A new Stanford Medicine study analyzed the levels of around 3,000 proteins in the blood of 44,000 people to assess the biological (as opposed to chronological) age of 11 of their organ systems, including the brain, heart, lungs, liver, and kidneys.

The biological age of the brain turned out to have the strongest link to future health outcomes.

Over a 15-year stretch, people with notably biologically aged brains were 300% more likely to develop Alzheimer's disease and had a 182% higher risk of death. That's because the aging brain is linked to neurodegeneration, inflammation, and reduced resilience across other organ systems.

In contrast, those with youthful brains slashed their risk of death over the same time period by 40%. 

I've dedicated my life to determining the most effective antiaging steps you can take, and to exploring cutting-edge research that enhances longevity — such as therapeutic plasma exchange.

My favorite ways to prevent premature brain aging are:

1. Ditch red and processed red meats and added sugars for a plant-based diet rich in healthy fats.

2. Get 10,000 steps a day or step equivalents, and do two strength-building workouts every week.

3. Cultivate a posse and embrace a purpose. Keep learning and find meaning in what you do every day.

4. Manage stress with a posse, purpose, and play. And add speed-of-processing games, meditation, and a healthy sleep routine.