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• Vitamins


  Organic, essential nutrients required in tiny amounts to perform specific functions that promote growth, reproduction, or the maintenance of health and life
• Biotin (Vit B7)


  A coenzyme that carries activated carbon dioxide, plays an important role in energy metabolism, gluconeogenesis, fatty acid synthesis, and breakdown of certain fatty acids and amino acids
• Biotin Food Sources, Deficiency, and Toxicity

  • Widespread in foods (organ meats, egg yolks, soybeans, fish, whole grains)
  • Also produced by bacteria in the gut
  • Biotin deficiencies rarely occur
  • Symptoms of deficiency: skin rash, hair loss, and neurological impairment
  • No adverse effects from high biotin intakes have been reported
  • Biotin does not have an upper level (UL)
• Pantothenic Acid (Vit B5)


  Part of chemical structure of coenzyme A, plays many important roles in the body
• Pantothenic Acid Food Sources


  • Beef, poultry, whole grains, potatoes, and broccoli are particularly good sources
• Pantothenic acid is readily destroyed by freezing, canning, and refining processes
• Pantothenic Acid Deficiency and Toxicity

  • Deficiencies are rare, symptoms include fatigue, GI distress, and neurological disturbances
  • Deficiency causes "Burning feet syndrome"
  • No toxic effects have been reported, no UL
• Vitamin B6


  Occurs in three forms: pyridoxal, pyridoxine, and pyridoxamine, all of which can be converted to the coenzyme pyridoxal phosphate (PLP) which plays a role in amino acid, carbohydrate and fatty acid metabolism, conversion of tryptophan, and synthesis of heme, nucleic acids, and lecithin
• Unlike other water-soluble vitamins, Vit B6 is stored exclusively in the muscle tissue
• Vitamin B6 Deficiency Symptoms

  • Early symptoms: depression and confusion
  • Advanced symptoms: abnormal brain wave patterns and convulsions
  • Overall symptoms: scaly dermatitis and microcytic anemia (small-cell type)
• Vitamin B6 Toxicity Symptoms


  • Depression, fatigue, irritability, headaches, nerve damage causing numbness and muscle weakness
• Vit B6 Food Sources


  • Meats, fish, poultry, potatoes, legumes, green vegetables, and non-citrus fruits
• Vit B6 is destroyed by heat
• Vit B6 appears to be less bioavailable from plant-derived foods compared to animal-derived foods
• Folate


  Also known as folacin or folic acid, the primary coenzyme form is tetrahydrofolate (THF) which serves as part of an enzyme complex that transfers 1-carbon compounds, helps convert vitamin B12 to coenzyme form, synthesize DNA, and regenerate methionine
• Bound vs. Free Folate

  Foods deliver folate mostly in the "bound" form, the intestine prefers to absorb the "free" folate form, enzymes on the intestinal surfaces convert the bound folate to the free folate form
• Vit B12 is needed so that the folate coenzyme (THF) can function. Without Vit B12, folate can't function as a coenzyme
• Natural vs. Synthetic Folate

  Bioavailability of folate from supplements taken on an empty stomach ranges from 50 to 100%, folate from fortified foods and supplements are 1.7 times more available than naturally occurring folate from foods
• Effects of Folate Deficiency

  • Defects in the orderly formation of the neural tube during early pregnancy results in many central nervous system disorders and death
  • Increased need for folate during pregnancy
  • Supplement intake recommendation: one month before conception, continued through first trimester
  • Deficiency leads to neural tube defects (Spina Bifida) and congenital birth defects
• Folate deficiency impairs cell division and protein synthesis, both of which are critical to growing tissues
• Consequences of Folate Deficiency

  • Anemia (large immature red blood cells) and GI tract deterioration
• Of all vitamins, folate is the most susceptible to drug interactions
• Folate Toxicity


  • Naturally occurring folate from food sources don't cause harm
  • Excess folate from fortified foods or supplements can be harmful, thus UL has been established
• Folate Food Sources


  • Rich in legumes, green leafy vegetables, and fortified grain products
• Heat and oxidation can easily destroy folate
• Vitamin B12


  Vitamin B12 and folate depend on each other for activation, both activate each other by removing and receiving a methyl group, the regeneration of methionine and synthesis of DNA and RNA depend on both folate and Vit B12, Vit B12 protects and promotes the normal growth of nerve fibers
• Digestion and Absorption of Vit B12

  1. In the stomach, hydrochloric acid (HCL) and the digestive enzyme pepsin release Vit B12 from proteins

  2. Vit B12 passes to the small intestine and binds with a molecule known as the "intrinsic factor"

  3. Vit B12 and the intrinsic factor create a complex which is required for the absorption of Vit B12
• Vit B12 Absorption and Deficiency

  • Vit B12 is transported in blood by "specific binding proteins"
  • Deficiency is mostly due to inadequate absorption, not poor intake
  • Inadequate absorption typically occurs due to lack of HCL or intrinsic factor
  • Many people over 50 years of age develop "atrophic gastritis" which damages the cells of the stomach, reducing HCL and intrinsic factor production
  • Vit B12 deficiency caused by atrophic gastritis and lack of intrinsic factor is known as "Pernicious anemia"
  • Vit B12 deficiency leads to "Anemia of folate deficiency (large-cell type)"
  • Vegetarians are at high risk of Vit B12 deficiency
• Vit B12 Food Sources


  • Found almost exclusively from animal products (meats, fish, poultry, shellfish, milk, eggs, cheese)
• Vit B12 is destroyed by microwave heating (unlike other water-soluble vitamins)
• Vitamin C (Ascorbic acid)

  Serves as a cofactor, helping enzymes perform their jobs, acts as an antioxidant by easily losing electrons to defend against free radicals
• Vitamin C as an Antioxidant


  Vit C can give its electrons to stop free-radical damage and then receive them again to become activated, this "recycling" of Vit C is important for limiting losses and maintaining a reserve of antioxidants in the body, Vit C protects tissues from oxidative stress and enhances iron absorption
• Vitamin C as a Cofactor


  Vit C is a cofactor in collagen formation, hydroxylation of carnitine, conversion of tryptophan to serotonin, conversion of tyrosine to norepinephrine, and making hormones such as thyroxin
• Vitamin C Deficiency


  • Gums bleed easily around teeth, capillaries under skin break spontaneously, leads to "Scurvy" with symptoms of hemorrhaging, muscle degeneration, brown dry and rough skin, non-healing wounds, soft malformed and painful bones, anemia, infections, loose teeth, hysteria and depression, sudden death from massive internal bleeding
• Vitamin C Intake


  10 mg/day prevents obvious symptoms of scurvy, maximum absorption at 200 mg, smoking increases the need for Vit C
• Vitamin C Toxicity


  • Supplementation side effects include diarrhea and GI distress, UL=2000 mg/day, can interfere with medical regimens, high doses not recommended with certain medical conditions
• Vitamin C Food Sources

  • Abundant in fruits and vegetables, easily destroyed by heat and oxygen, raw fruits and vegetables have higher amounts compared to cooked, fruit juices must be stored properly to avoid damage by oxygen, used as an antioxidant by food manufacturers