Your hair can reveal a lot about you: from the kind of food you like to eat to your socioeconomic status, according to a new study. By performing a simple hair analysis, experts may be able to assess health risks within a community.
The researchers from the University of Utah analyzed samples of hair collected at different barbershops and hair salons in 65 cities across the US. They found that people residing in lower socioeconomic regions appear to be getting their dose of proteins from corn-fed animals.
“Corn is a major component of most animals raised in concentrated animal feeding operations (CAFOs), including cows, swine, and poultry,” Dr Jim Ehleringer of Utah’s School of Biological Sciences, tells MEA WorldWide (MEAWW). CAFOs are large-scale industrial facilities that rear animals in crowded spaces for meat, eggs, or milk.
The hair-diet connection
The human body breaks down proteins in the diet into amino acids, which then leave their traces in the hair, thereby acting as diet records. For instance, those feeding on animals that are reared on corn feed, contain signatures that are distinct from animals that feed on legumes and vegetables. The method is called hair isotope analysis and can reveal the source of a diet.
In this study, researchers analyzed the amino acid traces: signatures of elements such as carbon and nitrogen. These signatures are isotopes, which are different versions of the same element.
The use of hair isotopes is not new. Earlier, researchers studied carbon and hydrogen signatures in the hair to learn about a person’s travel history, inspiring Ehleringer and his team to carry out the current study.
Ehleringer and his team collected hair samples of nearly 700 people from barbershops and salons. They gathered them from trash bins, pulling out a handful or two of hair. “We then sort into identifiable clusters representing individuals,” he says.
They observed that carbon isotopes correlated with the cost of living. From samples collected at Salt Lake Valley, they found that the signatures tallied with the price of hair cut. “We had not imagined that it might be possible to estimate the average cost an individual had paid for their haircut knowing [carbon isotope] values,” the authors wrote. Taken together, they found that the corn-fed diet signature was more prevalent in low-income areas.
They also found some links to obesity levels. The team collected Body Mass Index values from the driver’s license from particular ZIP codes and matched them with the diet, obesity, and cost of living. “Our study only describes a correlation,” Ehleringer explains, adding that it does not prove that a particular diet lead to health issues.
Researchers hope that the more objective hair isotope analysis finds a place in health surveys. It opens up avenues to assess dietary patterns, especially across different economic groups within the US. “Better public access to information is needed – our hope is that our study provides additional information so that the public and policymakers can make informed judgments,” he added.
Ehleringer, however, adds that the isotope analysis can “provide general information about broad patterns in diets of different groups. This is, of course, a major limitation, since stable isotopes do not describe the specific food that was eaten.”
The study is published in Proceedings of the National Academy of Sciences.