VITAMIN

Vitamins are organic compounds that are essential in very small amounts for supporting normal physiologic function. We need vitamins in our diet because our bodies can’t synthesize them quickly enough to meet our daily needs.

Vitamins have three characteristics:

• They are natural components of foods; usually present in very small amounts.
• They are essential for normal physiologic function (eg. growth, reproduction, etc).
• When absent from the diet, they will cause a specific deficiency.

Vitamins are generally categorized into the following types

1. Water-soluble
2. Fat-soluble

Water-soluble vitamins

Vitamin B1 (Thiamine)

• Deficiency: Symptoms include burning feet, weakness in extremities, rapid heart rate, swelling, anorexia, nausea, fatigue, and gastrointestinal problems.
• BENEFITS: Helps convert food into energy. Needed for healthy skin, hair, muscles, and brain and is critical for nerve function.
• Toxicity: None knew.
• Sources: Sunflower seeds, asparagus, lettuce, mushrooms, black beans, navy beans, lentils, spinach, peas, pinto beans, lima beans, eggplant, Brussels sprouts, tomatoes, tuna, whole wheat, soybeans

Vitamin B2 (Riboflavin)

• Deficiency: Symptoms include cracks, fissures and sores at the corner of mouth and lips, dermatitis, conjunctivitis, photophobia, glossitis of tongue, anxiety, loss of appetite, and fatigue.
• BENEFITS: Helps convert food into energy. Needed for healthy skin, hair, blood, and brain
• Toxicity: Excess riboflavin may increase the risk of DNA strand breaks in the presence of chromium. High-dose riboflavin therapy will intensify urine color to a bright yellow (flavinuria) – but this is harmless.
• Sources: Almonds, soybeans/tempeh, mushrooms, spinach, whole wheat, yogurt, mackerel, eggs, liver

Vitamin B3 (Niacin)

• Deficiency: Symptoms include dermatitis, diarrhea, dementia, and stomatitis.
• BENEFITS: Helps convert food into energy. Essential for healthy skin, blood cells, brain, and nervous system.
• Toxicity: Niacin from foods is not known to cause adverse effects. Supplemental nicotinic acid may cause flushing of the skin, itching, impaired glucose tolerance, and gastrointestinal upset. Intake of 750 mg per day for less than 3 months can cause liver cell damage. High dose nicotinamide can cause nausea and liver toxicity.
• Sources: Mushrooms, asparagus, peanuts, brown rice, corn, green leafy vegetables, sweet potato, potato, lentil, barley, carrots, almonds, celery, turnips, peaches, chicken meat, tuna, salmon

Vitamin B5 (Pantothenic acid)

• Deficiency: Very unlikely. Only in severe malnutrition may one notice the tingling of feet.
• BENEFITS: Helps convert food into energy. Help make lipids (fats), neurotransmitters, steroid hormones, and hemoglobin.
• Toxicity: Nausea, heartburn, and diarrhea may be noticed with high dose supplements.
• Sources: Broccoli, lentils, split peas, avocado, whole wheat, mushrooms, sweet potato, sunflower seeds, cauliflower, green leafy vegetables, eggs, squash, strawberries, liver

Vitamin B6 (Pyridoxine)

• Deficiency: Symptoms include chelosis, glossitis, stomatitis, dermatitis (all similar to vitamin B2 deficiency), nervous system disorders, sleeplessness, confusion, nervousness, depression, irritability, interference with nerves that supply muscles and difficulties in movement of these muscles, and anemia. Prenatal deprivation results in mental retardation and blood disorders for the newborn.
• BENEFITS: Aids in lowering homocysteine levels and may reduce the risk of heart disease helps convert tryptophan to niacin and serotonin, a neurotransmitter that plays key roles in sleep, appetite, and moods. Help make red blood cells Influence cognitive abilities and immune function.
• Toxicity: High doses of supplemental vitamin B6 may result in painful neurological symptoms.
• Sources: Whole wheat, brown rice, green leafy vegetables, sunflower seeds, potato, garbanzo beans, banana, trout, spinach, tomatoes, avocado, walnuts, peanut butter, tuna, salmon, lima beans, bell peppers, chicken meat

Vitamin B7 (Biotin)

• Deficiency: Very rare in humans. Keep in mind that consuming raw egg whites over a long period of time can cause biotin deficiency. Egg whites contain the protein avidin, which binds to biotin and prevents its absorption.
• BENEFITS: Helps convert food into energy and synthesize glucose. Help make and break down some fatty acids. Needed for healthy bones and hair.
• Toxicity: Not known to be toxic.
• Sources: Green leafy vegetables, most nuts, whole-grain bread, avocado, raspberries, cauliflower, carrots, papaya, banana, salmon, eggs

Vitamin B9 (Folic acid)

Folate is the naturally occurring form found in foods. Folic acid is the synthetic form used in commercially available supplements and fortified foods. Inadequate folate status is associated with neural tube defects and some cancers.

• Deficiency: One may notice anemia (macrocytic/megaloblastic), sprue, Leukopenia, thrombocytopenia, weakness, weight loss, cracking and redness of tongue and mouth, and diarrhea. In pregnancy, there is a risk of low birth weight and preterm delivery.
• BENEFITS:
• Toxicity: None of the food. Keep in mind that vitamin B12 and folic acid deficiency can both result in megaloblastic anemia. Large doses of folic acid given to an individual with an undiagnosed vitamin B12 deficiency could correct megaloblastic anemia without correcting the underlying vitamin B12 deficiency.
• Sources: Green leafy vegetables, asparagus, broccoli, Brussels sprouts, citrus fruits, black-eyed peas, spinach, great northern beans, whole grains, baked beans, green peas, avocado, peanuts, lettuce, tomato juice, banana, papaya, organ meats

Vitamin B12 (Cobalamin)

Vitamin B12 must combine with intrinsic factor before it’s absorbed into the bloodstream. We can store a year’s worth of this vitamin – but it should still be consumed regularly. B12 is a product of bacterial fermentation, which is why it’s not present in higher-order plant foods.

• Deficiency: Symptoms include pernicious anemia, neurological problems, and sprue.
• BENEFITS: Aids in lowering homocysteine levels and may lower the risk of heart disease. Assists in making new cells and breaking down some fatty acids and amino acids. Protects nerve cells and encourages their normal growth Helps make red blood cells and DNA.
• Toxicity: None known from supplements or food. Only a small amount is absorbed via the oral route, thus the potential for toxicity is low.
• Sources: Fortified cereals, liver, trout, salmon, tuna, haddock, egg

Vitamin C (Ascorbic acid)

• Deficiency: Symptoms include bruising, gum infections, lethargy, dental cavities, tissue swelling, dry hair and skin, bleeding gums, dry eyes, hair loss, joint paint, pitting edema, anemia, delayed wound healing, and bone fragility. Long-term deficiency results in scurvy.
• BENEFITS: Foods rich in vitamin C may lower the risk for some cancers, including those of the mouth, esophagus, stomach, and breast. Long-term use of supplemental vitamin C may protect against cataracts. It helps make collagen, a connective tissue that knits together wounds and supports blood vessel walls. Help make the neurotransmitters serotonin and norepinephrine Acts as an antioxidant, neutralizing unstable molecules that can damage cells. Bolsters the immune system.
• Toxicity: Possible problems with very large vitamin C doses including kidney stones, rebound scurvy, increased oxidative stress, excess iron absorption, vitamin B12 deficiency, and erosion of dental enamel. Up to 10 grams/day is safe based on most data. 2 grams or more per day can cause diarrhea.
• Sources: Guava, bell pepper, kiwi, orange, grapefruit, strawberries, Brussels sprouts, cantaloupe, papaya, broccoli, sweet potato, pineapple, cauliflower, kale, lemon juice, parsley.

Fat-soluble vitamins

Vitamin A (Retinoids)

Carotenoids that can be converted by the body into retinol are referred to as provitamin A carotenoids.

• Deficiency: One may notice difficulty seeing in dim light and rough/dry skin.
• BENEFITS: Essential for vision Lycopene may lower prostate cancer risk. Keeps tissues and skin healthy. Plays an important role in bone growth and in the immune system. Diets rich in the carotenoids alpha-carotene and lycopene seem to lower lung cancer risk. Carotenoids act as antioxidants. Foods rich in the carotenoids lutein and zeaxanthin may protect against cataracts
• Toxicity: Hypervitaminosis A is caused by consuming excessive amounts of preformed vitamin A, not the plant carotenoids. Preformed vitamin A is rapidly absorbed and slowly cleared from the body. Nausea, headache, fatigue, loss of appetite, dizziness, and dry skin can result. Excess intake while pregnant can cause birth defects.
• Sources: Carrots, sweet potato, pumpkin, green leafy vegetables, squash, cantaloupe, bell pepper, Chinese cabbage, beef, eggs, peaches

Vitamin D (Calciferol, 1,25-dihydroxy vitamin D)

Cholecalciferol = vitamin D3 = animal version; ergocalciferol = vitamin D2 = plant version

• Deficiency: In children, vitamin D deficiency can result in rickets, deformed bones, retarded growth, and soft teeth. In adults, vitamin D deficiency can result in osteomalacia, softened bones, spontaneous fractures, and tooth decay. Those at risk for deficiency include infants, elderly, dark-skinned individuals, those with minimal sun exposure, fat malabsorption syndromes, inflammatory bowel diseases, kidney failure, and seizure disorders.
• BENEFITS: Helps maintain normal blood levels of calcium and phosphorus, which strengthens bones. It helps form teeth and bones. Supplements can reduce the number of non-spinal fractures
• Toxicity: Hypervitaminosis D is not a result of sun exposure but from chronic supplementation. Excessive supplement use will elevate blood calcium levels and cause loss of appetite, nausea, vomiting, excessive thirst, excessive urination, itching, muscle weakness, joint pain, and disorientation. Calcification of soft tissues can also occur.
• Sources: Sunlight, fortified foods, mushrooms, salmon, mackerel, sardines, tuna, eggs

Vitamin E (tocopherol)

• Deficiency: Only noticed in those with severe malnutrition. However, suboptimal intake of vitamin E is relatively common.
• BENEFITS: Acts as an antioxidant, neutralizing unstable molecule that can damage cells. Protects vitamin A and certain lipids from damage. Diets rich in vitamin E may help prevent Alzheimer's disease.
• Toxicity: Minimal side effects have been noted in adults taking supplements in doses less than 2000 mg/day. There is a potential for impaired blood clotting. Infants are more vulnerable.
• Sources: Green leafy vegetables, almonds, sunflower seeds, olives, blueberries, most nuts, most seeds, tomatoes, avocado

Vitamin K

• Deficiency: Tendency to bleed or hemorrhage and anemia.
• BENEFITS: Activates proteins and calcium essential to blood clotting. May help prevent hip fractures
• Toxicity: May interfere with glutathione. No known toxicity with high doses.
• Sources: Broccoli, green leafy vegetables, parsley, watercress, asparagus, Brussels sprouts, green beans, green peas, carrots