Two different studies contradict the correlation between copper and dementia. A US study on mice concluded that an excess of ‘free’ copper in the blood would favor the accumulation of beta-amyloid in the brain which is responsible for Alzheimer disease. Rashid Deane, lead author of the US study, explains that in the amyloid plaques typical of Alzheimer’s there is a high amount of this metal. A study at the British University of Keele published in the February issue of Nature, reaches a diametrically opposite conclusion in that a reduction in the level of copper in the brain may facilitate the deposit of amyloid-beta in the form of senile plaques in Alzheimer’s. The researchers analyzed 60 brains of deceased persons suffering from Alzheimer’s disease: all resulted in a lower amount of copper compared to that present in the brain of healthy individuals.What is certain is that the ‘free’ copper in the blood is highly toxic due to the oxidative stress that it causes.