Lactose calcium absorption

Other selective forces may also have been at work. Flatz (1987) has suggested that calcium absorption was a factor in northern Europe. Lactose is known to facilitate calcium absorption in the intestine. The northerly climate frequently prevented skin exposure to sunlight, thereby reducing the body s production of vitamin D. With little vitamin D available, calcium was poorly absorbed and conditions such as rickets could result. The ability to digest lactose would not only allow adults to use an excellent source of calcium, but the lactose would also facilitate its absorption. 

Milk is one of the best dietary sources of calcium, not only because of the significant quantity of the mineral present but also because of (1) its calcium-to-phosphorus ratio (1.3 1), which is conducive to optimal skeletal growth, and (2) the presence of nutrients such as lactose and vitamin D in vitamin D-fortified milk, which promote calcium absorption (Ziegler and Fomon 1983 Schaafsma 1983 Renner 1983). 

Kocian, J., Skala, I, and Bakos, K. 1973. Calcium absorption from milk and lactose-free milk in healthy subjects and patients with lactose intolerance. Digestion 9, 317— 324. 

A variety of dietary sugars may eirhance the rate of calcium absorption, though the mechanism of this effect remains unclear (Schuettc et af., 1989). This effect has brought attention to the sugar in milk (lactose) as a nutrient that can enhance calcium absorption. This effect of lactose is not unique other sugars can produce the Same effect. 

Schuette, S. a., RnowTes,. and ford, H- E. (1989). Effect of lactose or its component sugars On jejunal calcium absorption in adult man. Am. ]. CJirt. Nuir. 50,1084-1087. 

Intestinal calcium absorption is influenced by dietary factors. Lactose and other sugars increase water absorption, thereby enhancing passive calcium uptake. The effect of lactose is especially valuable because of its presence in milk, a major source of calcium. Lactose also increases absorption of other metal ions. This effect may contribute to the incidence of lead poisoning (plumbism) among young inner-city children exposed to high dietary levels of both lead and lactose. 

Administration. Most children and adults do not ingest sufficient dietary calcium and require supplements (see Tables 88-5 and 88-6). Individuals with certain characteristics or conditions—such as lactose intolerance nondairy vegetarian diet malnutrition low-fat diets and glucocorticoid, antiresorptive, or parathyroid therapy—also require evaluation for calcium supplementation. To ensure adequate calcium absorption, 25(OH) vitamin D concentrations should be maintained in the normal range." ... 

There are many scientific evidences, supported by clinical studies, on the efficacy of probiotics in the prevention and treatment of gastrointestinal disorders, respiratory, and urogenital diseases. Many microbial strains with probiotic properties are able not only to restore the intestinal microbial balance, but also to impart other beneficial effects on health, associated with the production of acids, bacteriocins and with the competition with pathogenic microorganisms. Among these, the main effects are the reduction of the level of cholesterol in the blood, the reduction of fecal enzymes, with potentially mutagenic activity that can induce the onset of tumors, the reduction of lactose intolerance, the increase of the response of the immune system, the increase of calcium absorption, and synthesis of vitamins. ... 

Gallagher et al. (1974) studied the effect of fermented dairy products (buttermilk, yogurt, and cottage cheese) on lactose tolerance and calcium absorption in three lactase-deficient subjects. Three diets (fermented dairy products, completely lactose-free diet, and nonfermented dairy products) were served in sequence for 4 d each. The three lactase-deficient patients tolerated the fermented dairy products without symptoms of lactose intolerance, whereas consumption of nonfermented dairy products... 

Cochet, B., Jung, A., Griessen, M., Bartholdi, P., Schaller, P., and Donath, A., 1983, Effect of lactose on intestinal calcium absorption in normal and lactase-deHcient subjects. Gastroenterology 84 935. 

Lactose. Dietary lactose (milk sugar) enhances the rate of calcium absorption from the small intestine. In this connection, it is noteworthy that (1) milk is the only source of lactose, and (2) the improved absorption of calcium is dependent on the activity of intestinal lactase, the enzyme that hydrolyzes lactose. 

Lactose improves calcium absorption in young infants, in whom absorption of calcium is predominantly by passive transport. In adults, the presence of lactose in the diet has little effect on the efficiency of calcium absorption. 

Lactose appears to promote the absorption of calcium but this is probably due to a nonspecific increase in intestinal osmotic pressure, an effect common to many sugars and other carbohydrates, rather than a specific effect of lactose. 

Lactose appears to stimulate the intestinal absorption and retention of calcium. The effect may not be due to lactose but rather to its metabolic product, lactic acid, formed by microbial action in the gut. The... 

Kobayashi, A., Kawai, S., Ohbe, Y. and Nagashima, Y. 1975. Effects of dietary lactose and a lactase preparation on the intestinal absorption of calcium and magnesium in normal infants. Am J. Clin. Nutr. 28, 681-683. 

The fourth section deals with various aspects Digestion, Absorption, and Nutritional Biochemistry. The chapter Obesity considers current problems with respect to the ever-increasing incidence of imbalance between energy intake and utilization. Key problems of undemutrition are discussed in the chapters Protein-Energy Malnutrition and Vitamin A Deficiency in Children. The chapters Lactose Intolerance, Pancreatic Insufficiency, and Abetalipoproteinemia focus on the biochemical processes underlying food digestion and absorption. Calcium Deficiency Rickets, Vitamin B12 Deficiency, and Hemochromatosis provide discussions of absorption and utilization of vitamin D, vitamin B12, and iron, respectively. 

About 99% of the calcium ions in the body are in bones and teeth. Together with sodium and potassium ions, calcium ions also participate in transmission of nerve impulses and regulation of the heartbeat. To be absorbed, calcium must be present in solution as Ca. Absorption is enhanced in the presence of lactose (milk sugar) and also by a fatty meal, which passes through the intestine more slowly, allowing more time for absorption. A deficiency of vitamin D decreases calcium ion absorption and contributes to the bone deformities that accompany rickets. 

The choice of a diluent may influence the absorption of an active substance, which was seen in the l%Os in Australia. The diluent of phenytoin sodium capsules was changed from calcium sulfate dihydrate to lactose, which strongly enhanced the bioavailabdity of phenytoin sodium. Plasma levels of phenytoin increased up to fourfold, which led to an increased reporting of adverse events [8,9]. This case drew worldwide attention and resulted in an increased awareness of the importance of pharmaceutical availability and bioavailability of active substances in the development of solid oral dosage forms. 

Calcium is the most abundant essential mineral in the human body, 99% being located in the bones and teeth. Caldum salts have been used therapeutically in many conditions, such as lactose intolerance, osteoporosis, premenstrual syndrome, colorectal cancer, kidney stones, and multiple sclerosis. Calcium supplementation has long been regarded as a fimdamental part of the prevention and treatment of postmenopausal bone loss. Several other health benefits have also been suggested, including improvements in blood pressure and serum cholesterol. Its adverse effects include constipation, bloating, and gas [Ifi ], as well as interference with the absorption of phosphate [17. ... 

The carbohydrate present in milk is lactose, a compound sugar synthesized only in the mammary glands which promotes the absorption of calcium from the ileum. 

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