Ancient Arteries

This one is old news, but I only just found out about it.

We are told that heart problems are a modern lifestyle disease caused by rich food and lack of exercise. There is even a "peleo" diet fad urging us to eat like ancient hunter-gatherers. But now it seems ancient mummies show just as much artery clogging (aka atherosclerosis1) as modern people -- even though many of them seem to have had healthy "natural" diets and active lifestyles.

These studies use computed tomography (CT) scans of the whole mummified body to look for calcium deposits around arteries. Initial research was done on Egyptian mummies and found atherosclerosis to be common -- but this is hardly surprising among wealthy aristocrats, whether modern or ancient.

The real surprise is that more recent work published in The Lancet finds similar results in naturally preserved mummies from varied societies around the world, including hunter-gatherers. In addition the famous neolithic mummy of Ötzi the Iceman has similar calcium deposits.


Jo Marchant and Nina Lincoff have good posts on the topic, and Daniel Weiss has an even better one (which also has best title). Do read some or all of them, but I want to concentrate on what this means for lifestyle, paleo diet and all. First some cautions about the results

  • We can question whether the deposits seen in CT scans really show atherosclerosis. The diagnosis comes from experienced surgeons using their their eyeballs. My inclination is to trust those doctors, but it is still possible that some aspect of the mummification process is fooling them.

  • We shouldn't make hasty assumptions about lifestyle. For example, the hunter-gathers in the Lancet study were from the Aleutian Islands. Their diet was allegedly healthy because it was "marine based", but I guess those guys ate a lot of blubber and not many veggies.

  • Even if lifestyle wasn't the cause of heart disease back then, it might be now. As Crystal Phend writes, "Different risk factors, same disease". Atherosclerosis is an effect of inflammation -- an immune response. So maybe while we are prone to it because of lifestyle reasons, ancient peoples were prone to it because their immune systems had to work harder than ours.

In spite of these uncertainties, my own leaning is towards the happy-go-lucky interpretation, especially as concerns diet. Not only are humans omnivores, but our ancestors lived in a wide variety of ecological niches, and survived with many distinct cuisines, not all of which were nutritionally "balanced".

Moreover, heart attacks rarely kill people younger than fifty -- a venerable age by ancient standards. Evolution would have had little reason to select against such death, so we should not be surprised to find precursors like atherosclerosis in ancient humans.

  1. Don't forget! Atherosclerosis is sort of, but not quite, the same thing as Arteriosclerosis. (This sort of thing is why never dared study biology.)