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Related to lactose: lactose intolerance


a sugar derived from the milk of mammals, which on hydrolysis yields glucose and galactose; used as a tablet and capsule diluent, a powder bulking agent, and as a component of infant feeding formulas. Many persons are intolerant to lactose as a result of hereditary deficiency of lactase.


A reducing disaccharide present in mammalian milk and consisting of a galactosyl residue linked B1,4 to a glucopyranose; obtained from cow's milk and used in modified milk preparation, in food for infants and convalescents, and in pharmaceutical preparations; in large doses, acts as an osmotic diuretic and as a laxative. Human milk contains 6.7% lactose.


/lac·tose/ (lak´tōs) a disaccharide occurring in mammalian milk, which on hydrolysis yields glucose and galactose; used as a tablet and capsule diluent, a powder bulking agent, and as a component of infant feeding formulas.


A white crystalline disaccharide, C12H22O11, found in milk, that may be hydrolyzed to yield glucose and galactose. Refined lactose obtained from whey is used in infant foods, bakery products, confections, and pharmaceuticals as a diluent and excipient. Also called milk sugar.


Etymology: L, lac + Gk, glykys, sweet
a disaccharide found in the milk of all mammals. On hydrolysis, lactose yields the monosaccharides glucose and galactose. Lactose is used as a laxative, a diuretic, and a component of formulas for infants. Also called lactin, milk sugar. See also lactase deficiency, lactose intolerance, sugar.


A reducing disaccharide that is hydrolysed by beta-galactosidase into d-galactose and d-glucose; it is synthesised by mammalian mammaries, and causes intolerance to milk products that occurs in some adults.


A disaccharide present in cow's milk and used in food for infants and convalescents and in pharmaceutical preparations; large doses act as an osmotic diuretic and as a laxative.
Synonym(s): milk sugar.


The main sugar in milk. It is broken down by the digestive enzyme lactase (beta-galactosidase) to galactose and glucose.
Lactoseclick for a larger image
Fig. 203 Lactose . The condensation reaction between galactose and glucose.



milk sugar

a DISACCHARIDE carbohydrate found in the milk of mammals. Lactose is produced by a CONDENSATION REACTION between galactose and glucose. See Fig. 203 .

The sugar can be broken into its component monosaccharides by LACTASE. Souring of milk is due to the conversion of lactose to LACTIC ACID by microorganisms present in the milk.


A sugar found in milk and milk products. Some people are lactose intolerant, meaning they have trouble digesting lactose. Lactose intolerance can produce symptoms resembling those of IBS.


n sugar extracted from milk, often used as a dilutent in the creation of homeopathic remedies and in nonmedicated tablets.


A disaccharide present in cow's milk and used in food for infants and convalescents and in pharmaceutical preparations.
Synonym(s): milk sugar.


a sugar derived from milk, which on hydrolysis yields glucose and galactose.

lactose digestion test
oral test of foal's ability to digest milk sugar.
lactose intolerance
inability to digest lactose in the diet because of the lack of the enzyme lactase in the small intestine. Clinical consequences are intestinal discomfort and diarrhea.
lactose tolerance test
a monitor of intestinal epithelial damage, similar to the starch digestion test. The test measures the rise in blood glucose at timed intervals after oral administration of lactose; essentially a test of disaccharidase efficiency of the gut.

Patient discussion about lactose

Q. can you be lactose intolerant just in the morning? if i drink milk or eat a dairy product in the morning i get nausous, vomit and have diarehha. but i eat dairy products in the evening and im fine. is it possible to be lactose intolerant just in the morning?

A. Not that I'm aware of.. You are either lactose intolerant or you're not. However, it depends on how much dairy products you eat, and perhaps you consume more dairy products in the morning, on an empty stomach, where it all absorbs, where as in the evening you might eat less and combine it with other food. I would suggest you dicrease the total amount of dairy you eat, in order to get rid of these symptms.

Q. lactose intolerant If you are lactose intolerant and you consume a dairy related product can it cause a fever?

A. No
Lactose Intolerance means you lack the enzyme to digest milk.
You get diarrhea NOT fever

Q. I am lactose intolerant. Can I have any other dairy food?

A. If you are lactose intolerant then you must avoid all lactose containing foods like milk, yoghurt & cheese. You can consume these dairy products If your intolerance is less or else you can have cultured yoghurt and lactobacillus milk as a better dairy option.

More discussions about lactose
References in periodicals archive ?
Coli only had one means of utilizing lactose, and that when this genetic activity was shut off, these bacteria would not be able to survive on lactose.
Results suggest that the chain length of the lactose fatty acid esters significantly influenced the oil-in-water emulsification properties.
As presented in Table 2, the moisture content levels were significantly lower in CSPJ samples prepared with sucrose than those of the samples prepared with lactose and those prepared with maltose (15.
It may be sufficient to explain to your patient that typically exposure to excipients within oral medications is small and does not cause problems for a patient with lactose intolerance or a milk allergy.
During the fermentation process, bacteria ingest lactose, which makes some products virtually lactose-free, (http://www.
This clinical research demonstrates that supplementation with the DDS-1 strain of Lactobacillus acidophilus, produced by Nebraska Cultures, is an important part of restoring balance and alleviating symptoms for lactose sensitive people," said Michael Shahani, chief operations officer for the company.
HOW LACTOSE INTOLERANCE IS DIAGNOSED, if someone presents with symptoms such as those listed above, several tests can diagnose lactose intolerance.
Hypotheses about the LCT gene mutation considered that good tolerance of lactose gave carriers of the gene advantages in the struggle for survival and allowed to spread widely.
Please don't exclude dairy lactose L inu products from your diet without consulting your doctor first.
Left untreated, lactose intolerance--the inability to digest lactose--can lead to nutritional deficiencies.