Almost 7 million Americans ages 65 and older have Alzheimer's disease, and three-quarters of them are older than 75. But Alzheimer's doesn't just pop up once you start getting Medicare. It's a slowly developing disease that new studies show produces distinct changes in your brain and body over many years.

In 2020, researchers announced a blood test to spot biomarkers that signal Alzheimer's disease and allow for early diagnosis.

And recently, a 20-year study found that certain biomarkers in cerebrospinal fluid, which can be seen with brain imaging scans, appear in one time sequence in people who develop Alzheimer's disease and in quite another order in those who don't. They included markers for amyloid beta and tau proteins as early as 18 and 14 years before Alzheimer's diagnosis, respectively.

The good news is that taking steps while you're younger will reduce your risk for the development of those earliest Alzheimer’s markers.

Your goals? To maintain healthy blood flow, normal blood pressure, and healthy weight, manage stress, and prevent inflammation.

Start by eating a plant-based diet (may include fish like salmon); getting 150-plus minutes of exercise and 150 minutes of walking weekly; getting 7-8 hours of sleep nightly; having a posse of supportive friends; finding a passion that gives you a sense of purpose; and practicing speed-of-processing games.

There are 40 choices shown in at least two studies in humans to keep your brain functioning better. Options are listed in Dr. Mike's book "The Great Age Reboot" and at LongevityPlaybook.com.

You can do them in any order, just do them.