What if you could live forever?

“It is a common belief that aging is inevitable and universal. Nothing could be further from the truth.”

That’s the eye-popping claim from the scientists Josh Mitteldorf and Dorion Sagan in their new book, “Cracking the Aging Code: The New Science of Growing Old — And What It Means for Staying Young.”

The book argues that humans don’t die because their bodies wear out or from disease, but because they’re programmed to die at a certain time for the good of the overall species. And — let’s face it, this is the part we really care about — there might be a way to un-program death. To do so, scientists must figure out which genes are deployed to kill us.

Mitteldorf, a trained astrophysicist, who comes to evolutionary biology as an outsider, believes that “aging clocks” — or “inner assassins” as he calls them — are programmed to kill us if we don’t succumb to disease or accidental death first.

At some point in the aging process, usually sometime after the seventh decade, this clock tells certain cells to go into a “senescent state,” which means that they start sending signals to the body that say “this is an old guy — it’s time to kill him,” says Mitteldorf.

How those clocks are programmed, and which genes carry out the suicide mission, is the key to the fountain of youth, he believes. If scientists can find the clock, and find the suicide genes, they can remove them or trick them into thinking their host isn’t old, thereby prolonging life indefinitely.

Mitteldorf found his controversial thesis thumbing through the pages of Scientific American 20 years ago.

The piece discussed the link between calorie restriction and a longer life span — a connection that’s been confirmed in studies on dogs, spiders, rats, yeast cells and lizards.

If life expectancy grows when food is in short supply, he thought, that must mean it shrinks when we’re well fed. Thus, we are programmed to die, he argues.

A programmed death ensures that the population dies at staggered rates as we age, which is bad for the longevity of the individual but good for the longevity of the community. But not every species has this arrangement with Mother Nature.

“Humans age gradually, but some animals do all their aging in a rush at the end of life, while others don’t age at all, and a few can even age backward,” they write.

Some lobsters, clams and sharks continue to grow larger, stronger and remain fertile with each passing year, showing no signs of aging until they die by disease or accident. The oldest clam on record is a quahog that’s been alive for 507 years and weighs over 700 pounds; in fact, it’s still alive.

Albatrosses and naked mole rats stay completely healthy their entire lives and then die from unclear causes at a predetermined time — about 30 years for naked mole rats, about 50 for albatrosses. There’s a certain type of jellyfish, dubbed the “Benjamin Button of the Sea,” that regresses back to youth after it reproduces.

Queen bees can turn their aging off, living for decades in a healthy hive, even though they have the same genetic makeup as the drones, which die within weeks from old age.

But animals have nothing on plants when it comes to longevity: An Aspen grove in Utah with a single root system is 80,000 years old.

“Nature can do whatever she damn well pleases when it comes to aging,” says Mitteldorf.

Scientists around the world are searching the animal and plant kingdoms for ways to hack nature with varying degrees of success.

Mitteldorf works with a team called the Gilgamesh Project. He estimates that within two decades they’ll crack the code.

At least six teams of scientists around the world, says Mitteldorf, are currently trying to figure out how to kill the senescent cells that start attacking us from within, usually after we hit 70 or 80. “Senescent treatments could appear on the market any day now,” he says.

There are also treatments that target telomeres, the sequences at the ends of chromosomes that get shorter every time the cell divides. You can also think of telomeres as a kind of clock that dictates how old cells are — and when it’s time to go into a senescent state. There are currently a host of supplements on the market that claim to help trick the body into extending telomeres.

As of now, Mitteldorf says, most have marginal life extending effects.

Mitteldorf, who looks considerably younger than his 67 years, experiments with all sorts of anti-aging techniques. He follows a healthy lifestyle that includes healthy eating, minimal drinking, daily exercise and maintains a lifelong yoga and meditation practice. But he also tries some lesser known techniques: He fasts once a week as part of a modified calorie-restriction diet that somehow helps the body produce new T cells to fight disease.

He takes megadoses of vitamin D each day because the vitamin is associated with lower rates of cancer and heart disease.

He pops a baby aspirin to reduce inflammation and a small dose of melatonin, which has been associated with life extension in mice, each day.

He also does two minutes of vigorous exercise before meals to trick the body into suppressing the insulin spike that accompanies eating and accelerates the aging process.

Does his family thinks he’s nuts — exercising in short bursts before dinner? Fasting once a week? “Well, I’m divorced,” he says, jokingly.

On the other hand, he recently hiked the Grand Canyon with his 26-year-old daughter and kept pace with her, easily. “It’s my profession to be healthy, strong, and active,” he says. “And I love that.”

[nypost]