Senescense: An elderly couple sits on an old bench watching the sunset amidst a brilliant colorwash of fall foliage — a moment of denouement most people hope to someday live.

In the search to prolong those “golden years,” scientists say glucosamine may provide an over-the-counter elixir for longer life. Previous work on longevity found a five percent gain in roundworms with an impaired ability to metabolize carbohydrates, which allows for the greater metabolism of amino acids in an effect mimicking the trendy low-carb diet. An abundance of nutritive sugar had shortened the lives of roundworms, as shown by experiments conducted in 2007 by Michael Ristow of ETH Zurich.

Yet researchers failed to replicate the results in experiments on rodents, prompting Ristow and his colleagues to study glucosamine, an over-the-counter arthritis drug shown 50 years ago to reduce the metabolism of nutritive sugars.

In this recent study, Ristow and his colleagues supplemented the diets of aging mice with glucosamine. Roughly equivalent in age at 100 weeks to a 65-year-old human, mice receiving the supplement experienced improved glucose metabolism for greater inurement to diabetes, a serious illness common among the elderly. Those mice receiving glucosamine as a supplement to a normal diet gained nearly 10 percent in longevity, the equivalent of eight human years.

Later analysis showed that glucosamine promotes the metabolism of amino acids in roundworms and mice, suggesting the supplement would mimic the effects of a low-carb diet for humans. The result “reflects the metabolic state of a low-carb diet due to glucosamine supplementation alone — while these mice ingested the same amount of carbohydrates as their unsupplemented counterparts,” Ristow said in a statement.

Most saliently, the researcher has begun to take glucosamine himself in the hopes of living a longer life. But will Ristow become the picture of Dorian Grey?

"Unlike with our longer living mice, such an association is no definite proof of the effectiveness of glucosamine in humans,” Ristow said. "But the chances are good, and since unlike with most other potentially lifespan-extending drugs there are no known relevant side effects of glucosamine supplementation, I would tend to recommend this supplement.”

Yet Ristow warns people with diabetes should tightly control their blood sugar for the first couple of weeks after beginning a glucosamine regimen.