FAT SOLUBLE VITAMINS

1. FAT SOLUBLE VITAMINS

2. There are 4 fat soluble vitamins... VITAMINS A, D, E, & K. Vitamins are organic substances in food, that are needed in very small amounts for growth and for maintaining good health. There are vitamins that dissolve in water, and 4 vitamins that dissolve in fat: A, D, E, & K The 4 fat soluble vitamins are absorbed by fat globules, allowing them to travel through the intestinal walls and into the bloodstream. Largest amounts of fat-soluble vitamins are found in fatty foods and fish-liver oils.

3. There are 4 fat soluble vitamins... A, D, E, & K Fat malabsorption syndromes or bowel diseases (e.g., cystic fibrosis, ulcerative colitis, cholestatic liver disease, Crohn's disease) are associated with poor absorption of these vitamins. Absorption of fat-soluble vitamins takes place in the small intestine and depends on the presence of bile and pancreatic juices. Excess vitamins are stored in the liver and adipose (fatty) tissues of the body. Fat-soluble vitamins are generally excreted more slowly than water-soluble vitamins. Fat-soluble vitamins are not destroyed by normal cooking methods. They are stable to heat and light. They are destroyed by alkalis, such as baking soda. Some cooks add small amounts of baking soda when cooking vegetables to mellow harsh flavors and brighten colors.

4. Vitamin A is also known as retinol. Vitamin A... It is present in many animal products, and is readily absorbed from those dietary sources in the small intestine. Plants do not contain vitamin A, but many dark-green or dark-yellow plants contain carotenoids that are ‘precursors’ of Vitamin A. They can be converted to Vitamin A (retinol) within the intestinal mucosa just prior to absorption. Carotenoids are yellow, orange, and red pigments present in plants. Green vegetables also contain carotenoids, though the pigment is masked by the green pigment of chlorophyll. Beta-carotene is the name of a carotenoid.

5. Sources of Vitamin A... Vitamin A can be artificially added to milk and fortified cereals.

6. Recommended dietary allowances... Carotenoids are less easily absorbed than retinol and must be converted to retinol by the body. The most recent international standard of measure for vitamin A is retinol activity equivalents (RAE).

7. Primary functions of Vitamin A... 1. Maintains and strengthens the skin 2. Maintains health of specialized tissues such as the retina of the eye 3. Maintenance of the mucosal tissues and secretions, which in turn are responsible for normal functioning of the immune system; 4. Normal bone development 5. Maintenance of the reproductive system: required for sperm production in the male and regulate reproductive cycles in the female.

8. Excess Vitamin A in the diet... Excess Vitamin A is stored in the liver. In a well-nourished person, there may be a 2 - 12 month supply stored at any given time. A large surplus will accumulate in the liver and may be harmful. Such excessive intakes are less likely to result from over-eating than through the over-use of manmade vitamin pills or dietary supplements. Overdoses of manmade Vitamin A is called ‘Hypervitaminosis A’. Side effects of vitamin A excess/overdose include nausea, itchiness, irritability, vomiting, headaches, menstrual problems, dizziness, pimples, and birth defects. Long term vitamin A overdose can lead to liver damage, pain in the muscles and bone, and headaches.

9. Vitamin A deficiency... Xerophthalmia (zîr'əf-thăl'mē-ə) is a major cause of preventable blindness in children, especially in developing countries. It is an inflammation of the cornea (the clear covering of the eye). Bitot's Spots (′bē·tōs ′späts) are distinct elevated white patches on the conjunctiva, the membrane that covers most of the visible part of the eye. Night Blindness or Nyctalopia (nĭk'tə-lō'pē-ə)or is a condition making it difficult or impossible to see in dim light. Zinc deficiencies interfere with Vitamin A metabolism. Vitamin A deficiencies exacerbates iron-deficiency-anemia. Chronic alcohol consumption depletes liver stores of vitamin A. Vitamin A deficiency causes hardening and roughening of the skin, acne, birth defects, and degeneration of mucous membranes.

10. Normal (on the right) and vitamin A-deficient rat (on the left). Deficiencies result in a dryness and soreness which causes the eye lid to cake and to stick together.

11. Vitamin D is another fat-soluble vitamin. It is essential for maintaining normal calcium metabolism. Vitamin D can be synthesized by humans in the epidermis of the skin upon exposure to ultraviolet-B (UVB) radiation from sunlight, or it can be obtained from the diet. Vitamin D... Vitamin D works hand-in-hand with calcium. Neither can work alone.

12. Sources of Vitamin D... As little as 5-10 minutes of sun exposure on arms and legs or face and arms three times weekly between 11:00 am and 2:00 pm during the spring, summer, and fall should provide a light-skinned individual with adequate vitamin D and allow for storage of any excess for use during the winter with minimal risk of skin damage. Vitamin D is found naturally in very few foods: some fatty fish (mackerel, salmon, sardines), fish liver oils, and eggs. In the U.S. and Canada, it is a common nutritional additive to milk, orange juice, and cereals. Check product labels. The “vitamin D winter” extends from mid-October to mid-March in the midwest, and this is the time to take Vitamin D supplements.

13. Recommended dietary allowances... The issue of sunlight exposure confounds the existing data on vitamin D requirements, making it impossible to accurately calculate daily needs. The Recommended Dietary Allowances, therefore, have be set with the assumption that no vitamin D is being synthesized in the skin through exposure to sunlight.

14. Primary functions of Vitamin D... 1. Vitamin D is essential for the efficient metabolism and utilization of calcium by the body. Maintenance of calcium levels within a narrow range is vital for normal functioning of the nervous system. 2. Works with calcium for bone growth and maintenance of bone density. 3. Adequate vitamin D levels may be important for decreasing the risk of high blood pressure. 4. Plays a role in insulin secretion under conditions of increased insulin demand.

15. Excess Vitamin D in the diet... Vitamin D toxicity, known as Hypervitaminosis D, induces abnormally high calcium levels (Hypercalcemia), which could result in bone loss, kidney stones, and calcification of organs like the heart and kidneys if untreated over a long period of time. Excessive exposure to sunlight does not lead to vitamin D toxicity. Excesses are usually attributed to overdoses of dietary supplements. Like Vitamin A, a surplus of Vitamin D is stored in the liver and body fat. An individual experiencing vitamin D poisoning may complain of weakness, fatigue, loss of appetite, nausea, and vomiting. In infants and children there may be growth failure.

16. Vitamin D deficiency... In infants and children, severe vitamin D deficiency results in the failure of bone to mineralize, a disease called Rickets. Rapidly growing bones are most severely affected by rickets. The growth plates of bones continue to enlarge, but in the absence of adequate mineralization, weight-bearing limbs (arms and legs) become bowed. Vitamin D deficiency causes muscle weakness and pain in children and adults. In adults it may develop into osteomalacia, a disease characterized by poorly calcified, softened bones. Vitamin D deficiencies increase the risk of osteoporosis, which is a progressive loss of bone density.

17. Risk Factors for vitamin D deficiency... There are numerous factors that place people at a higher risk of having a vitamin D deficiency: • Infants that are exclusively breast-fed • Individuals with dark skin, as they don’t synthesize Vitamin D as well as those with light skin • Elderly individuals, as they have reduced ability to synthesize Vitamin D when exposed to UVB radiation and they stay indoors more. • Individuals covering all exposed skin or using sunscreen whenever outside • People with malabsorption syndromes such as cystic fibrosis or cholestatic liver disease • People with inflammatory bowel disease, like Crohn’s disease • People who are obese. • People who live in cloudy climates or cities with contaminated air that may lack sufficient amounts of ultraviolet rays. • Individuals who consume mineral oil, and the fat substitute Olestra, as they interfere with absorption of Vitamin D. The application of sunscreen with an SPF factor of 8 reduces production of vitamin D by 95%.

18. The term vitamin E describes a family of eight antioxidants. Vitamin E... Alpha-tocopherol (ăl'fə-tō-kŏf'ə-rôl‘) is the only form of vitamin E that is actively maintained in the human body. Alpha-tocopherol is the form of vitamin E that appears to have the greatest nutritional significance, and is found in the largest quantities in the blood and tissue. The acai berry (ah-sī-ē) is a source of omega 6 fatty acids and alpha-tocopherol. The value of Vitamin E for topical skin care has not been verified. It may have some moisturizing qualities, but frequently causes an allergic reaction.

19. Sources of Vitamin E... Major sources of alpha-tocopherol in the American diet include vegetable oils (corn, olive, sunflower, safflower oils), nuts, whole grains, dark berry juices, and green leafy vegetables. Cooking foods at high temperatures destroys vitamin E.

20. Recommended dietary allowances...

21. Primary functions of Vitamin E... The main function of Vitamin E (alpha-tocopherol) is that of an antioxidant. An antioxidant is a substance that reduces or prevents damage. Free radicals are very reactive atoms or molecules that typically possess a single unpaired electron. They are formed in the body during normal metabolism and also upon exposure to environmental factors such as cigarette smoke, stress, alcohol, lack of sleep, poor diet, or pollutants. These free radicals cause destruction by trying to remove electrons from other molecules so they will have a matched pair. This destruction is called oxidation. Fats and some proteins are the target of free radical destruction. The result is damage to the cell membranes and accelerated aging. It is also linked to Alzheimer’s disease, cataracts, heart disease, Vitamin K usage, and cancer.

22. How antioxidants work... Now that the radical has two electrons, he is no longer free to do harm. More free radicals may be created as a result of tobacco, alcohol, stress, lack of sleep, poor diet, and pollution. This is the antioxidant named Vitamin E. He prevents the free radical from continuing his destruction, by giving him an extra electron to hold onto. This is a free radical with one unpaired electron. He is destroying fat and some proteins, and accelerating aging in a process called oxidation… while trying to find a second electron.

23. Excess Vitamin E in the diet... The risk of too much Vitamin E is low. Excess amounts are stored or most likely excreted. Doses of over 800 IU a day of vitamin E may interfere with the body's ability to clot blood, posing a risk to people taking blood thinners (anticoagulants).  Many surgeons recommend the discontinuation of Vitamin E supplements prior to surgery, to avoid the risk of uncontrolled hemorrhage.

24. Vitamin E deficiency... Vitamin E deficiency has been observed in individuals with severe malnutrition, some genetic defects, and fat malabsorption syndromes such as cystic fibrosis or cholestatic liver disease. Severe vitamin E deficiency results mainly in neurological symptoms, including impaired balance and coordination, injury to the sensory nerves, muscle weakness, and damage to the retina of the eye. Vitamin E deficiencies are rare. In fact, a symptomatic vitamin E deficiency in healthy individuals who consume diets low in vitamin E has never been reported. Excess Vitamin E can be stored in fatty tissues of the body.

25. Vitamin E … People in some European countries consume diets high in saturated fats. The French, for example, enjoy meals that include heavy sauces made with cream and butter. Their incidence of heart disease, however, is not nearly as high as people in the United States. How might you account for that? One idea relates to the amount of red wine they consume with their meals. It would contain an anti-oxidant… and perhaps counteracts the effects of the saturated fats.

26. Function of Vitamin K... Vitamin K is a fat-soluble vitamin. The "K" is derived from the German word "koagulation." Coagulation refers to the process of blood clot formation. Vitamin K is essential for the functioning of several proteins involved in blood clotting. When an injury occurs, the protein molecules (with names like Factor II or prothrombin, Factor VII, Factor IX, and Factor X)rapidly assemble and form the blood clot. The term thrombus or thrombosis refers to a blood clot.

27. Recommended dietary allowances... 1 cup dark green or green leafy vegetables per day would provide an adequate supply of vitamin K.

28. Sources of Vitamin K... The best dietary sources of vitamin K are green leafy vegetables such as spinach, broccoli, Brussels sprouts, cabbage and lettuce. Other rich sources are certain vegetable oils. Good sources include oats, potatoes, tomatoes, asparagus and butter. Lower levels are found in beef, pork, ham, milk, carrots, corn, most fruits and many other vegetables. A portion of the body's vitamin K is produced by bacteria living in the jejunum and ileum of the intestine rather than by dietary sources.

29. Excess Vitamin K in the diet... Although allergic reaction is possible, there is no known toxicity associated with high doses of the dietary (K1) or intestinally-produced Vitamin K (K2). You can overdose on synthetic Vitamin K (K3). Large doses of this form break down red blood cells and can lead to a jaundice condition and possibly even brain damage when given to infants or pregnant women.

30. Vitamin K deficiency... Vitamin K deficiencies are rare for two reasons... 1. part of the body’s needs of this vitamin are produced in the intestinal tract 2. Vitamin K is “conserved” in the body. That means it is recycled… it can be used over and over. The process is called the Vitamin K cycle. Easy bruising associated with Vitamin K deficiency. Adults at risk of vitamin K deficiency include those taking vitamin K anticoagulant drugs (warfarin, coumadin, heparin) that may be prescribed for blood clots in the legs and lungs. Individuals with significant liver damage or disease, and individuals with disorders of fat malabsorption may also be at increased risk of vitamin K deficiency. Large doses of vitamin A and vitamin E have been found to counteract the function of vitamin K and interfere with Vitamin K absorption.Long-term use of antibiotics may destroy the bacteria in the intestine that produce Vitamin K.

31. Symptoms of a Vitamin K deficiency include easy bruising and bleeding that may be manifested as nosebleeds, bleeding gums, blood in the urine, blood in the stool, tarry black stools, or extremely heavy menstrual bleeding. Vitamin K deficiency frequently occurs in newborn infants. Many babies in the U.S. get an injection of vitamin K at birth to avoid hemorrhagic disease, which is characterized by uncontrolled bleeding within the skull. Babies depend on this long-lasting injection until vitamin K-producing bacteria become established in their digestive tracts. Spontaneous subcutaneous hemorrhages in a chick fed a vitamin K deficient diet for 15 days. The bottom chick was fed an adequate diet and is the same age.

32. Excess doses of Vitamin K... Excessive intake of vitamin K rarely occurs. Excess doses, those greater than 1000 times the requirement, can promote thrombogenesis (formation of blood clots) and hemolysis (red blood cells are destroyed faster than bone marrow can produce new ones). These doses of vitamin K can also increase risk of jaundice. Unless medically prescribed, Vitamin K should be consumed only from food sources to prevent toxic levels. Blood clot pictures: Top: Swelling and discoloration of the leg are signs of deep vein thrombosis, also known as a blood clot.Bottom: A blood clot that travels to the lungs is called pulmonary embolism, and can be fatal without emergency treatment.

33. FAT SOLUBLE VITAMINS THE END