Page 8 - November Rolling Stone

Page 8
November, 2016
Digestion
Digestion starts with the sight, thought, or smell of food. When the brain anticipates an incoming meal, the vagus nerve sends a message to the stomach causing the release of acetylcholine. The binding of acetylcholine to G cells in the stomach starts the secretion of gastrin and, in combination with acetylcholine and histamine, stimulates parietal cells in the gastric glands of the stomach body to start secreting hydrochloric acid (HCl).
WHEW! That was complicated! I just wanted you to see how involved digestion really is. For the purposes of this article, we will focus on hydrochloric acid found in the stomach.
Hydrochloric acid is a strong acid, produced by the lining of the stomach, that breaks down connective tissue
and cell membranes in the food, so that it can more easily be acted on by digestive enzymes. Hydrochloric acid also kills most of the bacteria ingested with the food.
HCl is a NORMAL constituent of gastric juice in humans and other animals. Low hydrochloric acid in the stomach, called hypochlorhydria, may be found with chronic gastritis as well as other chronic illnesses.
Acid in the stomach serves several purposes but is mostly associated with breaking down proteins and polysaccharides so they can cross the intestinal epithelium. Approximately 2 L of HCl is produced daily.
The normal increase in HCl, the distention against the lining of the stomach caused by the presence of food, and decreasing pH level, cause the partially digested bolus of food to move along the digestive tract. Hydrochloric acid helps kill bacteria normally ingested with food. Long term depletion of HCl can cause some dangerous bacteria to enter through the intestine and lead to serious health
Cont. on page 9, Digestion