Lactose intolerance occurs when the body is unable to fully digest lactose, a sugar found in milk and milk products, due to a deficiency of the enzyme lactase. Symptoms include abdominal pain, bloating, diarrhea and flatulence. While infants produce lactase, levels typically decline after weaning in many populations worldwide. The condition can be managed by consuming smaller amounts of dairy, lactose-reduced dairy products, or supplements containing lactase enzymes. It is important for those with lactose intolerance to ensure adequate calcium and vitamin D intake through alternative food sources or supplements.

1. Lactose Intolerance
Dr. Yousef Elshrek

2. • Milkandmilkproductscontainhighconcentrationsofthe
disaccharidelactose(galactose andglucoselinkedbyabeta-
galactosidebond).

3. • Intestinalabsorptionoflactoserequiresthatthedisaccharide
behydrolyzedtoitscomponentmonosaccharaides,bothof
whicharerapidlytransportedacrossthesmallbowelmucosa.
• Lactase nonpersistence results in incomplete
digestion of an ingested load of lactose; hence
lactose is malabsorbed and reaches the colon.
• If sufficient lactose enters the colon, the
subject may experience symptoms of
abdominal pain, bloating, excess flatulence,
and diarrhea, a condition known as lactose
intolerance (LI).

4. Symptoms of Lactose Intolerance
Abdominal pain
Bloating
Diarrhoea
Nausea,
Vomitting flatulence

5. • A brush border beta- galactosidase, lactase, carries
outthishydrolysis.
• While infants virtually always have high
concentrations of lactase, sometime after weaning a
genetically programmed reduction in lactase
synthesis results in very low lactase activity in some
adult subjects, a situation known as lactase
nonpersistence.
• Diseases of the small bowel mucosa (infection, celiac
disease) may also be associated with low brush
border lactase, with resultant lactose malabsorption
(LM)andLI.

6. in lactase persistence lactase phlorizin
hydrolase in the brush border ..

8. World wide of populations that have
primary lactase deficiency
• The percentage of populations that have
primary lactase deficiency are considerable
throughout the world
• It Estimated that the following percentage of
specific ethnic are considered to be lactase
deficient
1. 85 – 100 of Asian
2. 80 – 100% of American Indians
3. 60 – 80 % of Africans
4. 50 – 60 % of Latinos
5. 2 - 15 % of Northern Europeans

9. Occurence of lactose-intolerance

10. • The amount of lactase available at
birthanddecreasewithage
• Yet, lactose-intolerant adults
began their lives drinking milk
from a bottle or breast and
digesting it completely.
• Babies produce the enzyme
lactase in their small intestine.
This enzyme breaks down
lactose.
• Therefore: Babies are lactose
tolerant

11. • Secondary lactase deficiency canoccur atthe
following:-
1. Disease andInfection
2. Injury tosmallIntestine
3. Surgery
4. Malnutrition

12. How is lactose intolerance managed?
• You can change your diet to manage your
symptoms.
• Most people with lactose intolerance do not
have to give up milk or milk products.
• You may be able to tolerate milk and milk
products 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 milk
products to your diet and see how you feel

13. • Eat milk products that are easier for people
with lactose intolerance to digest, such as
yogurt and hard cheeses like cheddar and
Swiss
• You can also use over-the-counter products
that may help you digest milk and milk
products.
• You can take a tablet that contains the lactase
enzyme when you eat foods that contain
lactose Add liquid lactase drops to liquid milk
products

14. • You can also find lactose-free and lactose-reduced milk and
milk products at the grocery store.
• These products have the same nutrients and benefits as
regular milk.

15. How will I know if a food has lactose?
• Lactose is found in milk and all foods made with
milk, such as
1. Ice cream
2. Cream
3. Butter
4. Cheese
5. Cottage cheese
6. Yogurt
• Rarely, people with lactose intolerance are
bothered by small amounts of lactose.
• Canned, frozen, packaged, and prepared foods
contain small amounts of lactose.

16. • Thesefoodsinclude
1. Breadandotherbakedgoods,pancakes,biscuits,
cookies
2. Preparedorfrozenbreakfastfoodssuchasdoughnuts,
frozenwafflesandpancakes,toasterpastries,and
sweetrolls
3. Boxedbreakfastcereals
4. Instantpotatoes,soups,andbreakfastdrinks
5. Potatochips,cornchips,andotherpackagedsnacks
6. Preparedmeats,suchsausage,hotdogs,andlunch
meats
7. Margarine
8. Saladdressings

17. 9. Liquid and powdered milk-based meal replacements
10. Protein powders and bars
11. Candies
12. Non-dairy liquid and powdered coffee creamers
13. Non-dairy whipped toppings
14. Look for certain words on food labels. These words
mean the food has lactose in it:
• Milk
• Lactose
• Whey
• Curds
• Milk by-products
• Dry milk solids
• Non-fat dry milk powder

18. How will I get the calcium I need?
• Milk and milk products are the most common
sources of calcium. Calcium is a mineral the body
needs for strong bones and teeth. If you are
lactose intolerant, make sure you get enough
calcium each day. Other foods contain calcium,
such as
1. Canned salmon or sardines with bones
2. Broccoli and other leafy green vegetables
3. Oranges
4. Almonds, Brazil nuts, and dried beans
5. Soy milk and tofu
6. Products with added calcium, such as orange juice

19. • Toabsorbcalcium,yourbodyneedsvitaminD.
• BesuretoeatfoodsthatcontainvitaminD,suchaseggs,
liver,andcertainkindsoffishlikesalmon andtuna.Also,
gettingenoughsunhelpsyourbodymakevitaminD.
• VitaminDisaddedtosomemilkandmilkproducts.
• Ifyou’reabletodrinksmallamountsofmilkoreatyogurt,
choosevarietiesthathavevitaminDadded.
• It’shardtogetenoughcalciumandvitaminDevenifyou
eatanddrinkmilkandmilkproducts.
• Talkwithyourdoctorabouthowtogetcalciumandvitamin
Dinyourdiet.
• Askifyoushouldalsotakeasupplementtogetenough
calcium,vitaminD,orothernutrients.

20. Points to Remember
1. Lactoseintolerancemeansyouhavetroubledigestinglactose.
2. If youhavelactose intolerance,youmaynotfeelwellafteryou
eat or drink milk and milk products. Many people with lactose
intolerance can tolerate small amounts of milk—4 ounces or
less—atatime,especiallywithmeals.
3. You may be able to gradually add small amounts of milk and
milkproductstoyourdiet.
4. You can use over-the-counter products that may help you
digestmilkandmilkproducts.
5. If you are lactose intolerant, make sure you get enough
calcium each day. Talk with your doctor about how to get
enough calcium in your diet. Ask if you should take a calcium
supplement.