Nutrition lactose intolerance

However, lactose has two major nutritionally undesirable consequences - lactose intolerance and galactosaemia. Lactose intolerance is caused by an insufficiency of intestinal /S-galactosidase - lactose is not completely... 

American Academy of Pediatrics, Committee on Nutrition. 1978A. The practical significance of lactose intolerance in children. Pediatrics 62, 240-245. 

Torun, B., Solomons, N. W. and Viteri, F. E. 1979. Lactose malabsorption and lactose intolerance Implications for general milk consumption. Archivos Latinoameri-canos de Nutrition 29, 445-494. 

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. 

A variety of membrane-bound proteins are of vital interest to the medical and nutritional ientist, because defects or changes in these proteins can cause such problems as lactose intolerance, cardiovascular disease, cystic fibrosis, and diabetes. Sucrase-isomaltase, an enzyme of the small intestine, is a membrane-bound protein, bound to the plasma membrane of the cnterocyte (gut cell). Part of the production of this enzyme is depicted in Figure 1,26. in Step 1, the polypeptide chain is polymerized on the ribosome (shown in black). In Step 2, part of the amino add chain near the N terminus crosses the membrane of the ER into the lumen but some of the amino acids at the N terminus remain outside. Step 3 shows the protein assuming a three-dimensional shape within the lumen both the C and N... 

One management tactic suggested for such patients is the avoidance of dairy products. However, as milk is a major component in the human diet, this deprives them from the use of a valuable nutritional source. In addition, since milk can provide much of the required calcium for maintaining bone health, lactose intolerance can also be associated with osteo-paenia in old people (Corazza et al., 1995). A report suggests that by 2020, half of all American citizens older than 50 will have low bone mass and be at risk for fractures from osteoporosis if appropriate dietary and other precautions are not followed (Carmona, 2006). Therefore, excluding milk from diet has adverse effects on health. 

The environmental benefits are (1) elimination of dairy product wastes and (2) better use of products. The benefits for the consumer are (1) a large number of adults (app. 20%-30% in the United States) are lactose intolerant, (2) many individuals (lactose intolerant) can now enjoy the nutritional benefits and sensory pleasme of dairy products without gastrointestinal side effects, and (3) a large number of people can select lactose-free or low-lactose dairy products or can add conunercially available lactase to dairy products in their homes. 

Silanized and glutaraldehyde-activated sub-micron ferrite particles have been used to immobilize j3-D-galactosidase. The immobilized enzyme was used for the hydrolysis of lactose in whole milk, from which the enzyme is readily recovered magnetically. The immobilized j3-D-galactosidase is of potential industrial importance hydrolysis improves some processed dairy products and there are also nutritional products requiring modification for people with lactose intolerance. 

Mcdonough, F. E., Hitchins, A. D., Wong, N. R, Wells, R, BodweU, C. E. (1987). Modification of sweet acidophilus milk to improve utilization by lactose-intolerant persons. American Journal of Climcal Nutrition, 45, 570-574. 

Anonymous, 1978, Nutritional significance of lactose intolerance, Nutr Rev, 36 133. 

Lactose intolerance is of practical concern in developing countries, as well as in school lunch programs, where milk is commonly used in attempts to correct or avoid serious nutritional problems. 

Nutritional Value of Milk Products. Milk is considered one of the principal sources of nutrition for humans. Some people are intolerant to one or more components of milk so must avoid the product or consume a treated product. One example is intolerance to lactose in milk. Fluid milk is available in which the lactose has been treated to make it more digestible. The consumption of milk fat, either in fluid milk or in products derived from milk, has decreased markedly in the 1990s. Whole milk sales decreased 12% between 1985 and 1988, whereas the sales of low fat milk increased 165%, and skimmed milk sales increased 48% (35). Nutritionists have recommended that fat consumed provide no more than 30 calories, and that consumption of calories be reduced. Generally, a daily diet of 2000—3000 cal/d is needed depending on many variables, such as gender, type of work, age, body responses, exercise, etc. Further, there is concern about cholesterol [57-88-5] and density of fat consumed. Complete information on the nutritive value of milk and milk products is provided on product labels (36) (see also Table 4). 

The nutritional and physiological effects of lactose in the diet have become of major interest to health professionals and the public with the finding that about 70% of the world population has low levels of lactase activity in the intestine and, in many cases, an intolerance to lactose. A voluminous literature has developed (Delmont 1983 Renner 1983 Paige and Bayless 1981). Most problems with lactose digestion are attributable to the lactose molecule, but others may arise from the galactose moiety liberated on hydrolysis. 

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