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Not a good article. I have been around the Tarahumara. The women are friendly but very shy, the men are not to be seen when outsiders are around. My guide told me that they have a 50% infant mortality.

However, their history is very cool: when the Spaniards were enslaving everyone they could catch in northern Mexico for a short and harsh life in silver mines, the Tarahumara did not like what they saw, and headed for remote areas.

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"My guide told me that they have a 50% infant mortality."

This would explain "the secret of longevity and perpetual health" - quite literal survivorship bias.

From http://www.lehigh.edu/~dmd1/art.html (just somebody's term paper I found on Google):

The Tarahumara are not very hygienic to even modern day indigenous standards. They are not very cleanly and the washing of their clothes is usually either an annual or semiannual tradition. The Tarahumara have no regular sleeping habits and simply go to sleep whenever and wherever they are tired and feel that they need rest. The practice of childbirth is also distinct to the Tarahumara. When a woman feels that it is about time for her to deliver the baby she will go off by herself into the wilderness, brace herself between two small trees and attempts to have the baby safely. There is a very high infant mortality rate among the Tarahumara. This fact is counterbalanced by the fact that there is also a very high birth rate. The average Tarahumara woman gives birth to about ten babies hoping that three or four will survive into adulthood. Adulthood is usually short for the Tarahumara with the average life expectancy being forty-five (Lutz 50). These factors are believed to help the Tarahumara survive as a race.

Perhaps the reason they have low incidence of diabetes, cancer, and heart disease is that these ailments often set in after the age of 45?

It depends on how they computed average life expectancy. Due to high infant mortality, life expectancy of survivors can be in fact much higher.

"Life expectancy is heavily dependent on the criteria used to select the group. For example, in countries with high infant mortality rates, the life expectancy at birth is highly sensitive to the rate of death in the first few years of life. In these cases, another measure such as life expectancy at age 5 (e5) can be used to exclude the effects of infant mortality to provide a simple measure of overall mortality rates other than in early childhood."

http://en.wikipedia.org/wiki/Life_expectancy

If you are correct then the previous quote saying a woman would give birth on average 10 times, expecting 3 or 4 to survive, then wouldn't the e5 be around 90? That's far better than in almost all developed countries...

I know of no research linking survival of un-aided birthing and a lack of neo-natal care to immunity from heart disease in old age. This isn't survivorship bias. It's a separate issue.

I'm not aware of any such research either, yet the possibility that people which would later in life develop serious illnesses have higher chances to die as infants in harsh conditions does seem like a plausible explanation of apparent better health of the surviving population.

A survivorship bias would not explain the effects of the diet and exercise regimen on the author, a seemingly average American male of Irish-Italian descent.

This is orthogonal.

One guy getting in a better shape after diet and exercise is quite expected.

Whole society being virtually free of big bad diseases is, on the other hand, extraordinary claim:

"When it comes to the top 10 health risks facing American men, the Tarahumara are practically immortal: Their incidence rate is at or near zero in just about every category, including diabetes, vascular disease, and colorectal cancer."

This sounds quite dishonest if what mark_l_watson said indeed holds. You could then equally say:

"When it comes to #1 health risk facing Tarahumara men, Americans are practically immortal: almost all their babies survive."

A man being able to run a super-marathon through a desert within months of switching to their diet and exercise regimen is hardly orthogonal. =)