Low-lactose diet

The proteinuria and aminoaciduria, and acidosis and glucosuria where they occur, are probably caused by reversible inhibition of some functions of the renal tubule. There would appear to be no structural damage to the kidney. However, 2 children developed nephrolithiasis while being treated with a low-lactose diet (B7, C5), The time course of events, when galactose is withdrawn from and returned to the diet, suggests that some metabolite of galactose accumulates in the cells of the renal tubules and has an inhibitory effect on the reabsorption of a number of substances. 

There is a remarkable degree of disagreement, among different workers, on the best type of low-lactose diet to feed to galactosemics. The basic principles are clear and generally accepted since the clinical manifestations of galactosemia are due to intoxication by galactose-1-... 

The value of any low-lactose diet can be judged only by the effect on the patients. On this basis all the above diets have achieved good results in some cases, none has been completely satisfactory. The results in young and severely ill infants are different from those in older and more moderately affected children, and the two groups are dealt with separately. 

Case B (c) Galactose 1-phosphate uridylyltransferase is an enzyme involved in conversion of galactose to glucose, which then can enter glycolysis. Absence of this enzyme leads to accumulation of galactose in the blood and excretion in the urine. A patient with this deficiency should be on a low-lactose diet (treatment 3). 

In addition symptomatic treatment with opiates, with bile acid binding resins in those with bile acid malabsorption, with milk free diets in those who are lactose intolerant, and with low fat diets may materially help relevant symptoms. 

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." ... 

Because /3-lactose is initially more soluble than ordinary lactose (a-lac-tose), it may be supposed that the i -form is utilized more efficiently in nutrition, but the opposite appears to be true. Young rats on a low-fat diet fail to survive when the only source of carbohydrate in the diet is either a-lactose or jS-lactose. Although alopecia occurs regardless of the form of lactose used, it occurs sooner and survival is shorter in rats fed jS-lactose. Whether or not the greater deleterious effect of the jS-lactose is due to a more rapid rate of hydrolysis and absorption does not seem to be known (S5). An industrial demand for jS-lactose has resulted in the development of practical processes for the manufacture of this sugar. (See Chapter IX, under Lactose.)... 

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. 

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. 

Fluid milk contains about 5 % of lactose. Lactose has low solubility and low sweetness, and a significant part of the world s population does not tolerate lactose in the diet. For these reasons the conversion of lactose to the component sugars, glucose and galactose would be worthwhile. Commercial lactases have been developed from lactose-fermenting yeasts and shown to have utility in the hydrolysis of lactose in a variety... 

With regard to patients with classical galactosemia off diet, the total antioxidant capacity was found to be low, and the activities of their erythrocyte membrane AChE, (Na-", K+) - ATPase and Mg -"-ATPase were remarkably reduced. Interestingly, these reduced enzyme activities were restored to normal when the patients followed their galactose/lactose-restricted diet and their total antioxidant capacity was increased reaching that of normal (Schulpis et al., 2005 Tsakiris et al, 2005b). 

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