The suggestion that cultural pressures exert a change on our diet, and may
explain unhealthy eating patterns, at a certain level this seems
unsatisfactory.  There is almost indisputably some influence from culture
(for example, most Americans have a strong aversion to eating insects,
which are popular in many other cultures).  But can this be the primary
explanation for bad eating patterns?

Certainly, if homo sapiens has any innate instinctive or biochemical drive
toward eating a certain way, then we would probably expect to see that most
cultures would drive the most powerful members of a society to eat the most
healthy foods.  Apparently such a drive does not exist, or if it does it's
easily overridden.

On the other hand, the idea that any animal species knows "instinctively"
how to eat right strikes me as questionable.  I have seen many domesticated
animals who are quite fat and sluggish.  Relatives of mine have a dog, it's
a small dog that should weigh no more than 15-20 pounds but weighs easily
twice this and can barely manage to navigate stairs.  I see no reason to
think that other species really have an instinct to perfectly eat exactly
the right things whenever possible and to never eat "wrong."

Human beings, in my experience, eat foods which taste good to them.  Do we
have to be taught to be attracted to highly sweet or very rich foods?   Did
we as children need to be "taught" to like candy?  Why does every culture
on the planet seem to snap up foods common to the western world, such as
candies, white breads, etc. as saon as it's available to them?  Is it
because some psychological factor has them wanting to emulate us?  Or is it
possible that sweet, fatty, calorie-dense, easy-to-obtain, easy-to-prepare
foods in general are pleasing to most any animal?

If bad eating habits are entirely socially derived, then we would also
expect that changing social attitudes would show effective improvements in
health, yes?