."
Recently FDA's Dr. Thomas F. X. Collins reported that caffeine is teratogenic in animal experiments and concluded "there appears to be an insufficient safety factor (for humans) if various sources of caffeine are considered." Collins said the insufficient safety factor "could be a cause of concern."
Despite the current evidence, FDA has said it will not act on coffee or tea until it has finished its review of the safety of caffeine in cola beverages.
CSPI did not mention cola drinks, which contain substantial amounts of added caffeine because, the center said, it does not believe caffeine should be added to such products to begin with.