Hair today may not be gone tomorrow

“You are what you eat, and clues to what people ate thousands of years ago are stored in their hair,” said Stephen Macko, professor of environmental sciences. A decade ago Macko began to analyze the hair of University students to discern their dietary habits, but for the last five years, his innovative analysis of ancient hair has taken him to the far reaches of the globe — and back in time several thousand years.

Macko has analyzed hair clippings from the Stone Age Iceman found in the Oetztaler Alps on the Austrian-Italian border, from the Coptics of Egypt, from the Late Middle Kingdom mummies of Egypt, and from the Chinchorro mummies of Chile. His most recent studies have included hair from an ancient baby found in a cave in the Andes mountains, some 1,500 to 2,000 years old and, in a study a little closer to home, hair from the head of George Washington.

“We cannot tell what kind of bread a person ate, but we can determine if they ate grains, or meat or fish or vegetables,” Macko said. The Ice Man, for instance — thought by some to be a hunter — was probably a strict vegetarian at the time of his death. George Washington, on the other hand, was a “a centrist,” according to Macko. “He didn’t eat a lot of corn, wheat, and beans, but he didn’t eat too much meat either.”

Macko claims that hair may be the best preserved part of the human body. He measures the stable isotopes contained in hair, and by observing changes in the amounts of carbon, nitrogen or sulfur isotopes, he can differentiate source materials, whether plant or animal, terrestrial or marine.

One of the first to analyze ancient hair, Macko said that researchers have traditionally looked to archaeology to offer clues about the dietary habits of ancient people.

Although hair studies are growing in popularity, most scientists do not possess the resources to perform ancient-hair analysis. “The isotope lab at U.Va. has been at the forefront of advancing this technology in the understanding of diet,” Macko said.