Popcorn Butter Linked to Alzheimer's?

MINNEAPOLIS — An ingredient used to make artificial butter flavoring for popcorn has been linked to alzheimer's disease.

The ingredient, diacetyl, is a chemical that's also been linked to respiratory problems in workers at microwave popcorn factories. 

In test tube studies at the University of Minnesota, researchers found the chemical lead to an increase in clumps of beta-amyloid. 

Beta-amyloid is a protein and marker of Alzheimer's disease in the brain.

The study results have not been shown in people.