For the past decade, researchers have been looking at what role testosterone levels play in prevention of Alzheimer’s disease. Recent studies have shown that low testosterone may increase a man’s risk for developing age-related dementia. What causes this? A build up of a protein called amyloid is a contributing factor to Alzheimer’s disease. Amyloid is a protein found naturally in the human body, but when sex hormone levels drop, amyloid levels can increase to a toxic level causing damage to nerve cells, which can lead to dementia-related diseases. This may be why Alzheimer’s is more common later in life, when a man’s testosterone levels commonly decrease. You can read more testosterone and Alzheimer’s Here and Here.