A new study has found a relationship between cortisol levels in our hair and prevalence of metabolic syndrome (a cluster of abnormalities that increase the likelihood of developing diabetes and heart disease). Here’s how the New York Times describes the study:
High levels of cortisol — the so-called stress hormone — have been associated with cardiovascular disease in some studies, but not in others. This may be because measuring cortisol in blood or saliva at one point in time may pick up acute stress, but it fails to account for long-term stress. . . . Now Dutch researchers have assessed cortisol levels over several months by analyzing scalp hair samples. . . . The researchers measured the cortisol content in hair samples corresponding to roughly three months of growth from 283 older men and women, average age 75. They also gathered self-reported data about coronary heart disease, stroke, peripheral artery disease, Type 2 diabetes, lung disease, cancer and osteoporosis. . . . Compared with those in the lowest quarter for cortisol, those in the highest quarter had about three times the risk for cardiovascular disease and diabetes.
In the actual paper, the researchers say little or nothing about “stress,” and if I recall correctly, the relationship between cortisol and stress can be complicated. But the research raises the possibility that we will someday identify reliable measurements of chronic stress over time. Of course, we may need more than just your hair. But in what I call the experiential future, such evidence—combined perhaps with other physiological, neurological, and psychiatric data—may enable us to make better assessments of chronic stress levels than we can now.
Better measurements of chronic stress could transform the way we measure damages in tort cases and measure punishment severity in criminal cases. Billions of dollars change hands every year based on difficult-to-verify assertions about pain and stress. Similarly, we adjust the severity of incarceration by changing the duration of sentences and pay almost no attention to the very different ways in which prisoners experience confinement. Measurements of stress levels could also help determine when an interrogation tactic constitutes torture.
Of course, forensic techniques encourage people to use countermeasures. In the cortisol-hair study, for example, one measurement was apparently affected by rates of shampooing while another was not. So I’m not suggesting there will be a silver bullet that solves all measurement problems. When evaluating the scientific research, however, it is important to remember just how bad we are at measuring stress levels now, despite the fact that we make such assessments every day. The technology need hardly be perfect to represent an improvement.