Taurine helped stave off death in laboratory animals, but researchers cautioned that the supplement is not a magic elixir.
Two scientists — one in a white lab coat, the other in a sport jacket — look at a screen that has blue and purple markings on it in a lab with a high-powered microscope on a table to their left.
A dietary supplement taken by fitness buffs could hold the key to a longer and healthier life, suggests a new study of mice, monkeys and worms. Researchers found that a high daily dose of taurine, an amino acid commonly added to energy drinks and naturally found in various foods, helped to delay death and mitigate against the biological ravages of aging.
Strength, memory and metabolism improved in the lab animals, according to the new study, published in Science. Inflammation and DNA damage were kept at bay. And middle-aged mice that regularly took taurine supplements lived significantly longer than those that did not.
Taurine — a nutrient produced by the body and obtained from animal-based foods like shellfish and turkey — has a long track record of safety, they said. But when ingested in large amounts it could cause digestive problems, kidney strain and potentially harmful interactions with medications.
Its effectiveness in promoting healthy aging in people is yet to be established — and other once-hyped anti-aging drugs that showed initial promise in mice and monkeys have not always panned out in human testing.
One small clinical trial in Brazil found that four months of low-dose taurine supplementation had positive antioxidant effects in older women, with no toxicity concerns. But larger and longer studies are needed to gauge the effectiveness of other doses of taurine, researchers said.
Human studies on taurine supplementation have generally tested low doses, typically around 1.5 grams per day. The mice and monkeys in the new study were given a dose equivalent to about three to six grams a day for humans — a level deemed safe by European regulators, but still on the higher end of the spectrum.
“The bottom line is that clinical trials need to be done,” said Vijay Yadav, a longevity researcher at Columbia University Irving Medical Center, who led the study.
Taurine got its name in the 1820s from the Latin word “taurus,” meaning bull, after German scientists first isolated the amino acid from the bile of an ox.
Dr. Yadav didn’t know anything about taurine, however, until around a decade ago, when he found that the supplement helped promote bone development in young mice born to vitamin-deficient mothers.
Studies on humans had already linked low taurine levels to poor heart health, cognitive performance and muscle function. Some research also points to taurine underpinning the extraordinary longevity of people living on the Japanese island of Okinawa.
But whether taurine deficiency was a driver of aging, or simply a byproduct of the aging process, remained unclear.
Dr. Yadav, together with colleagues at the National Institute of Immunology in New Delhi, first measured taurine levels in people’s blood and found a steady decline with age. In 60-year-olds, taurine levels were about one-third of those in small children.
His team then gave high-dose taurine supplements to middle-aged mice and rhesus monkeys and compared their health outcomes to animals that did not get the amino acid boost. Six months of treatment were enough to see improvements in bone density, sugar metabolism and immune function in the monkeys, while the mice showed these benefits and more.
The mice gained less weight, had stronger muscles, were less anxious and showcased multiple improvements on a cellular level, including a reduction in the number of so-called zombie cells, old cells that stop dividing but continue to wreak havoc on neighboring tissues. Taurine also increased the average life span of the mice by 12 percent for females and 10 percent for males. The supplement had a similar impact on worm longevity.
The researchers also found supporting evidence for the anti-aging potential of taurine in people by analyzing two data sets.