BBC–Health, reports that the proteins that cause mad cow disease may also protect against Alzheimer’s disease. These proteins are called prions.

The protein responsible for mad cow is a prion protein. Prions are naturally present in the brain. Some are good, others, like the mad cow prion protein, have devastating effects. Laboratory tests reveal that a unique property of ‘good’ prions is their ability to block the buildup of beta amyloid. It is thought that high levels of beta-amyloid, sometimes referred to as “Alzheimer’s plague,” is the cause for Alzheimer’s disease.

In the variant form of the naturally occurring prion, Creutzfeldt-Jakob disease (vCJD), it is believed to be the cause of the human form of mad cow disease. The variant form infects the normal prions and causes them to change shape, which is what causes brain damage and ultimately death.

What research shows is that when the ‘good’ prions are present the amount of beta-amyloid is low. They proved this by looking at mice genetically engineered to lack the ‘good’ prion proteins, which showed high beta-amyloid levels.

The question that remains is what effect aging has on the ability of the ‘good’ prions to protect against Alzheimer’s disease.