Endocrinology Expert Witness Testimony Excluded in Dietary Products Litigation

Summary: Endocrinology Expert Witness not allowed to provide testimony as the defendant argued that the expert’s opinion that soy causes hypothyroidism has not been validated or tested.

Facts:  This case (LOVERDI et al v. MEDIFAST, INC. et al – United States District Court – Eastern District of Pennsylvania – May 15th, 2019) involves a products liability claim.  The plaintiff claims that she developed hypothyroidism from ingesting soy-based dietary products that are manufactured, marketed, and sold by the defendant.  In order to prove her claim, the plaintiff has hired Jonathan Williams, M.D., M.MSc (Endocrinology Expert Witness) to provide testimony.  The defendant has filed a motion to exclude this expert from testifying.

Discussion:  Dr. Williams opined that the plaintiff’s development of autoimmune-related hypothyroidism, along with her pre-existing risk factors, fit with the onset of her consumption of the soy protein-based products made by the defendant.  The court notes that Dr. Williams is qualified to form an opinion in the field of endocrinology.  The court notes that he is a board-certified endocrinologist at Brigham and Women’s Hospital and the Boston VA Healthcare System.  The court states that the defendant could not challenge Dr. Williams’ qualifications as an expert endocrinologist.

The defendant does attack Dr. Williams’ opinions as unreliable.  The defendant argues that Dr. Williams’ opinion that soy causes hypothyroidism has not been properly tested or validated and has not been submitted to peer review.  The defendant argues that his opinion goes against the overwhelming weight of the scientific evidence that demonstrates that there is no causal link between soy protein and hypothyroidism.

The court notes that Dr. Williams candidly admitted that there are no tests or studies that show that soy contributes to hypothyroidism  in those predisposed to the condition.  In addition, the court states that although Dr. Williams conceded that there has been no specific study involving at risk individuals, he did reiterate that research on soy and hypothyroidism with the at risk population still needs further study.  The court opines that Dr. Williams has no scientific or medical evidence to support his opinion and that there are no studies that establish a link between soy and hypothyroidism.

The court opines that Dr. Williams’ testimony linking the plaintiff’s hypothyroidism to her ingestion of the defendant’s products is not based on reliable medical and scientific evidence and is unsupported speculation.  In addition, the court opines that Dr. Williams cannot point to any reliable data that supports a casual link between soy-based foods and hypothyroidism.

Conclusion:  The motion to exclude the expert witness testimony of Jonathan Williams, M.D., M.MSc is granted.