Citing “carefully conducted” U.S. government studies, which purportedly found clear-cut evidence that aloe vera extracts caused intestinal cancers in male and female laboratory rats, the Center for Science in the Public Interest (CSPI) has listed the substance as one to “avoid” in its guide to food additives.

CSPI also noted that, when taken orally, aloe vera can cause cramps and diarrhea and has been banned in over-the-counter laxatives by the U.S. Food and Drug Administration since 2002.

Calling food and manufacturers’ claims that aloe has “powerful healing properties,” “balances stomach acidity” and detoxifies or promotes “overall well-being” unfounded, CSPI Executive Director Michael Jacobson suggested that consumers “save [aloe] for sunburns. Used topically, aloe vera is safe. But the fanciful health claims manufacturers are slapping on various drinks and pills are unfounded, so people simply shouldn’t expose themselves to the risks.”

Meanwhile, the International Aloe Science Council (IASC) issued a statement which claims that products made to IASC standards, using “decolorized” (purified) aloe are safe. “The powerful laxative effect from ingesting unpurified aloe vera products would make it obvious if that’s what people were consuming,” said IASC Executive Director Devon Powell. “Decolorized whole leaf aloe vera juice is devoid of the toxic chemicals that have caused so much concern, yet CSPI seems willing to make uninformed and sensational comments that will only serve to confuse and frighten consumers despite the facts.” See CSPI News Release, August 21, 2013; IASC News Release, August 23, 2013.