By Jennifer Turley and Joan Thompson Fat Soluble Vitamins By Jennifer Turley and Joan Thompson © 2013 Cengage A D E K

Presentation Overview Comparison of vitamins in the body. Diagnosing deficiency and toxicity. The fat soluble vitamins, A, D, E, K. Notable health implications. Vitamin A Vitamin D Vitamin E Vitamin K Chemical Forms. Intake Need. Functions. Deficiency. Toxicity. Food Sources.

Comparison of Vitamins in the Body Vitamin A Vitamin D Vitamin E Water Soluble: absorbed into blood stream directly, circulate, travel, and stored in water compartments, excrete in urine, without intake deficiency signs and symptoms occur more quickly, toxicity is possible though shorter lived when intake is normalized. Vitamin K Thiamin Vitamin C Riboflavin B12 Pantothenic Acid Biotin Niacin Folate B6 Choline Fat Soluble: absorbed into lymph, many require protein carriers, associate with fat, not readily excreted, without intake deficiency signs and symptoms occur more slowly, toxicity is possible and longer lived even when intake is normalized.

Diagnosing Nutritional Deficiency or Toxicity Dietary records: Demonstrate low/high intake and/or confirm a metabolic or physiological problem that creates an altered need. Clinical deficiency or toxicity symptoms: Are compatible with low/high dietary intake or altered need. Biochemical tests: Such as blood levels, tissue levels & urine levels demonstrate low/high body levels of the nutrient. Nutrient supplementation: Serves as biological evidence by correcting the deficiency signs & symptoms. For toxicity, removal of the excess.

The Fat Soluble Vitamins D E K

Vitamin A Chemistry A family of compounds including: Retinol, Retinal, Retinoic acid Pro-Vitamin A carotenoids like beta-carotene Retinyl Esters (animal foods) Beta-Carotene (plant foods) Retinal (vision) Retinol (reproduction) Retinoic Acid (Growth Regulator)

Vitamin A Functions Vision Internal & external surface linings (epithelial cells) Growth Reproduction Embryonic development Gene expression Immune function Provitamin A forms have antioxidant properties

Vitamin A Deficiency vs Toxicity (<66% of DRI) Approx. <500 µg RE/day Adequacy DRI: 700-900 µg RE/day RDI: 5,000 IU Toxicity (>UL) >3,000 µg RE/day Hypovitaminosis A   Bone & tooth: Impaired growth Central Nervous System: Night blindness, complete blindness (Xerophthalmia) GI System: Diarrhea Immunity: Depressed immunity, more infections Skin: Hyperkeratosis (thickened skin) Normal vision, gene expression, reproduction, embryonic development, epithelial cell maintenance, growth, and immune function Bone & tooth: Decreased bone mineral density Central Nervous System: Headache, vertigo GI System: Nausea and vomiting, liver abnormalities Neuro-Muscular: Incoordination Skin: orange color with excess beta-carotene Other: Retinoid embryopathy 25 mg beta-carotene (pro-vitamin A is safe to take daily if you are not a smoker or drinker). Toxicity possible with supplements or acne medications . Pg 229 Adult deficient, adequate, toxic values

Vitamin A: Food Sources Retinol: (animal) Fortified milk, cheese, butter, margarine Eggs Liver  Beta-Carotene: (Plant) dark green leafy vegetables broccoli, deep orange fruits, & vegetables

Vitamin A in Foods Adult DRI: 700-900 µg RE/day

Vitamin D Chemistry Synthesis & Functions REGULATES Ca-P Balance Increases bone mineralization Increases intestinal absorption of calcium Increase phosphorus excretion Antiproliferative Prodifferentiation Pg 230 vitamin D synthesis for detailed review of pathophysiology.

Vitamin D Deficiency vs Toxicity There is an epidemic of vitamin D deficiency Deficiency (<66% of DRI) Approx. <3 µg/day Adequacy DRI: 15 µg/day RDI: 400 IU = 6.5 µg Toxicity (>UL) >50 µg/day Rickets (children) Osteomalacia (adults) Bone & tooth: poor growth, bowed legs, soft bones, pigeon chest, knocked knees, and malformed teeth in children. Porous bones in adults. Cardio-Vascular: increased circulating levels (PTH) and (AlkP) and decreased circulating levels of serum phosphorus GI System: Decreased calcium absorption Normal calcium and phosphorus balance and cell metabolism Hypervitaminosis D characterized by high levels of 25(OH)D from supplementation Cardio-Vascular: High blood calcium Central Nervous System: Weakness GI System: Nausea, vomiting, anorexia Other: Kidney stones, increased thirst, urination, and urinary calcium Needs are based upon an inadequate exposure to sunlight. Sunlight not implicated in toxicity. Adult deficient, adequate, toxic values

Vitamin D: Sources Fortified products like milk, margarine, & some cereals Eggs & fatty fish Self-synthesis with unprotected peak sunlight exposure

Vitamin D in Foods Adult DRI: 15 µg/day

Vitamin E Chemistry A family of alpha, beta, gamma, delta tocopherols & tocotrienols. Alpha-tocopherol is believed to be the most active form.

Vitamin E Functions Membrane Antioxidant & Stabilizer And at the molecular level Donates electron wihtout becoming reactive itself.

Vitamin E Deficiency vs Toxicity (<66% of DRI) Approx. <10 mg/day Adequacy DRI: 15 mg/day RDI: 30 IU Toxicity (>UL) >1,000 mg/day Premature infants: hemolytic anemia Adults: not well characterized Normal cell membrane integrity, reduced oxidative stress, and molecular functioning Relatively nontoxic Toxicity with supplements Interferes with vitamin K’s role in blood clotting, augmentation of anti-blood clotting medication and increases hemolysis Adult deficient, adequate, toxic values

Vitamin E: Food Sources Nuts Seeds Plant oils Wheat germ Fortified cereals Vegetables

Vitamin E in Foods Adult DRI: 15 mg/day

Vitamin K Chemistry Phylloquinone (K1) from plant sources & naphthaquinones (K2, multiple forms) from animal sources & gut bacteria.

Vitamin K Deficiency vs Toxicity (<66% of DRI) Approx. <60 µg/day Adequacy DRI: 90-120 µg /day RDI: 90 µg Toxicity (>UL) Not Determined Cardio-Vascular: Increases clotting time, hemorrhaging with cut or injury Normal blood clotting & bone metabolism Poorly described in adults GI System: High levels from supplemented menadione causes jaundice and liver damage in infants Interference with anti-blood clotting medication Adult deficient, adequate, toxic values

Vitamin K: Sources Green leafy & cruciferous vegetables Soybeans Some plant oils Vitamin K is made by bacteria in the gastrointestinal tract

Vitamin K in Foods Adult DRI: 90-120 µg/day

Summary Diagnosing & confirming a nutrient deficiency or toxicity requires a diet analysis, clinical evaluation, biochemical analysis, & evaluating the response to corrected intake levels. Toxicities and deficiencies take longer to develop for fat soluble vitamins as compared to water soluble vitamins. The fat soluble vitamins are grouped by their solubility in oil. The fat soluble vitamins have specific chemical forms & functions in the body. DRIs exist for essential fat soluble vitamins: A, D, E, & K. Deficiency & toxicity signs & symptoms are unique for each of these nutrients as are their food sources. References for this presentation are the same as those for this topic found in module 5 of the textbook