New blood tests have recently been approved by the U.S. Food and Drug Administration (FDA) to help doctors distinguish Alzheimer’s disease from other types of dementia or unrelated conditions. These tests look for specific proteins in the blood that are linked to Alzheimer’s, such as amyloid and a type of tau called p-tau217. While they offer a less invasive alternative to brain scans, experts stress that the tests are not yet widely available or recommended for people without symptoms. Some labs and online services already offer similar tests, but dementia specialists warn that people without symptoms should avoid these tests unless they are part of a research study. A faster diagnosis of Alzheimer’s can be important for patients in early stages, as it may help them qualify for treatments that can slightly slow the progression of symptoms. However, research has shown that lifestyle factors can play a major role in delaying dementia. A large study found that people who avoided high blood pressure, diabetes, and smoking in their 50s were more likely to stay dementia-free for nearly 13 years longer than those with all three conditions. Experts recommend focusing on managing these preventable risks, as they can damage brain blood vessels and contribute to inflammation. Blood tests that detect p-tau217 appear to be especially effective in identifying amyloid buildup in people who already have symptoms. A recent study by researchers at Mass General Brigham found that older adults with very high levels of p-tau217 had a 38% risk of developing cognitive impairment within five years and an even higher risk over 10 years. However, a “positive” test result indicates a risk, not a certainty, that someone will develop Alzheimer’s. Many older adults have high levels of amyloid in their brains but never experience cognitive decline. While negative results are generally reliable, a positive result can sometimes be incorrect — known as a false positive. A major trial conducted last year showed that adopting healthier habits can slow age-related cognitive decline in older adults at higher risk of dementia. These habits included moderate exercise, resistance training, and following the MIND diet, which emphasizes foods like leafy greens, berries, whole grains, poultry, and fish. Dementia experts also recommend getting enough sleep, staying socially engaged, treating hearing loss, and keeping the mind active. They emphasize that middle age is a crucial time to focus on these preventive measures, as early intervention may significantly reduce the risk of developing dementia later in life.