A University of Minnesota study has reported that diacetyl (DA), a food additive used to mimic butter flavors, allegedly “intensifies the damaging effects of an abnormal brain protein linked to Alzheimer’s disease,” according to a recent American Chemical Society press release. Swati More, et al., “The Butter Flavorant, Diacetyl, Exacerbates β-Amyloid Cytotoxicity,” Chemical Research in Toxicology, August 2012. After noticing that the structure of DA resembles a substance “that makes beta-amyloid proteins clump together in the brain,” researchers apparently sought to determine whether the food ingredient could also cause the clumping described as “a hallmark of Alzheimer’s.”  

Their results evidently showed that DA at occupational exposure levels not only increased levels of beta-amyloid clumping but “enhanced beta-amyloid’s toxic effects on nerve cells growing in the laboratory.” Further experiments also suggested that DA “easily penetrated the so-called ‘blood-brain barrier,’ which keeps many harmful substances from entering the brain” and “stopped a protective protein called glyoxalase I from safeguarding nerve cells.”  

“We have now shown that DA potently enhances beta-amyloid toxicity toward neuronal cells in culture at concentrations that are normally found in body compartments upon occupational exposure,” concluded the study’s authors. “Whether toxic levels of diacetyl are achieved in various body compartments upon mere (over)consumption of DA-containing food substances is an unanswered but an important question… In light of the chronic exposure of industry workers to DA, this study raises the troubling possibility of long-term neurological toxicity mediated by DA.” See American Chemical Society Press Release, August 1, 2012.