Long-time Mt. Airy resident Josh Mitteldorf earned a Ph.D in astrophysics from the University of Pennsylvania but then switched fields to evolutionary biology.

By Rachel Freedman

Why do we get old and die?

Josh Mitteldorf pauses quizically as if he were considering the question for the first time. “It’s quite a paradox. Evolution is supposed to be all about making us strong and competitive so that we can have more children. So where does aging fit in? Aging actually DESTROYS fitness.”

Mitteldorf is a 30-year resident of Mt. Airy and an independent scientist. After earning a Ph.D in astrophysics from the University of Pennsylvania, he switched fields to evolutionary biology because he became intrigued with what he calls the “paradox of aging.”

“A lot of people assume that aging happens outside of evolution,” he observed. “Maybe we just wear out. Maybe the body is doing its best to keep its fitness up, but stuff happens. Well, that just turns out not to be true. We know because there are genes for aging — genes that actually orchestrate our self-destruction. Not only that, these suicide genes have been around a long, long time; they’re as old as the cell nucleus.”

For 15 years, Mitteldorf has been developing his evolutionary theory of aging. At first, the scientific community was dismissive, but in recent years, he’s started to get some traction. There are some prominent converts to what he calls “programmed aging” — the idea that aging and death are built into our genes by natural selection.

“I was drawn into the study of aging 15 years ago by a paradox: Lab animals that are starved live a lot longer than animals that are fed a robust, healthy diet. As a lifelong health food nut, I was dumbstruck; Could it be that the body responds to optimal nutrition just by destroying itself more efficiently?

“The question has taken me back to Darwin: If ‘fitness’ is supposed to be about fighting off your competition and leaving more children behind, then where does aging fit in? You would think evolution should have done everything possible to preserve the body against the ravages of age, but the puzzling fact is that we have genes with no other purpose than to kill us. Not only that, these genes have been preserved through eons of evolution. We know this because the same aging genes appear in worms and even yeast cells. Our bodies don’t wear out. They are gradually destroyed from the inside out, on cue, by a genetic program.”

Is there anything we can do to slow down the process of aging? In some respects, Mitteldorf’s answers are conventional and non-controversial: Keep the fat off. Exercise. Daily doses of baby aspirin. Where he differs from the mainstream is his robust view of the future of anti-aging medicine.

“Since aging is in our genes, there are targets ripe for pharmaceutical companies to attack. If aging is really controlled by chemical signals, then blocking those signals is something we ought to be able to do. I’ve told my daughters they should plan to live 200 years. ”

Trim and youthful at 62, Mitteldorf maintains a web site, AgingAdvice.org, which describes the implications for self-care that come out of his research on aging and evolution. “There’s good reason to believe that after thousands of years of fraud and charlatans, anti-aging medicine now has something real to offer. Anti-oxidants don’t work, but simple anti-inflammatories (aspirin, ibuprofen, fish oil) can add healthy and vital middle years. Vigorous exercise and weight control give us a few years more. And there may be more dramatic treatments to come.”

Mitteldorf will speak and answer questions this Saturday, May 28, 2 p.m., in the Meeting Room of Chestnut Hill Library, 8711 Germantown Ave. He has a book due out in the fall: “Suicide Genes: Why nature has arranged for us to die, and what we can do about it.”

More information at josh@mathforum.org.