(KANSAS CITY, Mo.) -- They didn't have the temptation of fast food or cigarettes, and yet despite their presumed healthy lifestyle, scans of mummies from 4,000 years ago show one-third of them had clogged arteries, the primary cause of heart attacks and strokes.

Researchers at St. Luke's Mid America Heart Institute, trying to unwrap the mystery of heart disease, say their findings suggest a hardening of the arteries may not just be tied to smoking, overeating and being a couch potato -- it may be an inevitable part of growing old.

Other experts caution not to read too much into the mummy data, saying the current evidence is overwhelming that clogged arteries are not inevitable and can be prevented with a healthy diet and lifestyle.

These findings were published in The Lancet.

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