Hair analysis reveals what you eat and how much you earn

The chemistry of our hair can reveal what we eat and even how expensive our hairdresser is: the analysis of the amino acids that make up the stem allows us to trace the foods we consume daily, revealing our socio-economic status and even the risk of obesity . The researchers of the University of Utah have discovered this, suggesting that they take advantage of this sort of biological diary that we carry in our heads to evaluate the health conditions at the population level. The results of the study are published in the journal of the American Academy of Sciences (Pnas).

The research was conducted on the hair of nearly 700 people, recovered from the bins of barbers and hairdressers in 65 US cities. Some samples were also collected in different areas of the urban area of ​​Salt Lake City. The results of the analyzes show that the chemical composition of the hair correlates with the cost of living in the different areas. "We didn't think it was possible to even estimate the average cost of the hairdresser based on the values ​​of the carbon isotopes," the researchers write.

Residents of less wealthy areas have larger amounts of a carbon isotope in their hair that comes from farmed animals fed on corn. By crossing the data with the information on body weight contained in driving licenses, the researchers observed that the isotopes present in the hair are also linked to the rate of obesity, highlighting possible connections between diet, socio-economic conditions and health.