Markers of our aging

I thought I would point to this interesting piece in the New York Times about the search for some simple objective assay of our biological age, as distinct from our chronological age. We all know people who seems much older or younger than their actual age. Things like skin wrinkles or blood pressure are not a very useful indicator, because they can be confounded by factors unrelated to aging. Reliable biomarkers of aging could:

...tell us a lot about our current and future health. Tracking these indexes before and after starting a new diet or exercise program, for instance, might show you whether it was actually pushing off your decline and fall. Aging-rate tests could help scientists evaluate possible anti-aging compounds in humans without prohibitively long studies.

One study of older women age 65-69 found that 13 factors correlate with healthy aging, including the eye’s ability to pick out very lightly shaded images on white backgrounds, and the number of rapid step-ups on a low platform that subjects could complete in 10 seconds. A more promising approach is finding that a number of chemical tags on our DNA - epigenetic markers, which I have mentioned in previous posts - correlate with our biological age in a way that yields a signature of aging that is not changed by disease or ethnic background.

If this continuing research pans out, aging-rate tests may someday be standard in annual physicals, and tracking the results over time would offer unprecedented insights on health risks. But such tests also may well raise fractious privacy and social equity issues.

Insurers might demand that customers take them in order to set premiums for life and health care policies. The tests may also reveal how factors like exposure to environmental toxins and the stress of job loss accelerate aging, and by how much — fodder for lawsuits.

Some of us will be relatively short-lived, fast-aging “less fortunate,” and others will be long-lived, slow-aging “more fortunates,” predicted John K. Davis, a philosophy professor at California State University, Fullerton. And age discrimination will gain an entirely new meaning.