My friend Judy Siegel who is the pro-breastfeeding health correspondent of 
the Jerusalem Post sent me this.  This study shows a lot of stuff that we 
know but it is interesting that human milk is valuable to the human baby not 
just because of its nutritional and immunological benefits but in the way it 
affects the intestines for life: nurturing the good bacteria and eliminating 
the bad.
Bravo to these researchers because for sure they were not funded by any 
formula company, dairy board or even the American Peanut Board (see my 
previous posting)!!

Wendy Blumfield
Israel Childbirth Education Centre
NCT Trained Tutor ANT/BFC


Subject: NYTimes: Breast Milk Sugars Give Infants a Protective Coat


August 2, 2010
Breast Milk Sugars Give Infants a Protective Coat
By NICHOLAS WADE

A large part of human milk cannot be digested by babies and seems to
have a purpose quite different from infant nutrition — that of
influencing the composition of the bacteria in the infant’s gut.

The details of this three-way relationship between mother, child and
gut microbes are being worked out by three researchers at the
University of California, Davis — Bruce German, Carlito Lebrilla and
David Mills. They and colleagues have found that a particular strain
of bacterium, a subspecies of Bifidobacterium longum, possesses a
special suite of genes that enable it to thrive on the indigestible
component of milk.

This subspecies is commonly found in the feces of breast-fed infants.
It coats the lining of the infant’s intestine, protecting it from
noxious bacteria.

Infants presumably acquire the special strain of bifido from their
mothers, but strangely, it has not yet been detected in adults.
“We’re all wondering where it hides out,” Dr. Mills said.

The indigestible substance that favors the bifido bacterium is a slew
of complex sugars derived from lactose, the principal component of
milk. The complex sugars consist of a lactose molecule on to which
chains of other sugar units have been added. The human genome does
not contain the necessary genes to break down the complex sugars, but
the bifido subspecies does, the researchers say in a review of their
progress in today’s Proceedings of the National Academy of Sciences.

The complex sugars were long thought to have no biological
significance, even though they constitute up to 21 percent of milk.
Besides promoting growth of the bifido strain, they also serve as
decoys for noxious bacteria that might attack the infant’s
intestines. The sugars are very similar to those found on the surface
of human cells, and are constructed in the breast by the same
enzymes. Many toxic bacteria and viruses bind to human cells by
docking with the surface sugars. But they will bind to the complex
sugars in milk instead. “We think mothers have evolved to let this
stuff flush through the infant,” Dr. Mills said.

Dr. German sees milk as “an astonishing product of evolution,” one
which has been vigorously shaped by natural selection because it is
so critical to the survival of both mother and child. “Everything in
milk costs the mother — she is literally dissolving her own tissues
to make it,” he said. From the infant’s perspective, it is born into
a world full of hostile microbes, with an untrained immune system and
lacking the caustic stomach acid which in adults kills most bacteria.
Any element in milk that protects the infant will be heavily favored
by natural selection.

“We were astonished that milk had so much material that the infant
couldn’t digest,” Dr. German said. “Finding that it selectively
stimulates the growth of specific bacteria, which are in turn
protective of the infant, let us see the genius of the strategy —
mothers are recruiting another life-form to baby-sit their baby.”

Dr. German and his colleagues are trying to “deconstruct” milk, on
the theory that the fluid has been shaped by 200 million years of
mammalian evolution and holds a wealth of information about how best
to feed and defend the human body. Though milk itself is designed for
infants, its lessons may apply to adults.

The complex sugars, for instance, are evidently a way of influencing
the gut microflora, so they might in principle be used to help
premature babies, or those born by caesarean, who do not immediately
acquire the bifido strain. It has long been thought there was no
source of the sugars other than human milk, but they have recently
been detected in whey, a waste byproduct of cheesemaking. The three
researchers plan to test the complex sugars for benefit in premature
infants and in the elderly.

The proteins in milk also have special roles. One, called Alpha-
lactalbumin, can attack tumor cells and those infected by viruses by
restoring their lost ability to commit cell suicide. The protein,
which accumulates when an infant is weaned, is also the signal for
the breast to remodel itself back to normal state.

Such findings have made the three researchers keenly aware that every
component of milk probably has a special role. “It’s all there for a
purpose, though we’re still figuring out what that purpose is,” Dr.
Mills said. “So for God’s sake, please breast-feed.”

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