They might not be old enough for it to matter yet, and we might see numbers approaching that 67% as people live longer. https://www.nia.nih.gov/health/what-cau

They might not be old enough for it to matter yet, and we might see numbers approaching that 67% as people live longer. https://www.nia.nih.gov/health/what-causes-alzheimers-disease#risk https://www.nia.nih.gov/health/what-causes-alzheimers-diseas... "Older age does not cause Alzheimer’s, but it is the most important known risk factor for the disease. The number of people with Alzheimer’s disease doubles about every 5 years beyond age 65. About one-third of all people age 85 and older may have Alzheimer's disease." (emphasis mine) Perhaps if we beat cancer and cardiovascular diseases etc and see human lifespans reaching 100+ years old, we'll see close to 67% of people at that age get Alzheimer's.