Alzheimer’s disease is a common form of dementia that significantly impairs cognitive function and affects daily life, and it accounts for 60% to 80% of dementia cases. It involves progressive brain cell degeneration and is the fifth-leading cause of death for people over age 65 in the United States.

The main signs and symptoms of Alzheimer's disease include early short-term memory loss, worsening verbal memory, impaired problem solving, lack of motivation, depression, and sleep disorders. As the disease progresses, individuals experience further cognitive decline, motor function deterioration, and significant personality and behavioral changes.

Alzheimer's disease can only be conclusively diagnosed through an autopsy, but doctors can make a probable diagnosis based on symptoms, neurocognitive test performance, and ruling out of other causes. Recent PET scans can accurately identify amyloid accumulation, a key indicator of the disease, but are primarily used for research purposes.

No medical treatments have been proven to stop or slow Alzheimer's disease, but some medications, like acetylcholinesterase inhibitors, can improve symptoms and cognitive function to a limited extent. Additionally, aducanumab was approved by the FDA for its effects on amyloid plaques, though its effect on clinical outcomes is still uncertain.

Certain dietary patterns, particularly the Mediterranean diet, are associated with a lower risk of Alzheimer’s disease, whereas higher intakes of saturated fat and sugar may increase risk. However, these findings are based on observational studies, and there is a lack of randomized clinical trials to confirm causation.

Several supplements — including omega-3s, B vitamins, vitamin D, vitamin E, ginkgo biloba, alpha-GPC, lion's mane mushroom, ginseng, saffron, and sodium oligomannate — have been studied for their effects on established Alzheimer's disease. However, the evidence supporting their use is mostly conflicting or limited.

Exercise and physical activity can enhance physical function and cognitive abilities in individuals with Alzheimer's disease. Additionally, ketogenic diets and music therapy have shown potential benefits in improving quality of life and cognitive function, though results may vary.

The exact cause of Alzheimer’s disease is uncertain, but it is commonly associated with neurodegeneration and the accumulation of amyloid plaques and tau tangles in the brain. Additionally, various factors such as aging, depression, diabetes, and genetics are associated with an increased risk of developing the disease.