Gastric acid
The main constituent of gastric acid is hydrochloric acid which is produced by parietal cells (also called oxyntic cells) in the gastric glands in the stomach. Its secretion is a complex and relatively energetically expensive process. Parietal cells contain an extensive secretory network (called canaliculi) from which the hydrochloric acid is secreted into the lumen of the stomach. The pH of gastric acid is 1.5 to 3.5 in the human stomach lumen, the acidity being maintained by the proton pump H/K ATPase. The parietal cell releases bicarbonate into the bloodstream in the process, which causes a temporary rise of pH in the blood, known as an alkaline tide.
Alkaline diet
Alkaline diet (also known as the alkaline ash diet, alkaline acid diet, acid ash diet, and acid alkaline diet) describes a group of loosely related diets based on the misconception that different types of food can have an effect on the pH balance of the body. It originated from the acid ash hypothesis, which primarily related to osteoporosis research. Proponents of the diet believe that certain foods can affect the acidity (pH) of the body and that the change in pH can therefore be used to treat or prevent disease. Due to the lack of credible evidence supporting the claimed mechanism of this diet, it is not recommended by dietitians or other health professionals, though some have noted that eating unprocessed foods as this diet recommends may have incidental health benefits unrelated to bodily pH.