FDA Funds Bitter Orange Toxicology Study

June 21, 2011

The results are in.

Bitter orange extract (Citrus aurantium) is one of the most widely used (and widely criticized) ingredients in dietary supplements marketed for weight loss supplements. Now, an FDA-funded toxicology study on bitter orange and rats suggests the ingredient is for safe for maternal and fetal animals.

FDA researchers assigned pregnant rats to bitter orange extract or pure p-synephrine (the active component of bitter orange commonly linked to Ephedra) at doses of up to 100 mg/kg of body weight for 20 days. Supplementation began on day one of pregnancy.

Researchers found no indication of developmental toxicity in rats, even when bitter orange was combined with caffeine.

“We are very pleased to see an FDA study corroborate the safety of bitter orange and p-synephrine when used in combination with caffeine,” sand Bob Green, president of Nutratech Inc., supplier of the patented bitter orange extract Advantra Z. “In the past year, there has been an abundance of new research that continues to support the safety of bitter orange…The positive findings of this developmental toxicity study directly address these concerns.

Funding for the study was provided by FDA and the National Center for Toxicological Research. The study has been published in the May 2011 issue of Birth Defects Research Part B: Developmental and Reproductive Toxicology.