Vitamins Flashcards
What are the fat-soluble vitamins?
A, D, E, and K.
How are fat-soluble vitamins stored in the body?
Fat-soluble vitamins are stored in the liver and adipose tissue. It takes longer to deplete stores of fat-soluble vitamins, which makes them accumulate and increasing risk for toxicity.
What are 2 forms of vitamin A and are both toxic when eaten in excess?
Retinoids (retinal, retinol, and retinoic acid): The chemical forms of preformed vitamin A. They assist in vision, growth, reproduction, immunity, and upkeep of epithelial tissue. This form is found in animal foods (liver, eggs, fish oil, dairy). Carotenoids: They’re precursors of vitamin A and are converted to retinoids by the body. They act as antioxidants (Anti-aging/cancer/atherosclerosis). Beta-carotenes in foods neutralize free radicals that can damage DNA. There are 50+, the strongest is beta-carotene. They give fruits and vegetables yellow, red, and orange color and are also found in green leafy veggies. Some food sources are apricots, sweet potato, carrots and spinach. Carotenoids are not toxic
What are some symptoms and diseases related to vitamin A deficiency?
Vitamin A is involved in perception of light in the eye: retinal+opsin=rhodopsin. Rhodopsin transfers light energy to the brain visual centers. Vitamin A deficiency thus results in night blindness and also prevents proper growth. Xerophthalmia: An irreversible blindness due to hardening of the cornea and drying of the mucous membranes of the eye. Deficiency of Vitamin A leads to deterioration of epithelial tissue such as the lining of the eye or skin. If not treated permanent blindness occurs.Hyperkeratosis: A condtion which makes the skin rough and bumpy, prevents proper sweating, and causes skin to be dry and thick. It can be reversed with vitamin A supplementation
What’s the difference between acute vitamin A toxicity and chronic vitamin A toxicity?
Acute toxicity occurs when a large amount of vitamin A is consumed, resulting in coma and death. Chronic toxicity occurs over a long period of time and cause liver damage, eye, skin, and bone problems. It can also cause birth defects or spontaneous abortion.
What is Hypercarotenemia?
High consumption of carotenoids results in the yellow or orange tinging of skin. It can be reversed with lessened intake.
What are Retin A and Acutane?
Retin A is an anti-wrinkle drug. Acutane is an anti-acne drug. Both can produce borderline vitamin A toxicity. Symptoms include dry mouth and eyes, changes in liver function, and greater blood lipid levels. Neither should be used before pregnancy in fear of causing birth defects
How is vitamin D like a hormone, but also like a vitamin?
Vitamin D is like a hormone because it’s made by the skin (w/sun) and so isn’t essential in the diet and it’s made in one organ but acts on and affects others. Vitamin D is also like a vitamin because if there’s not enough sun the skin can’t produce enough/any and thus it must be consumed instead
What are Ergocalciferol and Cholecalciferol?
Vitamin D2 and D3. D2 is found only in plant foods. D3 is found in animal foods and is produced in our skin when ultraviolet light reacts with 7 dehydrocholesterol.
What are some of the functions of vitamin D?
It facilitates the absorption of calcium and phosphorus and maintenance of bone. It also helps with cell differentiation
What is Rickets?
A vitamin D deficiency disease in children. Symptoms include deformities of the skeleton (bowed legs and knocked knees).
What is Osteomalacia?
A vitamin D deficiency disease in adults in which the bones become weak and prone to fractures.
What is the active form of vitamin E in our body and good food sources for it?
Tocopherols are the active form in our body. The most active natural form is d-alpha tocopherol. It’s found in nuts, plant/seed oil, leafy green veggies, avocados, and broccoli.
What are some of the functions of vitamin E?
It’s an antioxidant that protects unsaturated fats in cell membranes from damage by free radicals. It protects white blood cells, improves immune function, and increases absorption of vitamin A. It destroys free radicals when they first attack cells. It maintains red blood cells, nervous tissue cells, and immune system cells.
What are symptoms of vitamin E toxicity?
Inhibition of blood clotting, increased risk of stroke, and intestinal discomfort. Large doses interfere with vitamin K absorption which lessens blood’s ability to clot.
What are the 2 forms of vitamin K and how is it unique in comparison to other fat-soluble vitamins?
The 2 forms of vitamin K are Phylloquinone, the form found in plants (green leafy veggies, veggie oils, legumes) and the primary dietary form, and Menaquinone, the animal (fish oil, meat) form also produced by bacteria in the large intestine. Vitamin K isn’t stored in liver.
What is the primary function of vitamin K?
Vitamin K is a coagulant. That is to say, it helps the blood clot.
What are symptoms of vitamin K deficiency?
Abnormal blood clotting and easy bruising, most common in newborns and those taking antibiotics
Is vitamin K toxicity common?
No, it’s the result of supplement overuse. Symptoms include anemia and liver damage.
What are the water-soluble vitamins and how are they stored in body?
Water-soluble vitamins aren’t stored in the body, excess is excreted in the urine, so they must be consumed on a regular basis. They include the 8 B vitamins and vitamin C
What are the names of the 8 B vitamins?
Thiamin, Riboflavin, Niacin, Folate, B6, B12 (cobalamin), Biotin, and Pantothenic acid
What are some food sources of thiamin?
Thiamin is spread widely throughout foods such as fortified breads and cereals, pork, and whole grains. Due to its availability deficiency is rare.
What is Beriberi?
Beriberi: A disease caused by thiamin deficiency. The body’s inability to metabolize energy leads to muscle wasting and nerve damage. In later stages people may be unable to move. The heart muscle may also be affected, and thus there’s potential for fatal heart failure. Beriberi reflects thiamin’s role in glucose metabolism and acetylcholine synthesis. Symptoms include depression, weakness, poor coordination, nerve tingling, and heart changes. Advanced beriberi results in paralysis and death
What happens when riboflavin is exposed to light and what are some of its food sources?
When exposed to light the vitamin loses its activity. It’s found primarily in milk, but also green veggies and enriched grains
What is Ariboflavinosis?
A condition caused by riboflavin deficiency. Symptoms are sore throat, swelling of mucous membrane in the mouth and throat, dry and scaly lips, a purple-colored tongue, and inflamed irritated patches of skin. Severe deficiency can impair metabolism of vitamin B6 (pyridoxine) and niacin
What are some of the functions of niacin?
It’s a coenzyme in glycolysis, the electron transport chain, and and fat metabolism. It forms the coenzymes nicotinamide adenine dinucleotide (NAD) and nicotinamide adenine dinucleotide phosphate (NADHP). It also acts as a coenzyme in DNA replication/repair and in the process of cell differentiation. It’s also important to carbohydrate, fat, and protein metabolism and synthesis of fatty acids and sterols
What is “niacin flush”?
Flushing caused by dilation of blood vessels, also accompanied by nausea, diarrhea, rash, heartburn, and liver/heart abnormalities caused by niacin toxicity
What is Pellagra?
Pellagra causes irritability, insomnia, and sore tongue due to niacin deficiency. Severe pellagra results in Diarrhea, Dementia, Dermatitis, and Death (4 D’s). It’s associated with a corn-based diet and is still common in India, China, and Africa. Corn treated with alkaline makes niacin more available for digestion.
What are some functions of B6 (pyridoxine)?
It’s an important coenzyme in metabolism (especially protein metabolism) and neurotransmitter and hemoglobin synthesis. It’s also needed in homocysteine conversion
What are symptoms of B6 deficiency?
Headache, sore tongue, nausea, vomiting, nerve changes, and anemia.
How toxic is B6?
Caused by over supplementation, vitamin B6 is extremely toxic. Toxicity symptoms include tingling in limbs, which leads to permanent nerve and neurological damage
What are good food sources of folate?
It’s found in green leafy veggies, oranges, and legumes
What are some of folate’s functions?
It acts as coenzymes in transfer of single carbon molecules, is needed for synthesis of DNA and RNA, needed for amino acid metabolism, and works with B12.
What are some symptoms of folate deficiency?
Megaloblastic or macrocytic anemia, neural tube defects in infants, and high levels homocysteine (increase risk of heart disease)
What are neural tube defects?
The most common malformations of the central nervous system that occur during fetal development. Defects can range from protrusion of the spinal cord outside the vertebral column to absences of brain tissue. Some are minor and can be surgically corrected; others result in paralysis and some in death
What is macrocytic anemia?
A form of anemia manifested as the production of larger than normal red blood cells containing insufficient hemoglobin, which inibits adequate transport of oxygen; also called megaloblastic anemia. Symptoms are weakness, fatigue, difficulty concentrating, irritability, headache, shortness of breath, and reduced exercise tolerance.
What foods is vitamin B12 found in and how is different from other water-soluble vitamins?
It’s only found in animal foods. It requires intrinsic factor (secreted from parietal cells of the stomach) for absorption from the intestinal tract. It’s stored in the liver, unlike other water-soluble vitamins.
What are the functions of vitamin B12?
It’s a coenzyme in folate metabolism and nerve function. It rearranges carbon atoms and helps breakdown of fatty acids as citric acid. It also helps in homocysteine metabolism
What are symptoms of B12 deficiency?
Pernicious anemia, macrocytic anemia, and poor nerve function. Deficiency of B12 results in deficiency of folate which causes megaloblastic/macrocytic anemia. Deficiency of only B12 results in pernicious anemia. If untreated can lead to permanent nerve and neurological damage. However deficiency is rare.
What is pernicious anemia?
This anemia occurs at the end stage of an autoimmune disorder that causes loss of cells in the stomach. Symptoms include pale skin, reduced energy and exercise tolerance, fatigue, and shortness of breath. Nerve cells are also destroyed, resulting in loss of coordination. Central nervous system involvement can lead to irritability, confusion, depression, and even paranoia.
What foods is vitamin C found in, is it stable or unstable?
It’s found in citrus fruits, strawberries, and cantaloupe. It’s very unstable, rapidly destroyed by oxygen, sensitive to light, high temperature, copper, and low acid conditions.
What are the functions of vitamin C?
It’s important in hydrogen transport, collagen formation, and wound healing. It act as an antioxidant, increases iron absorption, regenerates vitamin E, and may lessen the severity of colds.
Vitamin C toxicity results in what?
Diarrhea
What is Scurvy?
A disease caused by vitamin C deficiency. Symptoms include bleeding gums, easy bruising, and slow wound healing. It occurs with low intake and as Rebound Scurvy, when a person stops consuming high amounts of vitamin C
