#10 Rebuttal letter on Annurca Apple Extract for Hair Growth
Scott W. Keith, Andrew W.Brown, Moonseong Heo, Steven B. Heymsfield, and David B. Allison (2019) Re:“Annurca Apple Nutraceutical Formulation Enhances Keratin Expression in a Human Model of Skin and Promotes Hair Growth and Tropism in a Randomized Clinical Trial” by Tenore et al. J. Med. Food 22(12) 1301-1302.
This rebuttal letter, published in the same journal as the original research on Annurca apple extract for hair growth, presents critiques from five experts from the University of California and various research institutions. The paper is relatively short, spanning two pages, and focuses on two main concerns:
Key Highlights:
Flawed Randomization: The study did not randomly assign participants to either a placebo group or an active Annurca apple extract (AMS) group. The lack of a true placebo control group makes it impossible to distinguish the actual effects of AMS from other factors.
No True Double-Blinding: The investigators were aware of which patients received the placebo and which received the active treatment due to the non-concurrent placebo design. This knowledge could introduce bias in how patients were managed and how results were interpreted.
