OH! Magazine - Australian Version June 2015 | Page 15

DR
JOANNA

PROTEIN INTAKE

www.drjoanna.com.au

( Nutrition )

AND BABIES

Dr Joanna explores the role of protein for babies.

ecently I chaired some sessions
at a symposium on protein in
paediatrics in Melbourne (VIC). It was an
absolutely fascinating scientific meeting
and it’s really rare to come away from
these events with such a clear message
that has the potential to make a huge
difference. That is indeed the case for
this event.

R

The take-home message was that a high
protein intake in infancy increases the
risk of overweight and obesity in the child
at school age and beyond.
This might sound surprising to you, since
protein has long been the darling
macronutrient that seemingly can’t put a
foot wrong.
We have shifted the finger of blame from
fat to carbohydrate, while protein has
been elevated to star status. Protein fills
us up, helps us to feel satiated, reduces
the hunger pangs between meals so that
we eat less, and ultimately helps us to
lose body fat and gain muscle. For adults,
a high protein diet has been shown to be
beneficial in this regard, but not for
babies or young kids.

The story starts with observational studies
that noted that babies and toddlers to
two years of age with rapid weight gain
had an increased risk of obesity later in
life.
Furthermore, those babies who were
breastfed – and the longer the better –
were far less likely to have such rapid
weight gain and consequently have a
lower risk of being overweight or obese
years later; and we’re not talking small
number here. The magnitude is in the
range of a 15 to 25 per cent lower rate of
obesity in breastfed kids.
The question, therefore, is what is it that
is protective about breastfeeding? Or
conversely what is it about bottle-feeding
with infant formula that promotes the
increases in weight gain?

It’s a lesson in life-cycle nutrition, where
we have different nutritional needs at
various stages of life, and applying our
adult dietary approaches to our children
is potentially hazardous – and this is just
one example.

One of the differences between the two
forms of milk is the protein content.
Human milk is an amazingly complex mix
of proteins involved not just in growth,
but those that have roles in immunity,
digestion and in promoting a healthy gut.

One of the senior researchers in this area
is Professor Berthold Koletzko from
Munich University in Germany. He was a
guest speaker at the symposium and it is
his research that is central to the
conclusions drawn.

In short, the quality and quantity of
proteins is very different to those found
in formula. To try to replicate the quality
of protein, particularly with respect to the
amino acid profile, infant formulas have a
far higher quantity of protein present.

This is even more marked for babies 6 to
12 months of age. The protein content of
human breast milk declines over the first
year. (I find it fascinating that compared
to the milk of other mammals, human
milk is far higher in carbohydrate and
lower in protein reflecting the human
infant’s different nutritional needs).
Conversely, follow on formulas designed
for 6 to 12 month old infants tends
towards a higher protein content that the
starter formulas. The result is that
formula-fed infants consume about twice
the protein as breastfed infants.
This observation lead researchers to
hypothesize that it is this considerably
higher protein intake that is driving the
rapid weight gain in formula-fed infants.
So Professor Koletzko and his team,
along with several other European
countries in the European Childhood
Obesity Project, set out to test the
hypothesis. They compared three groups
of infants. The reference group was
infants breastfed for at least three
months. Those who were being formulafed were then randomised to receive
either the conventional higher protein
formula, or an intervention formula with a
lower protein content closer to that found
in breast milk (although still slightly
higher).

( OH! MAGAZINE ) JUNE 2015

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