Hair Clippings to Measure Dietary Health

Remember when haircuts were routine? Today, it seems, they’re a bit more special. The close contact they require makes it so. But new research also tells us that hair clippings from these close encounters can be valuable for dietary research. A team of researchers gathered up hair from barbershops and salons in diverse U.S. locations and found they held clues about variations in dietary health.

They published their findings in Proceedings of the National Academy of Sciences.

Insight from Carbon and Nitrogen Isotopes

The researchers collected samples from 65 communities in central and intermountain regions of the U.S. They also did more intensive sampling in 29 zip codes of the Salt Lake Valley of Utah. They drew upon prior research on the effect that different protein sources have upon carbon and nitrogen isotopes in human hair. Corn-fed, animal-derived proteins yield isotope profiles in hair distinctly different from the profiles resulting from plant proteins.

These researchers needed no food diaries. That’s a good thing, since those self-reports are notoriously unreliable.

What they found in the isotopes was evidence for patterns of corn-fed meat consumption that correlated with geography. In posh neighborhoods, their data pointed to less corn-fed meat and more plant-derived proteins. In downscale locations, they found more corn-fed animal protein. The authors note:

As fast foods are well established as a significant source of corn-fed, animal-derived proteins, it is not unreasonable to assume that a significant portion of the cornfed, animal-derived animal proteins come from meals eaten outside the home.

Presumptions and Objectivity

This study is quite appealing in many ways. For one thing it’s different from the steady diet of self-reported data on what we’re eating. Despite assurances from folks with vested interests in big databases of self-report, we need alternatives.

And hair clippings don’t lie. They just pile up on the salon floor – ready for analysis.

Is this approach a panacea? Hardly. For one thing, the humans who interpret the data it generates can still bring their biases to bear. Assumptions – such as these authors make about “fast food” – can lead us astray.

But any way you look at it, a fresh approach is refreshing.

Click here for the study and here for further reporting in Scientific American.

Haircut, photograph © Beth / flickr

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August x, 2020

One Response to “Hair Clippings to Measure Dietary Health”

  1. August 15, 2020 at 8:49 am, Mary-Jo said:

    Nice to have hair clipping analyses to corroborate, perhaps, data from dietary records, but, not take the place of food intake investigations. In my opinion, this is more a general commentary on CAFOs, which seem to have lately been exposed for their various drawbacks for a multitude of reasons, aside from sources of copious amounts of cheap mass-produced amounts of inferior quality meats full of excess hormones, now corn products, let alone high likelihood of untoward pathogens and contaminants, all for the ‘benefit’ of ‘affordable’ copious consumption to fill Americans up. It looks like sustainable, decentralized smaller, less ‘industrialized’ meat production plants may make a comeback and, hopefully, persons from every zip code are entitled to high quality meat products coming from them.