Yes.  I have no factual info for my impressions - you are right - maybe
people in the "third world" do not live long enough to develop cancer.

it is not true for peoples from the villacamba valley in ecuador , their
well none centenarians are free from cancer ,diabetes, heart diseases with a
diet far from being paleo and high in carbonhydates in form of corns ,tubers
and roots and othert grains ( quinoa ,millet etc...) yet they losse their
teeths at a very early age ( at 13 and 14 years old  most have lost their
front teeths and a lot older peoples have none left and have to eat mushy
foods ( that is one of the xplanation of their logevity as their digestives
system are spare too work too much.

< The most outstanding thing about the physical features of the people,
whether from the actual villages or the mountain farms, was that they all
had decayed teeth. In most cases all their front teeth had gone by the age
of thirteen or fourteen and their grinders (or molars) were just hollow
shells. What was the cause of this? When we moved on to study the teenagers,
tooth decay was the norm also. It happened that their teeth were literally
dissolving away. The gums were extremely healthy. Losing their teeth at a
comparatively early age means that they have to subsist on soft foods and
most of the people had a diet that is gruel-based. I asked the old people
how they managed to eat, and they indicated--often in most amusing ways and
with many mouth openings to show jaws bereft of teeth--that their gums had
become hardened. If the decay was to do with small traces of lead then the
gums would not have looked so healthy. The gums in fact would have looked as
they do in some forms of periodontal disease, soft and glue-like, and would
be bleeding constantly. None of these signs existed. And there is no doubt
that they could not have been so lucid at the end of their days if they had
had excessive lead in their diet. Even slightly too much affects the brain.
   If the gums do harden, so it seems do the muscles of the face, for the
people in these villages do not seem to lose the contours of their faces as
is so often found in the toothless in Europe. In fact, to have one's teeth
extracted is normally the quickest way to start looking old.

   Sugar we thought was not the culprit: there was very little of this in
their diet. True, as children they often suck sugar cane as a form of sweet,
and this was about the only thing they would ever get in this line; but it
would be unlikely to be the cause of such excessive tooth rot, especially
when there is plenty of information about the children in south-east Asia
who suck on this from the age of three to twenty-three with no obvious decay
in their teeth.

   One day when business was a little slack the priest, Padre Francisco
Bravo, came and said he had something rather interesting to show us in his
office, and there on his desk he had a freshly dug up human skull. It still
had earth and roots clinging to it. I examined this. It was that of a young
woman and from its sutures she could not have been beyond the age of
twenty-five. The few remaining teeth in the upper jaw were badly
decayed--not by periodontal disease, which is mostly caused by faulty
diet--but the teeth were decaying, the front ones nearly all gone and the
grinders just shells, as could only occur through the slow destruction of
some mineral. The skull was at least 300 years old. It had been found in an
old cemetery at the other end of the village and had been brought to the
padre for safe keeping. Now this and others that were brought in from the
cemetery indicate that conditions in the area in earlier days were similar
to those found now; whatever it was that caused the decay, the owner of the
skull must have had a difficult time trying to eat a normal diet, and must
have been eating food of a soft nature. It was not the skull of an Indian.

...

 The girl was beautiful. Her figure was shapely enough, but something we did
caused her to smile and there were almost no teeth there! All the front
teeth had gone and there were only the grinders left. I asked the men who
were with me about this and they said it was usual for people not to have
any teeth after the age of twenty--wasn't it the same in England? This
sounded interesting. We had a chance to check the mouths of the others; one
of the men with us had only one tooth in his entire mouth. The other man,
who turned out to be 120 years old, also had no teeth and had had none for
fifty years, and yet his face had not shrunk. This seemed to indicate
something special about their diet which could also be linked with
longevity; it could also be that, having to subsist on gruel from early in
life, some internal reaction was perhaps set up which gave their insides
little work to do and helped them to live to their great ages. But people
have studied so little about diet that it is still not known if the
consistency of a diet is of importance to health or not. It is known that a
diet that gives the intestines too much work can injure them--such as the
diet of our ancestors in the Middle Ages, who were thought to become
prematurely old partially through this. But what caused their teeth to go so
early in the first place? Was it the same cause which allowed them to remain
generally healthy--something harmful to the teeth but good for the body?
Sugar was not the culprit: there was very little of this in their diet. In
fact, the only thing obviously likely to cause decay that we immediately
came across was the locally made rum. We wondered whether a trace element in
the water could be affecting the teeth and maybe other areas of their
bodies. This we investigated later, and came to some interesting
conclusions, discussed in a later chapter.>


jean-claude