On Sun, 5 Sep 1999, Ben Balzer wrote:

> It's actually said to be a vicious circle:
> High carbohydrate intake/ lack of exercise causes high insulin levels which
> eventually leads to "down-regulation" of insulin receptors, or insulin
> resistance.

This is the part that I don't quite understand.  I see that the
dietary carbohydrates (and protein, for that matter) cause the
blood sugar to rise, which triggers the release of insulin to
push it back down, by storing the sugars.  I see that this should
cause a *transient* rise in insulin levels, but I don't see why
this in itself should cause down-regulation of insulin receptors.

I also see that exercise should help to normalize blood sugars by
increasing them demand for them.

> The blood sugars then go up. The body then needs to use secrete
> more insulin to push the sugar down. Then there is more down-regulation, ie
> more resistance.

It's the down-regulation of the receptors that I don't
understand.  I can see how the saturated fats might contribute to
this, by changing the cell membrane characteristics, but I don't
quite see how the insulin itself would do it.

> You can see that hyperinsulinaemia is an early stage in the diabetic
> spectrum.

Yes.

> There is another explanation from the study of paleo diet and food-plant
> toxins (which primarily exist in grains):
> Protease inhibitors and lectins seem to have a specific adverse effect on
> the pancreas and pancreatic enzymes (as well as some effects on other organs
> and enzymes). The pancreas is the master controller of most of the endocrine
> system, particularly that relating to food and metabolism. One could
> hypothesise that the toxic proteins of the Neolithic diet are the main cause
> of the above vicious circle, more so than the high levels of carbohydrate in
> Neolithic food. One would also wonder if the Neolithic toxins actually kill
> off the insulin producing cells in the pancreas.

I don't quite see this, but I am interested to learn more about
how the protease inhibitors and lectins affect pancreatic
function.  To be responsible for insulin resistance they would
also have to contribute to the down-regulation of the insulin
receptors.  Is there evidence that this is in fact the case?

> If that were so, the  Paleolithic diet would be very effective for diabetics
> (but dangerous if they're on medication as their blood sugars might crash).
> In Neanderthin, Ray indicates that paleodiet has cured his diabetes and
> listmembers have indicated that they have had good results, ie their
> experience supports these ideas. Ray also believes that Neolithic toxins
> cause obesity, and I completely agree.

Does Ray claim that his diabetes has been cured in the sense that
he now has normal pancreatic function?  I haven't seen him claim
this, but I certainly may have missed it.

As for neolithic toxins being the cause of obesity, I regard it
as an interesting hypothesis but I can't say that I am aware of
much evidence to support it.  If there is specific support for
the claims that lectins, etc. down-regulate insulin receptors,
that would be a reasonably strong kind of support.  This is why I
am interested in learning more about this.

Thanks.

Todd Moody
[log in to unmask]