Laser beaming a hair can reveal breakfast details

The carbon you eat goes into your hair, so hair is a record of carbon ratios.

Updated: May 02, 2011, 20:35 PM IST

London: A new laser can tell what you had for breakfast by beaming on one of your hairs, a study says.

Researchers can even tell where a person has been by examining the chemicals which are in one`s hair.

Previous techniques had burned hair samples but the new method breaks them down instead and allows far more precise readings, reports the journal Rapid Communications in Mass Spectrometry.

Researchers hope that it could be used for forensic science or by biologists exploring ruins - in theory they will be able to find out far more about the diet of ancient fossils they find, according to the Daily Mail.

Standard chemical analysis involves taking samples and putting them in mass spectrometers, machines which weigh and identify samples.

Until now lasers have been used to create the tiny 50 micron-wide samples but they scorch them because the beam is too powerful.

A team from US Pacific Northwest National Lab (PNNL) got around the problem by using ultraviolet rays instead.

Lead researcher Jim Moran, geochemist at PNNL, said: "The carbon you eat goes into your hair, so hair is a record of carbon ratios. If you`ve been travelling, I could guess which countries you`ve been to or what you ate.

"With a single hair, we`ve shown you can take carbon isotope measurements over time instead of just chopping up the sample and averaging everything."

Currently the research is only looking at carbon in samples, but experts said that could soon expand beyond that.