I am not a nutritionist, but something like that has not stopped me from
offering an opinion before.

In the first place, if the baby is growing steadily, and is in good
health otherwise, there is no need for him to be higher than the 5th
percentile.  The only measurement of the three mentioned which is easy
to do and relatively accurate is the weight.  If any of you out there
have ever tried to measure the length or head circumference of a one
year old, you know what I mean.

Let us for the moment though, assume that it would be good for the baby
to get more fat.  There are zillions (slight exaggeration) of ways to
get him more fat.  Add olive oil, or other oil to his food (mashed
potato with olive oil--yummee).  Avocado is a good source of fat.  In
theory, butter, being only fat, should not contain any milk protein, but
you can't count on that.  If the parents are not vegetarians, there is
plenty of fat in things such as salmon (especially Atlantic-get it quick
while you still can) and some meats.

As Gay Palmer wrote in the Politics of Breastfeeding, the push to give
milk and make it a wonder food comes from the fact that England had an
abundance of milk.  If avocados grew in England, they would have pushed
that on their hapless colonies.

Jack Newman, MD, FRCPC