Human lactose intolerance

Lee CM, Hardy CM Cocoa feeding and human lactose intolerance. Am J Clin Nutr 49 840-844, 1989. 

Lactose, the milk sugar, is a reducing disaccharide consisting of glucose and galactose moieties. The estimated annual worldwide availability of lactose as a byproduct from cheese manufacture is several million tons [1,2], but only about 400 000 t/a lactose is processed further from cheese whey [3], Non-processed whey is an environmental problem due to its high biochemical and chemical oxygen demand [2], The use of lactose as such is limited by two main factors relatively low solubility of lactose in most solvents and lactose intolerance in human body [1]. 

Food intolerance occurs when a food ingredient cannot be metabolised. The commonest food intolerance is lactose intolerance. This occurs when the enzyme lactase is absent. This happens when humans do not consume milk after weaning a state which is the norm in most of Asia. Thus it is possible that the bulk of the world s population is lactose intolerant. 

Some individuals are unable to metabolise lactose and are lactose intolerant. This is because they lack the enzyme lactase that is needed to metabolise lactose. Lactose intolerance is common in those parts of the world where humans do not consume any dairy products after weaning. In practice this means in Asia, which means that most of the world s population might be lactose intolerant. It is possible to produce lactose removed skim milk. Another approach with lactose is to hydrolyse it to its constituent monosaccharides. As well as avoiding lactose intolerance this allows a syrup to be produced from cheese whey. These syrups are offered as an ingredient for toffees and caramels. 

Enzymes are involved in many functions of the human body, including digestion and metabolism. For example, the enzyme lactase is responsible for catalyzing the breakdown of lactose, a sugar found in milk. People who are lactose-intolerant are usually missing lactase, or they have insufficient amounts. If you are lactose-intolerant, you can take commercially produced supplements that contain lactase. 

Human disorders and conditions are sometimes caused by the lack of an enzyme. For example, lactose intolerance is caused by low concentrations of lactase, an enzyme that breaks down lactose (the sugar in milk). Find out about lactose intolerance or another condition that is caused by a missing enzyme. How are the conditions diagnosed Have treatments been developed How effective are the treatments ... 

T Lactose intolerance, common among adults of most human populations except those originating... 

Today, the lactase market is primarily for solving the lactose intolerance problem in human diets. The tailoring of enzyme preparations continues and lactase may still be developed into a big profit item. 

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. 

Lactose Intolerance (Milk Intolerance) Lactose intolerance is the most common disorder of carbohydrate absorption. Lactase deficiency occurs in the majority of human adults throughout the world and appears to be genetically determined. The prevalence is high in persons of African and Asian ancestry ( 65%) and low in persons of Northern European ancestry. Lactase deficiency in which mucosal lactase levels are low or absent at birth... 

In full-term human infants, lactase activity attains peak values at birth and remains high throughout infancy. As milk intake decreases, lactase levels drop and lactose intolerance may develop. The extent of the decrease of lactase activity distinguishes lactose-tolerant from intolerant populations. 

In many humans the enzyme lactase, which digests the milk sugar lactose to galactose and glucose, disappears from the intestinal mucosal cells after age 4 to 6, when milk drinking usually decreases. This causes lactose intolerance, a condition in which ingestion of milk or lactose-containing milk products causes intestinal distress, because of bacterial action on the lactose that accumulates. 

Infant Formulas. A wide variety of infant formulas are marketed that all attempt to approximate the composition of breast milk. Some are based on soy or other proteins for inhmts who are lactose intolerant or aUei ic to milk products. None of the products are identical to breast milk, which is a species-specific formulation for human babies. Each animal species has a unique milk formulation for its young. Also, breast milk can supply maternal antibodies, which can protect the infimt from infection. For the foregoing reasons and others, many women choose to breast-feed. Some of these women will rely on breast pumps for regular or occasional use. 

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