1. Chapter 11
Fat Soluble Vitamins:
ADEK

2. Chapter 11 - FSV Characteristics of fat-soluble vitamins
Do not dissolve in water, but dissolve in fat or organic solvents.
Dietary fat soluble vitamins need bile for absorption.
The fat-soluble vitamins include vitamins A, D,E and K
Found in the fats and oils of foods.
Stored in the liver and fat tissue until needed
not readily excreted from the body.
Risk of toxicity.

3. Storage of vitamins in the body
Vitamins A, D and E:
These three fat-soluble vitamins can accumulate in the liver and fat tissue of the body and are not readily excreted. Long-term intakes more than the RDA can be toxic, particularly vitamins A and D.
Vitamin K:
The other fat-soluble vitamin, vitamin K, is readily excreted from the body.

4. Absorption & transport
The fat-soluble vitamins, like lipids are absorbed with dietary fat.
Bile aids in the absorption of fat-soluble vitamins.
The GI must function adequately for efficient uptake of fat-soluble vitamins.
Under normal conditions, healthy individuals will absorb 40-90% of fat-soluble vitamins.

5. Absorption & Transport
Fat malabsorption interfere with the absorption of FSV.
Unabsorbed fat is excreted as feces.
The following conditions adversely affect the uptake of fat-soluble vitamins:
Cystic fibrosis
Crohn’s disease
Celiac disease
Certain medications

6. Vitamin A Family of compounds called Retinoids:
Retinol – supports reproductive functions
Found in animal foods and nutrient supplements.
Can converted to retinoic acid and retinal in the body.
Retinal – Aid in vision
Retinoic acid – regulates growth
~90% of retinoids are absorbed
These are preformed Vitamin A – form that the body readily uses. Found only in animal sources

7. Provitamin A = carotenoids
Found in plant sources
Not biologically available until they are changed into one of the retinoids in the body
There are over 600 different carotenoids only 3 can be converted to vitamin A
Beta carotene (most common form)
Alpha carotene
Beta- cryptoxanthin
Accounts for 25 – 35 percent of dietary vitamin A consumed in the US

8. Essential for healthy eyes Promotes cell differentiation
Functions of Vit A
Essential for healthy eyes
Promotes cell differentiation
Determines what cell becomes in your body
Supports reproductive system, development of limbs, heart eyes and ears
Promotes bone and teeth growth
Play a role in immunity and preventing infections by creating white blood cells
Carotenoids, which act as antioxidants, decrease the damaging effects of free radicals.

9. Sources of Vitamin A Sources Preformed Vit A
Organ meats (liver), milk, cereals, cheese and eggs are the most popular sources of
Provitamin A (carotenoids)
Fruits: peaches, apricots, cantaloupes, mangoes, papaya
Vegetables: tomatoes, carrots, winter squash, sweet potatoes, broccoli, romaine lettuce, collard greens and spinach.
Adding as little as 1 tablespoon of vegetable oil to your diet can increase absorption of carotenoids by as much as 25%

10. Vitamin A
RDA – can be measured in micrograms of retinoic activity equivalents (RAE) or in international units (IU). 1 RAE = 3.3 IU
900 microgram for men
700 microgram for women
Upper limit 3,000 microgram/day
Deficiency
Night blindness – difficulty seeing at dusk, can’t adjust from day light to dark
Vitamin A deficiency is the main cause of non-accidental blindness (Xerophthalmia)
Many die after blindness as a result of infection.
The eye becomes prone to infections when the conjunctiva is damaged.
Infections can spread systemically throughout the body.

11. Figure 11.5: Vitamin A–Deficiency Symptom—Night Blindness.
These photographs illustrate the eyes’ slow recovery in response to a flash of bright light at night. In animal research studies, the response rate is measured with electrodes.

12. Toxicity
Hypervitaminosis A - is a condition that results from excessive intake of vitamin A from supplements
Cause defective physical development during early development of the fetus resulting in birth defects
Even 3X RDA vitamin A is considered risky during pregnancy.
Accutane is associated with congenital malformations result involving the head and brain.
FDA has recommended that women of childbearing years limit their vitamin A intake to 100% RDA

13. Toxicity
High consumption of vitamin A has been linked to osteoporosis and increased risk of fractures
Provitamin A carotenoids in foods are not toxic
Extra carotenoids are stored in the liver and in the fat under the skin, causing carotenodermia

14. Figure 11.7: Symptom of Beta-Carotene Excess—Discoloration of the Skin.
Fig. 11-7, p. 375

15. Vitamin D/calceferol
Also called the “sunshine vitamin” because it is made with the help of ultraviolet (UV) rays from sunlight
Vitamin D enters your body in an inactive form
The kidneys convert dietary vitamin D into the active form
Precursor = body’s cholesterol

16. Vitamin D/ calceferol Functions of Vit D Sources of vit D
Helps bone health by regulating calcium and phosphorus concentration in the blood
When blood concentration of calcium is low, vitamin D and parathyroid hormone signals the kidney to decrease excretion of calcium and phosphorous
Sources of vit D
Fortified milk, cereals, yogurt, fatty fish

17. Vitamin D Adequate Intake: 5 micrograms/day for 19-50 yr
Upper level: 50 micrograms/day

18. Vitamin D Deficiency Rickets in children (soft bones)
poor bone mineralization
Bowed legs
Unable to hold up their own weight when standing up
Recently researchers have found a rise in rickets among children,
linked to increase consumption of soft drinks
Limited outdoor activities
Fear of skin cancer
Air pollution reduces ultraviolet rays of the sun by as much as 60%

20. Vitamin D Osteomalacia - adult form of rickets
Occurs in women with decreased calcium and phosphorus intake
Causes bone weakness and pain
Can lead to osteoporosis

21. Vitamin D Toxicity
Hypervitaminosis D – associated with over-consumption of supplements
Increased calcium withdrawal in bones and intestines
Increased calcium and phosphorous
concentrations in the blood (hypercalcemia)
Increase calcium deposits in kidneys, lungs, blood vessels and heart

22. Vitamin E Vitamin E is an effective antioxidant
Prevent oxidation of lipids, vit A and LDL to prevent build-up in the arteries
Neutralize free radicals before they damage cell membranes
Prevents blood clotting in the blood by acting as anticoagulant
There are 8 different forms, only one is active in the body (alpha- tocopherol)
The synthetic is only half as active as the natural

23. Vitamin E Sources Polyunsaturated plant oils (vegetable oils)
Nuts and seeds
Leafy green vegetables
Fortified cereals
RDA:
Adults need 15 milligrams/day
Upper limit is 1,000 milligrams

24. Vitamin E
Deficiency
Erythrocyte hemolysis in premature infants (red blood cell destruction causing anemia)
Toxicity from synthetic form or fortified foods
increase risk of hemorrhage
A deficiency of vitamin K can increase the anticoagulant effect

25. Vitamin K There are two forms of vitamin K:
Menaquinone – synthesized by the intestinal tract
Phylloquinone – found in green plants
Functions
Essential for blood clotting
Vitamin K plays a role synthesizing clotting factors
Without vit k a simple cut on the finger would cause uncontrollable bleeding
Synthesis of bone protein (osteocalcin) that regulates blood calcium.

26. Vitamin K
Inadequate amount of vitamin K may contribute to osteoporosis, associated with increased risk of hip fractures
Sources
Intestinal bacteria can make vitamin K but not enough to meet all of the body’s needs
Leafy green vegetables
Cabbage family vegetables
Vegetable oils and margarine

27. Vitamin K Deficiency Toxicity
Newborn infants receive a single dose of vitamin K at birth because of a sterile intestinal tract to prevent hemorrhagic disease
Rare in healthy individuals
Toxicity
No known adverse effect from consuming too much vitamin K from food or supplement
Interferes with anticlotting medication (coumadin)

28. Recommendation for Vitamin K
Adequate Intake (based on amount that is consumed on average)
Infants: 2 – 2.5 microgram
Children: 30 – 55 microgram
Men: 60 – 120 microgram
Women: 60 – 90 microgram

29. Homework/extra credit
5 points Complete the vitamin/mineral evaluation form posted on the course website