oxytocin (was Re: Milk was another weird fasting poop

[Guest guest]

And what about this? Oxytocin - the hormone that creates bonding

between mother and child - is also present in her milk.

JC

Mothering and Oxytocin

or

Hormonal Cocktails for Two

by Blaffer Hrdy and C. Sue

from © Natural History, 12/95

When first presented with pups, a virgin female laboratory rat

generally ignores them; she may appear afraid of the tiny, squirming,

naked creatures and, occasionally, may even eat them. Only after

being introduced to pups many times over several days can a virgin

rat be conditioned to tolerate and care for them licking them,

crouching protectively over them, retrieving them when they stray

from her side. In contrast, a pregnant rat responds within minutes to

pups, even prior to delivery of her own.

The idea that physiological changes might prepare the expectant

mother for her new role led to a now classic experiment. In 1968

ph Terkel and Jay Rosenblatt, of Rutgers University, injected

blood from a rat that had just given birth into a virgin female. The

result was a dramatic reduction in the time it took virgins to

nurture pups.

Since 1968, we have learned a great deal about what goes on inside

female mammals as they prepare for motherhood. During the last third

of pregnancy, a cascade of endocrinological events readies and

motivates mothers. Prominent in this maternal cocktail are the

steroid hormones estrogen and progesterone, manufactured by the

placenta and essential to maintaining pregnancy. But since the

placenta is delivered along with the baby, progesterone and, a little

later, estrogen levels fall around the time of birth. By themselves,

these hormones cannot account for maternal responsiveness.

Enter prolactin and oxytocin, hormones essential for milk production

and nursing. Prolactin is a very ancient molecule whose original

function was to maintain salt and water balance in early vertebrates

such as fish. Over evolutionary time, this hormone has proved very

versatile and now performs diverse physiological functions in many

kinds of animals. In mammals, it is associated with caretaking

behavior in both females and males.

But perhaps the quintessential mammal hormone is oxytocin. A muscle

contractor, oxytocin (from the Greek for " swift birth " ) evolved in

mammals and produces the uterine contractions of birth and milk

ejection during lactation. Present when the mother first greets her

emerging offspring, it continues to be released whenever she nurses.

Oxytocin released into the brain is known to promote calming and

positive social behaviors, such as pair bonding. Studies of domestic

sheep by Barry Keverne, Kendrick, and their colleagues at the

University of Cambridge provide the most complete picture we have of

the behavioral effects of oxytocin. As a lamb moves down the birth

canal, nerves stimulated during the passage trigger the release of

oxytocin in the mother's nervous system. Only if oxytocin is present

at birth or injected so that it reaches the brain at the same time a

mother meets her newborn, will she bond with her offspring. If

release of oxytocin is blocked, the ewe rejects her lamb. High levels

of oxytocin also are found in mother's milk, raising the possibility

that this hormone plays a role in making the mother infant attachment

mutual.

As important as these hormones can be in determining how responsive a

mother will be, they do not act in a deterministic fashion. They both

affect and are affected by a mother's behavior and her experience.

Exposure to pups, for instance, can lead to reorganization of neural

pathways in a mother rat's brain, making her respond faster to pups

in the future, even with lower hormone levels. And some recent

studies suggest that the hormones of breast-feeding may benefit a

mother's mental health and increase her ability to deal with stress.

In many mammals, males, as well as adoptive virgin females, can be

primed to exhibit parental behaviors. Prairie vole males, for

instance, typically respond to a newborn pup by retrieving it and

huddling over it. Geert De Vries, of the University of Massachusetts,

found that such nurturing is facilitated by vasopressin, a hormone

that in other contexts is associated with aggressive, territorial

behavior.

www.people.virginia.edu

> > First, in my view, WAPF is too accommodating when it comes to

refined and

> > dense carbs, including sugars. Rapadura and maple syrup are

promoted as if

> > they're meaningfully better than table sugar when in fact the

differences

> > are small.

>

> Agreed. BUT....I think this is in part due to the fact that WAP/NT

way

> of thinking and eating requires a huge about face for most folks.

The

> dietary philosophy of the foundation is in direct opposition to most

> of the information we get from newspapers, doctors, etc. In fact,

my

> mil just said to me yesterday: " I don't care what you say, saturated

> fat is bad for you--everybody says so. " I think the transition

period

> is important and that in order for people to successfully convert

to a

> better diet, they might need to use maple syrup for awhile while

they

> wean themselves off of a corn syrup diet. I certainly did that. I

> don't use sweeteners much at all now, unless I'm making dessert for

> dinner guests.

>

> > Also, grains are promoted as healthy foods, at least when

> > prepared properly, but AFAIK " properly " is a lot more strict

than NT and WT

> > generally let on. (Have you looked at the recipes in _Eat Fat,

Lose

> > Fat_? Lots of plain old flour there. And IIRC, Sally Fallon

has said that

> > even true sourdough is a " compromise " food.)

>

> Also agreed. They need to address this issue for sure. Haven't

read

> EFLF but I'll take your word for it.

>

> >

> > Eating the right foods is a big deal. I don't want to

understate it. But

> > organic and grass-fed and high-fat aren't enough. The number of

farms with

> > _really_ good soil is probably minuscule, and unfortunately,

those of us in

> > the northeast are particularly screwed -- and until a couple

months ago,

> > you were here in the northeast.

>

> True. I guess I just do my best and try not to worry about it too

> much. Naive, perhaps, but allows me to function.

>

> > I know someone

> > who just had a mildly underweight, mildly premature baby.

(6#2oz, 2-3

> > weeks premature, IIRC.) A friend of hers gave her a LLL book

and urged her

> > to breastfeed. I don't actually know whether she intends to use

formula or

> > to breastfeed (or some combination, or what, and for how long)

but she has

> > no interest whatsoever in reading the book, and as she is

interested in

> > keeping up with her career, I'd say the odds are poor. But even

if she

> > nurses her baby, her milk is bound to be awful because her diet

sucks

> > rotten roadkill ass.

>

> Will her breastmilk suck worse than Enfamil? I highly doubt it.

>

> > That's a very good point, but IIRC, raw liver is part of that

recipe.

>

> There are two formula recipes in NT. One is milk based and has no

> liver and the other is broth and cooked liver based. Personally,

I'm

> not sure if a baby would take the liver based recipe. I'll bet most

> folks would try the milk formula first, if only due to ick factor.

>

> > >Mike , perhaps...

> >

> > Doubtful. He believes in calorie restriction and avoiding too

much

> > nutrition. (That latter part sounds absurd, but I think it's a

fair

> > characterization of what he's said.)

>

> I was thinking of his grub-eating days...

>

>