Digestion starts in mouth? Insulin?

Question

I heard digestion starts in mouth as food is being chewed.

So saliva digests portion of carbs in mouth, and food is broken

down into smaller peices in mouth, I get that. But, I also read

that chewing has furthur effect of releasing insulin in anticipation

of food intake.

My question is...

What part of digestion in mouth cause insulin release?

Is it responding to the carbohydrates detected in mouth ?

Is it responding to mechanical movement of the jaw?

Is it responding to sight of food or the taste?

or what??

Answer 1

Maltase is the enzyme in saliva that begins the digestive process. It begins to digest the food into simpler sugars and makes it easier for other digestive enzymes to work once the food encounters the stomach and gut.

The absorption of simple sugars into the bloodstream through the oral mucosa (surfaces of the tongue, cheeks, f

and floor of the mouth) will trigger the release of insulin in very small amounts. The majority of the insulin isn't released until the food is partially digested by the stomach and enters the small intestine, where the sugars enter the bloodsteam. The body responds by releasing enough insulin into the bloodstream to cover the concentration of sugars and their metabolism.

Answer 2

Insulin is secreted at the smell, sight and expectation of food.

This is known as the cephalic phase of insulin

secretion and is due hypothalamo-entero-insular

axis which is mediated by vagal nerve. During

feeding the parasympathetic nerves are activated

and are instrumental for the cephalic phase of

insulin release.