Active retirement- scientists have still not cracked the secret to living beyond 90
With the New Year, the search for a fountain of youth has existed almost as long as man.
The Greek historian Herodotus, who lived in the fifth century BC, wrote about the long-lived Macrobians who drank from a magical African spring. American schoolchildren learn that the Spanish explorer Ponce de Leon stumbled on to what is today’s Florida while looking for a youth restoring elixir.
Modern medicine has managed to extend life expectancy greatly, but that statistic has been achieved largely thanks to fewer deaths during childbirth, municipal sanitation, safe drinking water and the arrival of antibiotics. Science has not yet cracked the secret to living beyond 90, though researchers have identified areas — dubbed “blue zones” — where people do live longer than most.
Recent research has focused on telomeres — the tiny ends of chromosomes, which like shoelace tips keep the chromosomes from being degraded but eventually shorten and allow cells to age. But while small studies have shown that lifestyle changes can increase telomerase — an enzyme that repairs telomeres — there is no easy way yet to make use of this information.
One important insight that has emerged in recent research is that your chronological age — how old you are — can be dramatically different from what scientists call your biological age. A study recently released by Duke University in North Carolina found that in a group of one thousand 38-year-olds who had been followed for 12 years, their biological age varied from 26 to 61.
How can that be? Biological age is determined by combining important biomarkers of health such as blood sugar levels, cardiorespiratory fitness, and measurements of fat and cholesterol to produce a single number representation of age. If your blood sugar levels are higher than average, for example, your biological age could be higher than your chronological age. Alternatively, if you are extremely fit, your biological age could be much lower. Scientists have yet to agree which biomarkers to use.
A start-up company based in Boston called InsideTracker is trying to commercialise this insight in a fascinating way. For $99, the company sells a test called InnerAge, which analyses a drop of your blood and identifies five biomarkers: blood glucose, vitamin D, C-reactive protein (a measure of inflammation), liver function, testosterone for men and the hormone dehydroepiandrosterone sulfate for women. It then offers ways to improve these numbers. “The InnerAge number is just an estimate, but it gives you a red light saying you need to take care of yourself,” says Gil Blander, chief science officer at InsideTracker.
The company says it has combed scientific literature to find food combinations that can benefit health concerns. In my case, for example, I had higher than optimum blood glucose, so the firm recommended eating high fibre foods.
Dr Blander acknowledges that the tests leave out biomarkers such as cardiorespiratory fitness and body mass index, which have been found by other researchers to be key to longevity. But he says that the firm is hoping to include such measurements when reliable measuring devices can be found.
In other words, they are concerned people will tell porkie pies about their weight or exercise regimen, confounding the algorithm. Are people that vain?