Vitamins and Herbs

• Vitamins

  • Organic compounds
  • Required in minute amounts for growth and maintenance of health
  • Do not serve as a source of energy but are essential for energy transformation and regulation of metabolic processes
• Groups of vitamins

  • Fat-soluble
  • Water-soluble
• Fat-soluble vitamins

  • A
  • D
  • E
  • K
• Water-soluble vitamins

  • C
  • B complex (thiamine, riboflavin, niacin, pyridoxine, pantothenic acid, biotin, folic acid, cyanocobalamin)
• Except for vitamin B12, water-soluble vitamins undergo minimal storage in the body
• Fat-soluble vitamins can be stored in massive amounts
• Extensive storage of fat-soluble vitamins minimizes the risk for deficiency
• Extensive storage of fat-soluble vitamins increases the potential for toxicity if intake is excessive
• Vitamin A

  Also known as retinol, plays an important role in adaptation to dim light, embryogenesis, spermatogenesis, immunity, growth, and maintaining the structural and functional integrity of the skin and mucous membranes
• The only indication for vitamin A is prevention or correction of vitamin A deficiency
• Requirements for vitamin A

  1. Consuming foods that contain preformed vitamin A

  2. Consuming foods that contain provitamin A carotenoids
• Preformed vitamin A is present only in foods of animal origin
• Good sources of preformed vitamin A

  • Dairy products
  • Meat
  • Fish oil
  • Fish
• Sources of provitamin A carotenoids

  • Dark-colored carotene-rich fruits
  • Vegetables
• Night blindness is often the first indication of vitamin A deficiency
• In high doses, vitamin A can cause birth defects, liver injury, and bone-related disorders
• The UL for vitamin A is set at 3000 µg/day
• Vitamin A is highly teratogenic
• Excessive intake of vitamin A during pregnancy can cause malformation of the fetal heart, skull, and other structures of cranial–neural crest origin
• Pregnant women should not exceed the UL for vitamin A and should probably not exceed the RDA
• Sources of dietary vitamin E

  • Vegetable oils
  • Nuts
  • Wheat germ
  • Whole-grain products
  • Mustard greens
• High-dose vitamin E appears to increase the risk for hemorrhagic stroke by inhibiting platelet aggregation
• For every 10,000 people taking more than 200 IU of vitamin E daily for 1 year, there would be 8 additional cases of hemorrhagic stroke
• Vitamin K

  Required for synthesis of prothrombin and clotting factors VII, IX, and X
• Applications of vitamin K

  • Correction or prevention of hypoprothrombinemia
  • Control of hemorrhage caused by warfarin
• Vitamin K deficiency produces bleeding tendencies
• Severe vitamin K deficiency may cause spontaneous hemorrhage
• In newborns, intracranial hemorrhage is of particular concern due to vitamin K deficiency
• Vitamin K toxicity can cause hyperbilirubinemia, hemolytic anemia, and jaundice in newborns
• The oral form of vitamin K1 is not toxic in adults
• Vitamin C

  Participates in multiple biochemical reactions, including synthesis of adrenal steroids and regulation of the respiratory cycle in mitochondria
• Vitamin C is required for production of collagen and other compounds that comprise the intercellular matrix
• Vitamin C facilitates absorption of dietary iron
• The only established indication for vitamin C is prevention and treatment of scurvy
• Main dietary sources of vitamin C

  • Citrus fruits and juices
  • Tomatoes
  • Potatoes
  • Strawberries
  • Melons
  • Spinach
  • Broccoli
• Deficiency of vitamin C can lead to scurvy, a disease rarely seen in the United States
• Excessive doses of vitamin C can cause nausea, abdominal cramps, and diarrhea
• Vitamin B complex

  • Niacin
  • Riboflavin
  • Thiamin
  • Pyridoxine
  • Cyanocobalamin
  • Folic acid
• Niacin

  Used to reduce cholesterol levels and indicated for the prevention or treatment of niacin deficiency
• The syndrome caused by niacin deficiency is called pellagra