Saturday, 6 September 2014

Another penny drops: Why severe hyperinsulinamia can occur with a small increase in exogenous carbohydrate intake.

This blog post is a result of Vim's comments in the previous blog post. A penny suddenly dropped!
From http://bja.oxfordjournals.org/content/85/1/69.full

Insulin has a Chalonic (inhibitory) action on blood glucose level (via the liver, muscle mass & fat mass), blood FFA level (via fat mass) and blood ketone body level (via the liver).

As mentioned in the comments, GHB has a stimulant effect - up to a certain level of blood GHB. Beyond that level, there's a powerful sedative effect. This is because at low levels of exogenous ketone body input, insulin secretion increases slightly to reduce hepatic ketogenesis.

At a certain level of exogenous ketone body input, hepatic ketogenesis falls to zero and cannot be reduced any further. Any slight increase beyond this point in exogenous ketone body input, results in a large increase in insulin secretion, as the pancreas increases Ketone body-Stimulated Insulin Secretion to maximum in a (failed) attempt to reduce blood ketone body level.

Exactly the same thing happens with exogenous carbohydrate or BHB input.

At a certain level of exogenous carbohydrate input, hepatic glucogenesis falls to zero and cannot be reduced any further. Any slight increase beyond this point in exogenous carbohydrate input, results in a large increase in insulin secretion, as the pancreas increases Glucose-Stimulated Insulin Secretion to maximum in a (failed) attempt to reduce blood glucose level.

7 comments:

Vim said...

Thanks once more form all your effort Nigel.

Vim said...

BTW
http://eatingacademy.com/personal/experience-exogenous-ketones

Nigel Kinbrum said...

If you hadn't asked the questions you asked, I wouldn't have thought about what I thought about , so thank you for stimulating my brain. This is why I welcome comments.

Vim said...

It`s raining pennies today:

Indeed, there was a concomitant fall in FFA and in glycerol levels
averaging respectively 13.5% and 17.3%, without significant changes in
peripheral insulin concentrations.

http://www.metabolismjournal.com/article/0026-0495%2875%2990092-X/abstract


Well, I'll keep squeezing my head on that this week-end.

Nigel Kinbrum said...

There's more than one loop controlling blood ketone level, involving direct inhibition of hepatic ketogenesis, in addition to the insulin NFB loop.

The blood glucose NFB loop involves 3 different target tissues (liver, muscle mass & fat mass) and several hormones (insulin, glucagon, adrenaline, cortisol & GH).

I'm guessing that multiple loops results in a more robust system.

However, whack enough exogenous "X" in, and any loop will eventually hit an end stop!

weilasmith said...

"Any SLIGHT INCREASE beyond this point in exogenous carbohydrate input, results in a large increase in insulin secretion..." how many grams of carbohydrate is a slight increase? how would an individual figure that? since i seem to have diminished phase 1 insulin response (bg got to 165 at half hour on OGTT), would i just monitor my bg with a glucose meter and when it got to X number at i hour, i would know that that was my limit before my body started producing lots of insulin?

Nigel Kinbrum said...

Basically, you just have to "suck it and see". You go from feeling great to feeling really sleepy when you exceed your limit.