How Scientists Found Them

How do you even spot a longevity gene? You start with people who have already won the lottery: centenarians.

Researchers read the DNA of thousands of people who reached 100 and compared it to the general population, hunting for variants that turned up far more often in the very old. FOXO3 popped out this way across populations from Japan to Germany, which is why it's taken so seriously. The catch: even a standout variant shifts the odds only modestly. There is no single gene for a long life waiting to be switched on.

The Bigger Lever

So where does that leave you? Your genes set a rough range, but they rarely set the outcome.

The habits that protect telomeres, calm inflammation, and keep cells dividing cleanly are the unglamorous ones you already know: move often, sleep well, eat real food, and stay connected to people. You can't pick your DNA. You can pull the bigger lever.