Dr S Nishan Silva MBBS Vitamins Definition Chemically

Dr. S. Nishan Silva (MBBS)

Vitamins • Definition: – Chemically unrelated organic compounds that are essential for normal metabolism • Cannot be synthesized, therefore must be ingested

Vitamins (Fat Soluble) • Vitamin A, D, E, K (Water Soluble) • Vitamin C and the B vitamins – – – – B 1 -Thiamine Riboflavin B 3 -Niacin Pantothenic acid Biotin B 6 -pyridoxine B 12 folate

Vitamin deficiency • Gross deficiencies are recognized by clinical syndromes • Are seen in poorer areas • Seen in Western societies in special populations – Elderly, vegans, new immigrants, the very poor, alcoholism, malabsorption (hx gastric bypass), parenteral nutrition

Vitamin A • First fat soluble vitamin to be discovered • Part of compounds called retinoids • Essential for vision, immune response, epithelial growth and repair • Can store 1 year of reserve • RBP=retinol binding protein-bonds to Vitamin A in blood

Requirements • Males > 10 y need 1000 mcg • Females > 10 y need 800 mcg • only 40 -60% plant bioavailability vs 8090% of animal protein • Zinc and/or Iron deficiency can interfere with metabolism • LABS – -RBP, FBC, serum retinol(costly)

Vitamin A deficiency • Complications – Dry skin, dry hair, broken nails-may be first sign – Night blindness – Xeropthalmia-no tears-predisposes to blindness – Hyperkeratosis-goose bump skin

Vitamin A deficiency Night Blindness Imagine you are in the car at the left and this is what you see.

Car approaches, note sign on the right.

Normal vision Car passes. Notice distance down the road, signs.

Night Blindness Eye fails to adapt quickly to decreased light. Car passes. Notice distance down the road, signs.

Vitamin A deficiency. Human shoulder. Follicular hyperkeratosis. Goose flesh. Pustulation occurs and is confused with acne.

Bitot's spots are the buildup of keratin debris located superficially in the conjunctiva, which are oval, triangular or irregular in shape.

Xerophthalmia caused by a severe vitamin A deficiency is described by pathologic dryness of the conjunctiva and cornea

Vitamin K • • Found in green, leafy vegetables and oils Plays a role in coagulation cascade Body’s reserve lasts one week 85% absorbed in terminal ileum

Vitamin K deficiency • Def due to – chronic illness, multiple abdominal surgeries, liver or biliary disease, alcoholism, drugs: Antibiotics(cephalos) Coumadin, salicylates, sulfa • Clinical Manifestations – Bleeding, hematoma, ecchymosis

Easy Bruising Epistaxis Echymosis

It’s a brain of a baby. Vit K deficiency in man. Hemorrhagic disease of newborn. Reason for Vit K injection at birth.

Vitamin K deficiency • Labs: – Pt/Ptt (INR) – Vit K level (0. 2 -1 ng/ml) • RX – Replace Vit K IM( 10 mg/d) , SQ, or PO (5 -20 mg) – FFP( begin- 2 Units)

Vitamin D • Few foods contain Vit D (fatty fish and eggs) • Dermal synthesis or fortified foods (milk) are the main source • Two forms of Vitamin D– Ergocalciferol -Vit D 2 – Cholecalciferol-Vit D 3

Vitamin D Metabolsim • Vitamin D 3 is synthesized in the skin during UV light exposure • Vit D 3 from skin or diet is then hydroxylated in the liver, then kidneys to active form Vit D dihydrohycholecalciferol (calcitriol)

Prevalence (D Deficiency) • • MSK pain (unrecognized !!!!!!) Hospitalized pts Women being treated for OP CKD (usually 1, 25 DOH but also 25 OHD GI malabsorption Gastric bypass Cystic fibrosis Extensive burns

Vitamin D deficiency • Independent predictors – Low Vitamin D intake – Winter – Housebound status • Who should be tested? – Institutionalized or home bound – Suspected malabsorption – Evaluation of osteoporosis

Osteoporosis Postmenopausal women with low 25 OHD levels have lower bone densities (3)

Rickets

Vitamin D serum levels • Test to order: serum 25 OH Vit D (calcidiol) • Normal 30 -32 ng/ml(75 -80 mmol/L) • “levels of 28 -40 may lower the fracture risk” • Example definitions of deficiency – Vit D Insufficiency= 20 -30 ng/ml – Vit D Deficiency=< 20 ng/ml

Optimal intake • 1997 national academy of sciences recommendation: – 400 IU/d age 51 -70 – 600 IU/d age > 71 – However more recent data shows avg adult needs 800 -1000 IU/d to maintain level of 30 – Older persons confined indoors may have low levels even at this intake

Vitamin D supplementation • For every 40 IU of D 3 given, serum 25 -OH D increased by 0. 3 -0. 4 ng/ml • Rx for deficiency – PO: 50, 000 units of D 3 q week x 6 -8 weeks, then 8001000 IU daily – IM : D 3 (300, 000 IU) in 1 or 2 doses per year • Rx for Insufficiency – 800 -1000 IU of D 3 daily( will bring avg adult to serum level of 30 in 3 months) • Measure serum levels after 3 months of starting rx

Vitamin B 12 • Deficiency causes: – Neurologic disease – Megaloblastic anemia, pernicious anemia – May be important cause of hyperhomocysteinemia (CV disease, OP) • Subtle deficiency even without anemia may cause dementia and ? balance problems

B 12 Deficiency • Hematologic – Megaloblastic anemia – Pancytopenia (leukopenia, thrombocytopenia) • Neurologic – Paresthesias – Peripheral neuropathy – Combined systems disease (demyelination of dorsal columns and corticospinal tract) • Psychiatric – – Irritability, personality change Mild memory impairment, dementia Depression Psychosis • Cardiovascular – Possible increased risk of myocardial infarction and stroke

Megaloblastic Anaemia

Suboptimal B-12 deficiency • Caused by poor absorption and inadequate intake • Malabsorption-cobalamin unable to release from dietary proteins esp with low gastric acid secretions • Alcoholism

Peripheral Neuropathy

B 12 level • Normal-> 300 pg/ml cobalamin deficiency unlikely • Borderline 200 -300 -deficiency possible • Low < 200 -deficiency

Recommendations for B 12 supplementation • Older adults - 6 mcg daily • Vitamin supplements have 100 mcg/dose • May be inadequate dose in: – – – Elderly Atrophic gastritis Vegans Gastric bypass sx Alcoholics Poor dietary intake

Folic acid • Found in green leafy vegetables, fruits, cereals, nuts, mats • Folic acid (the supplement form) has same effect but more bioavailable than folate • Deficiency leads to megaloblastic anemia

Folic Acid in Pregnancy • Decreases risk of neural tube defect • Appears dose dependent - In one study 400 mcg decreased rate of NTD by 57% 5000 mcg decreased rate by 85%

Folic acid in Cardiovascular Disease • Elevated homocysteine associated with increased risk of CV disease • Folic acid, B 6, B 12 can decrease homocysteine

Vitamin C – Ascorbic Acid • Vitamin C is a water-soluble vitamin • You need vitamin C for the growth and repair of tissues in all parts of your body. • It helps the body make collagen, an important protein used to make skin, cartilage, tendons, ligaments, and blood vessels. • Vitamin C is needed for healing wounds, and for repairing and maintaining bones and teeth.

Vit C Deficiency • Dry and splitting hair; gingivitis (inflammation of the gums) and bleeding gums; rough, dry, scaly skin; decreased wound-healing rate, easy bruising; nosebleeds; and a decreased ability to ward off infection. A severe form of vitamin C deficiency is known as scurvy.

Vit C Deficiency • Low levels of vitamin C have been associated with a number of conditions, including high blood pressure, gallbladder disease, stroke, some cancers, and atherosclerosis, the build-up plaque in blood vessels that can lead to heart attack and stroke.

• Recommended amounts – Men over 18 years: 90 mg – Women over 18 years: 75 mg • Treatment – 2 - 3 times per day, with meals, depending on the dosage. – Adults should take 250 - 500 mg twice a day for any benefit.

Vitamin E • Vitamin E - fat soluble compounds with strong antioxidant properties. • Isomers of tocopherol and torcoretinol • People aged 14 years or more - 15 mg per day

Vit E Deficiency • • • 1. Anemia 2. Poor Balance 3. Muscle Weakness 4. Sight Problems Nervous system problems – sensation loss, pain, and tingling – in the arms, hands, legs, and feet may signify vitamin E deficiency.

Treatment with Vit E • From 200 - 2400 IU daily depending on condition • Capsules for hair loss • Given for muscle cramps

Vitamin B 1 – Thiamin • Vitamin B 1, helps fuel by converting blood sugar into energy. • It keeps your mucous membranes healthy and is essential for nervous system, cardiovascular and muscular function. • Women should have 1. 1 milligrams every day, • and men should have 1. 5 milligrams every day.

Treatment with Thiamin • Mild deficiency - usual dose of thiamine is 5 -30 mg daily • severe deficiency can be up to 300 mg per day • As a dietary supplement in adults, 1 -2 mg of thiamine per day • 100 mg IM for treating and preventing symptoms of alcohol withdrawal (Wernicke -Korsakoff syndrome).

Vitamin B 2 - Riboflavin • Riboflavin (vitamin B 2) is manufactured in the body by the intestinal flora and is easily absorbed • Vitamin B 2 is required for the health of the mucus membranes in the digestive tract and helps with the absorption of iron and vitamin B 6. • RDA: 1. 2 Mg - 1. 7 Mg. Therapy : 25 - 50 Mg.

Vitamin B 3 - Niacin • Has 2 other forms, niacinamide (nicotinamide) and inositol hexanicotinate • Men 19 years and older: 16 mg (RDA) • Women 19 years and older: 14 mg (RDA) • Therapy : 100 Mg or more with meals (For alcoholics, Migrain)

Pellegra. Niacin deficiency. Dermatitis, diarrhea, dementia.

Same patient after niacin treatment.

Vitamin B 5 – Pantothenic acid • “anti-stress vitamin" • Vitamin B 5 plays an important role in the secretion of hormones, such as cortisone because of the role it plays in supporting the adrenal gland. • RDA: est 4 - 7 Mg daily. Therapy: 50 - 200 Mg

Vitamin B 5 Deficiency • Fatigue, headaches, nausea, tingling in the hands, depression, personality changes and cardiac instability • Frequent infection, numbness, paresthesia , muscle weakness and cramps. • Increased insulin sensitivity, lowered blood cholesterol, decreased serum potassium, and failure of adrenocorticotropin to induce eosinopenia.

Vitamin B 6 - Pyridoxine • Pyridoxine is required for the balancing of hormonal changes in women as well as assisting the immune system and the growth of new cells. • RDA : 1. 8 - 2. 2 Mg. Therapy : up to 200 Mg daily over several months.

Vitamin B 6 Deficiency • Irritability, nervousness and insomnia , general weakness, dermatitis and acne , asthma and allergies • Nails get ridged, an inflamed tongue , osteoporosis and arthritis. Kidney stones may also appear.

Biotin • Also called Vitamin B 7, Vitamin H • Foods include Swiss chard, raw egg yolk, liver, some vegetables and peanuts. • Hair loss, Diabetes. , Diabetic nerve pain, Brittle fingernails and toenails, Other conditions. • 30 mcg for adults over 18 years

Toxicity • Water soluble vitamins – toxic at thousands x the DV – Vitamin C-increased risk of kidney stonescontroversial • Fat soluble vitamins – Vit D- hypercalcemia at dose of 2000 IU/d – Vitamin A –pregnancy-teratogenic – Vitamin E- above 400 IU may be associated with all cause mortality

Toxicity • Vitamin A -HA, dizziness, blurred vision, clumsiness, birth defects, • Vitamin D-Constipation, weakness, anorexia, weight loss, confusion • B 3 -Niacin-Flushing, redness of skin, • B 6 -pyridoxine-Numbness, paresthesia, ataxia • Vitamin C-kidney stones • Folate-can mask B 12 deficiency