• Intestinalabsorptionoflactoserequiresthatthedisaccharidebehydrolyzedtoitscomponentmonosaccharaides,bothofwhicharerapidlytransportedacrossthesmallbowelmucosa.• Lactase nonpersistence results in incompletedigestion of an ingested load of lactose; hencelactose is malabsorbed and reaches the colon.• If sufficient lactose enters the colon, thesubject may experience symptoms ofabdominal pain, bloating, excess flatulence,and diarrhea, a condition known as lactoseintolerance (LI).
Symptoms of Lactose IntoleranceAbdominal painBloatingDiarrhoeaNausea,Vomitting flatulence
• A brush border beta- galactosidase, lactase, carriesoutthishydrolysis.• While infants virtually always have highconcentrations of lactase, sometime after weaning agenetically programmed reduction in lactasesynthesis results in very low lactase activity in someadult subjects, a situation known as lactasenonpersistence.• Diseases of the small bowel mucosa (infection, celiacdisease) may also be associated with low brushborder lactase, with resultant lactose malabsorption(LM)andLI.
in lactase persistence lactase phlorizinhydrolase in the brush border ..
World wide of populations that haveprimary lactase deficiency• The percentage of populations that haveprimary lactase deficiency are considerablethroughout the world• It Estimated that the following percentage ofspecific ethnic are considered to be lactasedeficient1. 85 – 100 of Asian2. 80 – 100% of American Indians3. 60 – 80 % of Africans4. 50 – 60 % of Latinos5. 2 - 15 % of Northern Europeans
Occurence of lactose-intolerance
• The amount of lactase available atbirthanddecreasewithage• Yet, lactose-intolerant adultsbegan their lives drinking milkfrom a bottle or breast anddigesting it completely.• Babies produce the enzymelactase in their small intestine.This enzyme breaks downlactose.• Therefore: Babies are lactosetolerant
How is lactose intolerance managed?• You can change your diet to manage yoursymptoms.• Most people with lactose intolerance do nothave to give up milk or milk products.• You may be able to tolerate milk and milkproducts if you• Drink small amounts of milk—4 ounces or less—at a time• Drink small amounts of milk with meals• Gradually add small amounts of milk and milkproducts to your diet and see how you feel
• Eat milk products that are easier for peoplewith lactose intolerance to digest, such asyogurt and hard cheeses like cheddar andSwiss• You can also use over-the-counter productsthat may help you digest milk and milkproducts.• You can take a tablet that contains the lactaseenzyme when you eat foods that containlactose Add liquid lactase drops to liquid milkproducts
• You can also find lactose-free and lactose-reduced milk andmilk products at the grocery store.• These products have the same nutrients and benefits asregular milk.
How will I know if a food has lactose?• Lactose is found in milk and all foods made withmilk, such as1. Ice cream2. Cream3. Butter4. Cheese5. Cottage cheese6. Yogurt• Rarely, people with lactose intolerance arebothered by small amounts of lactose.• Canned, frozen, packaged, and prepared foodscontain small amounts of lactose.
9. Liquid and powdered milk-based meal replacements10. Protein powders and bars11. Candies12. Non-dairy liquid and powdered coffee creamers13. Non-dairy whipped toppings14. Look for certain words on food labels. These wordsmean the food has lactose in it:• Milk• Lactose• Whey• Curds• Milk by-products• Dry milk solids• Non-fat dry milk powder
How will I get the calcium I need?• Milk and milk products are the most commonsources of calcium. Calcium is a mineral the bodyneeds for strong bones and teeth. If you arelactose intolerant, make sure you get enoughcalcium each day. Other foods contain calcium,such as1. Canned salmon or sardines with bones2. Broccoli and other leafy green vegetables3. Oranges4. Almonds, Brazil nuts, and dried beans5. Soy milk and tofu6. Products with added calcium, such as orange juice
Points to Remember1. Lactoseintolerancemeansyouhavetroubledigestinglactose.2. If youhavelactose intolerance,youmaynotfeelwellafteryoueat or drink milk and milk products. Many people with lactoseintolerance can tolerate small amounts of milk—4 ounces orless—atatime,especiallywithmeals.3. You may be able to gradually add small amounts of milk andmilkproductstoyourdiet.4. You can use over-the-counter products that may help youdigestmilkandmilkproducts.5. If you are lactose intolerant, make sure you get enoughcalcium each day. Talk with your doctor about how to getenough calcium in your diet. Ask if you should take a calciumsupplement.