Effect of L-Lactic Acid on the Absorption of Calcium in Gastrectomized Rats.

Abstract

SummaryThe effect of dietary L-lactic acid (LA) (0.5, 10, or 2.5g/100g of diet) on the absorption of calcium in gastrectomized rats was evaluated for 28d. Calcium phosphate was used as a source of calcium. The apparent calcium absorption ratio and the calcium contents of the femur and tibia in gastrectomized rats fed the control diet were significantly less than those in sham-operated rats. In the gastrectomized rats, the apparent calcium absorption ratio and the calcium contents of bone in the rats fed the lower doses of LA diets (LA 0.5 or 1.0g/100g of diet) were not affected; however, the apparent calcium absorption ratio and the calcium contents of bone in the rats fed the highest doses of LA diet (LA 2.5g/100g of diet) were greater than those in gastrectomized rats fed the control diet. Dietary LA (2.5g/100g of diet) also enhanced the phosphorus absorption and bone phosphorus content in the gastrectomized rats. We speculated that the highest dose of dietary LA might be associated with the dissolving of a water-insoluble form of calcium salt in the diet, thereby facilitating the calcium absorption and resulting in increased bone calcium content in gastrectomized rats.

Adverse Effects of Long-Term Proton Pump Inhibitor Therapy

“…Calcium carbonate disintegration and dissolution are pH-dependent and impaired by alkaline environments, decreasing from 96% at pH 1 to 23% at pH 6.1 [48]. Animal studies have shown that gastrectomy or PPI use and the resulting alkalization of the gastric environment may impair calcium absorption and bone density [49,50]. Restoring gastric pH by providing lactate has been shown to reverse calcium malabsorption in both cases [49,50].…”

Causes of Emergency Department Visits Following Thyroid and Parathyroid Surgery

“…13 Improvement in calcium absorption has been demonstrated in an gastrectomized animal model with administration of dietary lactic acid. 11 Unfortunately, in human studies, there have been conflicting results with regard to calcium absorption in the setting of altered gastric pH and PPI use. [13][14][15] This altered pH environment could also contribute to postoperative ED evaluations owing to altered medication absorption/clearance and changes in the gastric mucosal barrier.…”

“…8 Changes in gastric acid secretion affects the absorption of many nutrients and vitamins owing to the manipulation of the normally low pH environment. [10][11][12][13] It is assumed that long-term PPI use leads to decreased intestinal absorption of calcium owing to lower solubility of calcium salts in the higher gastric pH environment. 13 Improvement in calcium absorption has been demonstrated in an gastrectomized animal model with administration of dietary lactic acid.…”

Long-term Proton Pump Inhibitor Therapy and Risk of Hip Fracture

“…29 In rats, gastrectomy or omeprazole therapy leads to malabsorption of calcium phosphate and impaired bone mineral density. 11,30 Lowering gastrointestinal pH with dietary lactate reversed the calcium malabsorption in both cases. 11,30 In humans, both gastrectomy and pernicious anemia are associated with increased risk of osteopenia and fracture, 31,32 although it is unclear whether achlorhydria is the primary culprit.…”