Alzheimer's Archive

More than 30% of adults over 70 have amyloid or tau (proteins implicated in the development of Alzheimer's disease) in their brains yet have no apparent cognitive problems. This may indicate greater cognitive reserve, the brain's ability to compensate for damage.

Neurogenesis is the birth of new nerve cells, called neurons, in the brain. The ability to grow new neurons appears more prominent in super-agers, people 80 and older whose thinking and memory skills are as sharp as adults who are decades younger.

Many memory lapses are part of aging and don't signal Alzheimer's disease. Types of forgetfulness that usually aren't symptoms of dementia include forgetting names or details temporarily, misplacing objects but retracing steps to recover them, and occasional word retrieval problems. Signs of dementia include repeating questions and stories, getting lost on familiar routes, challenges with planning or solving problems, difficulty completing familiar tasks, new problems with words in speaking or writing, and withdrawing from social activities.

A 2025 study of over 5,600 women and men followed for over 30 years found that following a Mediterranean diet may reduce the risk of Alzheimer's disease and improve cognitive function. The effect is strongest in people who carry two copies of the Alzheimer's risk gene APOE4.

There are currently nine trials of vaccines for Alzheimer's disease under way. All of them are in people with mild Alzheimer's or with the pre-Alzheimer's condition called mild cognitive impairment. All of the vaccines are designed to encourage the immune system to remove protein deposits from the brain. Most experimental vaccines are given by injection; one being tested at Harvard Medical School uses a nasal spray. It will be several years before we know if any of them will work.

Researchers have found that the risk of death due to Alzheimer's disease is markedly lower in taxi and ambulance drivers compared with hundreds of other occupations. And the reason could be that these drivers develop certain structural changes in their brains as they work.

In a 2025 study of about 2,000 people (average age 80) who were followed for seven years, about a third developed dementia or mild cognitive impairment. Being socially active seemed to delay that diagnosis for about five years.