Someone posted:
>The biggest problems we would have at WIC would be with breastfeeding babies
>of Asian parents, whose parents were tiny themselves (and frequently very
>anxious about BFing as well). We would frequently be on the phone to docs
>who didn't seem to have noticed that this baby who's in the fifth percentile
>belongs to a mother who's  85 pounds and 4' 9" tall herself.

Asian populations are NOT genetically small and tiny.  They have the normal
range of human variation in size that any population has, but on average --
when they have access to adequate nutrition and good health, they grow like
average Americans.  It may take several generations to overcome the results
of many generations of poor nutrition and lots of diseases and emotional
turmoil in childhood, but these can be overcome, as they are environmental
in origin, not genetic.

The average height for "white" US men is currently 5'9" and the average
height for men of Asian-American descent whose families have been in this
country for several generations is 5'8".

It is a common, but erroneous belief, that Asians (especially southeast
Asians such as the Vietnamese) and Latin Americans (especially Mexicans and
Mayans from Guatemala) are genetically short.  They are not genetically
short.  They are short from generations of poor nutriiton, lots of disease,
and emotional turmoil during childhood (from civil war and international war).

If I had an Asian mother who weighed 85 pounds and was 4'9" tall, I would
want to know -- where she was from, where she was born, the conditions she
lived under when she was a child, when she came to the US, and the heights
of other people in her family.

If she was fourth generation American and everyone in her family was very
short even though they were upper class, then I would expect her baby to be
small also.

If she was born and raised in Vietnam til 12, then spent 10 years living in
refugee camps, and came to the US in 1996 as an adult, and her younger
siblings who came to the US are all much taller than she is -- then I would
expect her baby to grow more like the American standards, and NOT as though
the baby was genetically small.  As I said, it takes more than one
generation of good food and health to overcome many generations of poor
environmental conditions.  But I certainly would not expect the US-born baby
of immigrants to grow like the immigrants did back home.

This trend, for populations to achieve more and more of their genetic
potential over time as conditions improve, is known as "positive secular
trend" and can easily be seen by going to any US mall and watching the
non-European families as they shop.  Here in Texas it is most commonly
Hispanic families that one sees -- where grandma is 4'9" tall (born and
raised in Mexico, came to Texas as an older adult), mother is 5'2" tall
(born in Mexico, came to US as a child), and daughter is 5'6" tall at 12
years of age (born and raised in the US).

In other parts of the country, you can see it with the stair-step
generations of Asian-Americans, or Guatemalan-Americans, etc.

Don't think that just because someone's parents are short that the baby
*should* be short as well.

Consequences of inadequate food and lots of disease and emotional stress in
childhood, in addition to short height and low weight, are: lower cognitive
scores, lower school performance, lower capacity for endurance labor, poorer
reproductive success (more miscarriages, stillbirths, deaths of young
children), and more diseases in adulthood.

Katherine A. Dettwyler, Ph.D.
Associate Professor of Anthropology
Texas A&M University

P.S.  African pygmies are the exception to the above.  *Most* of their
height deficit is due to a genetic deficiency of insulin-like growth factor
number one.

P.P.S.  Can't resist a plug for Texas A&M's star defensive back, Day Nyugen,
born the last of many children in a family of VietNamese immigrants.  He was
born in a refugee camp in Arkansas.  He is 5'11" tall, weighs 195 pounds, is
a graduate student in agricultural economics here at A&M, by all accounts an
extremely nice young man and won all sorts of awards for his tackling
ability.  He is the tallest of all his siblings, and he has said you can
tell easily the birth order of the children, as though born first, in
VietNam, are the shortest, and they get taller and taller the younger they
were when they came to the US.

End of lecture for today.