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Vitamins

Vitamins

  • Are organic compounds(meaning they always contain carbon)
  • Are needed in small quantities to sustain life
  • Must be obtained in the diet (are considered essential) because the human body either does not produce enough of them or any at all
  • There are 13 known vitamins:
  • A, B (there are 8 B vitamins), C, D, E, K
  • Are either water-soluble or fat-soluble
  • Fat-Soluble Vitamins
  • Are easier for the body to store than water-soluble vitamins
  • Are usually stored in the liver and adipose tissue
  • Because these vitamins are not readily excreted, they can build up to toxic levels! include vitaminsA, D, E, and K
  • Vitamin A
  • Is the name of a group of fat-soluble retinoids such as retinol, retinal, and retinyl esters
  • Is involved in:
  • Immune function
  • Vision(prevents night blindness as an essential component of rhodopsin—a protein that absorbs light in the retinal receptors)
  • Reproduction,
  • Bone health
  • Cellular communication
  • is available in 2 forms in the human diet: preformed vitamin A (retinol and its esterified form, retinyl ester) and provitamin A carotenoids
  • Preformed vitamin A:
  • is found in foods from animal sources such as fortified dairy products, fish, and meat (especially liver)
  • Provitamin A:
  • comes from leafy green vegetables, orange and yellow vegetables, tomato products, fruits, and some vegetable oils
  • By far the most important provitamin A carotenoid is beta-carotenefound in orange-yellow and dark green vegetables and fruits (including carrots, broccoli, cantaloupe, and squash)

  • Board Alert: Know that Inadequate vitamin A consumption can alter keratinization of oral tissues (‘oral keratinizing metaplasia’); however, vitamin C is much more influential in maintaining tissue integrity

  • Vitamin D
  • Promotes calcium absorption in the gut and maintains adequate serum calcium and phosphate concentrations to enable normal mineralization of bone
  • Is integral in immune function
  • Is produced endogenously(90% of vitamin D consumption) when ultraviolet rays from sunlight strike the skin and trigger vitamin D synthesis
  • Is naturally present in very few foods (examples include fatty fish such as salmon, tuna and sardines), is added to others (example fortified milk), and is available as a dietary supplement(D3)
  • Data suggest that vitamin D status could affect cancer risk
  • studies indicate that vitamin D plays a role in the prevention of colon, prostate, and breast cancers
  • Vitamin D Deficiency
  • can occur when:
  • Usual intake is lower than recommended levels over time
  • Exposure to sunlight is limited
  • The kidneys are compromised
  • Absorption of vitamin D from the digestive tract is inadequate
  • Vitamin D-deficient diets are associated with milk allergy, lactose intolerance, ovo-vegetarianism, and veganism

  • – Rickets and osteomalacia are the classic vitamin D deficiency diseases

  • Rickets
  • vitamin D deficiency in children
  • Is characterized by a failure of bone tissue to mineralize properly resulting in soft bones and skeletal deformities
  • Presents as bowed legs, enlarged head, deformed pelvis
  • The fortification of milk with vitamin D beginning in the 1930s has made rickets a rare disease in the United States, although it is still reported periodically, particularly among African American infants and children.
  • Osteomalacia
  • vitamin D deficiency in adults
  • Is weakening of the bones when calcium is leached from the bones to make up for insufficient absorption of vitamin D from the intestine
  • Presents as bowed legs, bent posture, bone pain, and muscle weakness

  • Osteoporosis is an example of a long-term effect of calcium and vitamin D insufficiency

  • Vitamin E (Tocopherol)
  • is the collective name for a group of fat-soluble compounds with distinctive antioxidant activities
  • naturally occurring vitamin E exists in eight chemical forms:
  • Alpha-, beta, gamma-, and delta-tocopherol and alpha-, beta-, gamma-, and delta-tocotrienol
  • These forms have varying levels of biological activity
  • Alpha- tocopherol is the only form that is recognized to meet human requirements
  • Functions as an antioxidant
  • Demonstrates anti-inflammatory processes, inhibition of platelet aggregation, and immune enhancement
  • Is found in numerous foods(nuts, seeds, and vegetable oils are among the best sources of alpha-tocopherol and significant amounts are available in green leafy vegetables and fortified cereals)
  • CAUTION:Vitamin E supplements have the potential to interact with several types of medications such as anticoagulant and antiplatelet medications (vitamin E can inhibit platelet aggregation and antagonize vitamin K-dependent clotting factors); this anticoagulation effect can also cause gingival bleeding if vitamin E levels are too high.
  • Vitamin D
  • ‘Vitamin K’ is the generic name for a family of compounds with a common chemical structure
  • These compounds include phylloquinone (vitamin K1) and a series of menaquinones (vitamin K2)
  • The most common sources of vitamin K in the U.S. diet are spinach***, broccoli, iceberg lettuce, and fats and oils (particularly soybean and canola oil)
  • Prothrombin (clotting factor II) is a vitamin K-dependent protein in plasma that is directly involved in blood clotting
  • For this reason, individuals who are taking anticoagulants need to maintain consistent vitamin K intakes
  • Water-Soluble Vitamins
  • Are not stored in the body
  • Any surplusbeyond what the body absorbs is usually excreted in the urine
  • The body needs a continuous supply through a steady daily intake
  • Are found in fruit, vegetables and grains
  • Unlike fat-soluble vitamins, water-soluble vitamins can be destroyed by heat or by being exposed to the air; they can also be lost in water used for cooking
  • Include vitamin C (‘ascorbic acid’) and all the B vitamins: Thiamin (B1), Riboflavin (B2), Niacin (B3), Pantothenic Acid (B5), Pyroxidine(B6), Biotin (B7), Folic Acid (B9), and Cobalamin (B12)
  • Vitamin C (‘Ascorbic Acid’)
  • Plays an important role in a number of bodily functions including the production of collagen
  • Is also a powerful antioxidant
  • Soitmay reduce the risk of some cancers
  • So ithelps repair tissue and reduce damage from inflammation and oxidation
  • People with adequate levels of vitamin C are thought to be better able to fight off infections compared to people with vitamin C deficiency
  • The best sources of vitamin C are fresh fruit and vegetables(examples include citrus fruits, strawberries, broccoli, potatoes, tomatoes, cantaloupe, spinach, sweet peppers)
  • Vitamin C Deficiency
  • Scurvyresults fromabnormal collagen synthesis
  • Clinical manifestations are bleeding gingiva, delayed wound healing, bleeding into joints, anemia
  • Occurs in certain groups of including:
  • People with low income(also referred to as ‘low socioeconomic status’ or ‘low SES’)tend to not buy foods with a high vitamin C content
  • People with a medical condition that affects the body's ability to digest and absorb food
  • Eg.Crohn's disease and ulcerative colitis
  • Older people who may eat a less varied diet
  • Smokers are at risk for vitamin C deficiency
  • Smoking affects the absorption of vitamin C from foods
  • Vitamin C is used up in the body more quickly in those who smoke
  • Pregnant and breast-feeding women because they need higher amounts of vitamin C
  • B Vitamins
  • All 8help the body convert food (carbohydrates) into fuel (glucose) to produce energy
  • Are often referred to as B-complex vitamins
  • Help the body metabolize fats and protein
  • Are needed for a healthy liver, skin, hair, and eyes
  • Help the nervous system function properly
  • Are needed for good brain function
  • Thiamin (Vitamin B1)
  • Is sometimes called an ‘anti-stress’ vitamin because it may strengthen the immune system and improve the body's ability to withstand stressful conditions
  • Plays a crucial role formingadenosine triphosphate (ATP), which every cell of the body uses for energy
  • Is present in most foods in small amounts
  • Is present in large amounts in pork, beef, poultry, and organ meats
  • Other good dietary sources of thiamin include whole-grain or enriched cereals and rice, legumes, wheat germ, bran, brewer's yeast, nuts, and blackstrap molasses
  • ThiaminDeficiency:

  • Beriberi (means ‘I can’t, I can’t’):

    :
  • People in the developed world usually do not get beriberi because foods such as cereals and breads are fortified with vitamin B1
  • Symptoms of Beriberi include:
  • Swelling, tingling, or burning sensation in the hands and feet
  • Confusion
  • Trouble breathing because of fluid in the lungs
  • Uncontrolled eye movements (nystagmus)

  • Wernicke-Korsakoff syndrome

  • Wernicke-Korsakoff syndrome is a brain disorder caused by thiamin deficiency often caused by malnutrition due to alcoholism and is characterized by memory problems and nerve damage
  • High doses of thiamin can improve muscle coordination and confusion but rarely improves memory loss
  • Riboflavin (B2)
  • Is naturally present in some foods, is added to some food products, and is available as a dietary supplement
  • Foods that are particularly rich in riboflavin include eggs, organ meats (kidneys and liver), lean meats, milk (NOTE: Because of light sensitivity, milk should be stored in opaque containers to prevent breakdown of B2)and fortified grains
  • Deficiency is extremely rare in the United States
  • Is an essential component of two major coenzymes (FAD and FADH2)
  • These coenzymes play major roles in energy production; cellular function, growth, and development; and metabolism of fats, drugs, and steroids
  • Niacin (B3)
  • Is made up of niacin and niacinamide
  • Is an essential component of two major coenzymes (NAD and NADH2)
  • Can be found in many foods such as enriched and fortified grains, sweet potatoes, yeast, lean meat, fish, milk, eggs, and green vegetables
  • The human body can also make niacin from the amino acid tryptophan
  • Is often found in combination with other B vitamins(including thiamin, riboflavin, pantothenic acid, pyridoxine, cyanocobalamin, and folic acid)
  • Is essential for more than 50 different bodily processesbut primarily supports cellular energy production
  • When in the form of nicotinic acid, helps support cardiovascular health
  • Vitamin B3 (Niacin) Deficiency(In the United States and other developed countries, niacin deficiency is rare and is typically found in alcoholics)

  • Pellegra:

  • Symptoms includeskin inflammation, dementia, and diarrhea (often remembered as the 4 Ds: dementia, diarrhea, dermatitis, death)
  • Pyridoxine (Vitamin B6)
  • Helps support adrenal function and maintain a healthy nervous system
  • supplementation may treat or improve memory loss, diabetes, asthma attacks, attention deficit-hyperactivity disorder (ADHD), kidney stones, lung cancer, acne, and atherosclerosis
  • Acts as a coenzyme in the breakdown and utilization of carbohydrates, fats, and proteins
  • Deficiency symptoms include dermatitis, cracked and sore lips, inflamed tongue, confusion, depression and insomnia
  • Good food sources include brewer’s yeast, bananas, cereal grains, legumes, vegetables (especially carrots, spinach and peas), potatoes, milk, cheese, eggs, fish and sunflower seeds
  • Folate, Folic Acid (Vitamin B9)
  • Works with B12 to form healthy red blood cells
  • Assists in forming DNAand RNA
  • Plays an extremely important role in preventing birth defects during early pregnancy (spina bifida)
  • Is found indark leafy greens (spinach, collard greens, romaine lettuce), citrus fruits (especially oranges), beans, peas, lentils, enriched pasta and breads
  • Vitamin B9 Deficiency

Signs and symptoms of B9 deficiency include:

  • Megaloblastic anemia (abnormal red blood cells)
  • Red, beefy tongue that can be painful
  • Angular stomatitis
  • Nausea, vomiting, abdominal pain, and diarrhea
  • Neurologic presentations (cognitive impairment, dementia, and depression)
  • Cobalamin, Cyanocobalamin (Vitamin B12)
  • Exists in several forms and contains the mineral cobalt
  • Compounds with vitamin B12 activity are collectively called ‘cobalamins’
  • Is required for proper red blood cell formation, neurological function, and DNA synthesis
  • NOTE: B12 is needed for folate metabolism!
  • Is only found in animal products (vegans can obtain B12 from sea vegetables and fortified soy milk)
  • Requires intrinsic factor in order to be absorbed(the body makes a special substance in the stomach known as the intrinsic factor)
  • NOTE: Dietary B12 is called extrinsic factor
  • Saliva Role indigestion and B12
  • Vitamin B12 Deficiency
  • Impaired intrinsic factor production can occur in adults due to autoimmune destruction of parietal cells
  • Gastrectomy(‘gastric bypass’) can also significantly reduce the production of intrinsic factor
  • May lead to nerve damage causing tingling and numbness in the hands and feet, muscle weakness, and loss of reflexes
  • If severe, can cause neurological problems such as confusion, dementia, depression, and memory loss
  • Can cause weakened bones
  • Can involve the digestive tract and include nausea, vomiting, heartburn, abdominal bloating and gas, constipation or diarrhea, loss of appetite, and weight loss
  • Can cause an enlarged liver
  • Can cause cutaneous manifestations of pallor and brown-gray fingernail and toenail discoloration
  • can cause pernicious anemia:
  • A form of megaloblastic anemia resulting from vitamin B12 deficiency due to lack of intrinsic factor
  • Often due to autoimmune disorder
  • Asmooth, thick, red tongue is a sign of vitamin B12 deficiency and pernicious anemia

BOARD ALERTS:

  • Know functions, sources and deficiencies of fat- and water-soluble vitamins
  • Know oral manifestations of deficiency states:
  • Friable tissue and gingival bleeding associated with vitamin C deficiency
  • Glossitis suggests cobalamin (B12) deficiency
  • Glossitis and cheilosis suggest pyridoxine (B6) deficiency
  • Gingivitis, stomatitis, and glossitis may indicate niacin (B3) deficiency

Review of Nutrient