Nutrition, Ch. 8 (Vitamins)

3 Names for Vitamin A
Different chemical forms... Retinol, Retinal, Retinoic acid (think: retina)
Precursor to Vitamin A
Beta Carotene, found in carrots, helps eyesight (also an important anti-oxidant)
Functions of Vitamin A
Visual pigments (helps you see in bright light, dim light, colors)
Important component of mucopolysaccharides (helps maintain the integrity mucous membranes); also: roles in gene expression, cell differentiation, immunity, and reproduction & growth.
What enhances absorption of Vitamin A?
Vitamin E
What reduces absorption of Vitamin A?
Mineral oil (dangerous to use more than one dose every few days -- interferes with vitamin absorption in the intestine)
Beri beri
CANNOT MOVE, CANNOT MOVE... a nervous system ailment caused by a deficiency of thiamin (vitamin B1) in the diet. Thiamin is involved in the breakdown of energy molecules such as glucose and is also found on the membranes of neurons. Symptoms of beriberi include severe lethargy and fatigue, together with complications affecting the cardiovascular, nervous, muscular, and gastrointestinal system
a condition caused by deficiency of ascorbic acid (vitamin C)
Two main classifications of vitamins
Fat-soluble (stored in body, can become toxic, no need to take every day) and water-soluble (not stored, can become deficient, take daily)
What are the four fat-soluble vitamins?
Vitamins A, D, E, K
inactive chemical substance related to a vitamin that will be converted to the vitamin once ingested (and activated); also called provitamins
epithelial cells
cells that cover body surfaces: outside the body is the skin and inside the body they form linings for the organs; surface epithelial cells in these linings form a smooth surface by secreting smooth, slippery mucous
Food sources of Vitamin A or Beta Carotene
Fish liver oil ("pure" A: clear) or oily fish (salmon, mackerel)
Fortified milk ("pure" A: clear)
Dark yellow vegetables
Dark green vegetables
Signs of Vitamin A Deficiency
Night blindness (difficult to see during changes in light)
Keratinization of epithelial cells (dry inside nose/mouth, ulcers)
Some infectious diseases
accumulation of keratin (normal protein of hair & nails) in tissues due to low mucous membrane integrity from vit. A deficiency; example: xerophthalmia (drying of the cornea) whose last stage is keratomalacia (total blindess)
Signs of Vitamin A Toxicity
6700 IU - the daily tolerable Upper Intake Level
Scaly dermatitis (some dermatologists used Retin-A as a treatment for acne BUT it also changed bone structure: thickened, difficult to heal if broken)
Bone changes, teratogenic risk (birth defects), liver abnormalities
Names for Vitamin D
"Sunshine" vitamin
What vitamin MAY be reclassified as a hormone?
Vitamin D
Precursor for vitamin D
7 Dehydrocholesterol (on skin, converted to D by sunshine - UNLESS you are wearing sunscreen)
vitamin treatment for diabetes
intramuscular injection of D (80% of diabetics are deficient in vitamin D)
Functions of vitamin D
Facilitates absorption and utilization of calcium and phosphorus (for bone growth & maintenance); as a hormone targeting the small intestine, the kidneys and the bones); perhaps regulation of the immune system
Main food source of vitamin D
Fortified milk (yoplait and dannon are the only yogurts that are fortified; most cheese is NOT)
Signs of Vitamin D Deficiency
SAME as calcium deficiency: such as rickets (bowed legs) or its adult form: osteomalacia (softening of the bones); also a risk factor in osteoporosis (reduced bone density)
Signs of Vitamin D Toxicity
2000 IU is the daily tolerable Upper Intake Level
Calculi (kidney stones)
Calcification of soft tissue
Weight loss
Polyurea (frequent urination)
Another Name for Vitamin E
Functions of Vitamin E
Antioxidant, especially in lungs ("Fountain of Youth" vitamin; used in early treatment of burns); may also prevent oxidation of LDL, which can lead to atherosclerosis
Cellular respiration
What helps the absorption of vitamin E?
Food sources of vitamin E?
Vegetable oils (and products made from them)
Sunflower seeds, Almonds
Another name for Vitamin K
Quinone (K stands for the Danish word "koagulation," meaning "clotting")
Functions of Vitamin K
Coagulation of blood (if you are on coumadin, you should eat vitamin K daily and in consistent quantities)...Prothrombin, Factors VII, IX, X (clotting factors in blood)
Also helps keep bones strong and dense.
Synthesized by intestinal bacteria (antibiotics can interfere)
Food sources of Vitamin K
Green leafy vegetables
Egg yolk
Soybean oil
Signs (and causes) of Vitamin K Deficiency
Prolonged clotting time... caused by:
Sterile intestine in newborn
Long term antibiotic therapy
Anticoagulant therapy
Vitamin K Toxicity
NEVER from natural Vitamin K
Menadione: synthetic vitamin K, can be toxic
What are the two main types of water-soluble vitamins?
B vitamins and Vitamin C
List the B vitamins
Thiamin, Riboflavin, Niacin, Pantothenic acid, Biotin, Vitamin B6, Folate, Vitamin B12
causing abnormal fetal development and birth defects
How much exposure to the sun will provide enough Vitamin D?
With clear summer days, exposing hands face and arms: 10 minutes per day several times a week; longer for darker-skinned people (6x longer?)
Why do AIs for Vitamin D increase with age?
The older someone gets, the less exposure you have to sunlight and the less efficient your body is at activating D.
What "mythic" properies of Vitamin E are NOT true?
Vitamin E DOES NOT improve athletic skill, enhance sexual performance, cure sexual dysfunction, prevent or cure muscular dystrophy, slow or prevent aging (graying of hair, wrinkling of skin, slowing of body organs)
Signs of Vitamin E deficiency
Loss of muscle coordination & reflexes resulting in impaired movement, vision & speech; also: erythrocyte hemolysis, where red blood cells break apart (often found in premature infants born before Mom transferred her Vitamin E)
Signs of Vitamin E toxicity
Not as common or as known as with A & D; VERY high doses can interfere with blood-clotting.
Why should you avoid vitamin C supplements that spend a lot of time in your mouth?
Vitamin C will eat the enamel off your teeth?
Another name for Vitamin C?
Ascorbic Acid
Functions of Vitamin C?
Collagen - helps bind cells together (e.g. prevents bruising)
Dentin - tooth layer that keeps teeth strong (e.g. sailors had broken teeth)
Helps convert Ferric iron into Ferrous iron (usable by body)
Helps convert Folic acid (B vit) into Folinic (usable by body)
Necessary to make adrenal (sex) steroids from cholesterol
Major tissue composing teeth, covered by the enamel in the crown and a protective layer of cementum in the root
Sources of Vitamin C?
Green (and Red!) pepper
Raw cabbage (not cooked) or Sauerkraut or Coleslaw or Kim Chee
Most should be uncooked
What is the relationship between Vitamin C and stress?
When the body is stressed, adrenal glads release large amounts of vitamin C together with the stress hormones (thus, stress increases the need for C somewhat)
Signs of Vitamin C deficiency
Progressive symptoms: one thick curly dark hair growing in an unusual place on the body
Too much Vitamin C
can change the pH of urine: burning sensation (daily supplements are not recommended -- rather take every three days with best meal of the day, one with protein)
What is the name of Vitamin B-1
Functions of Thiamin
Complete oxidation of CHO (release of energy in Krebs cycle)
Sources of Thiamin
Whole grain (remember: discovered in rice bran)
Enriched products
What is enrichment?
replacing nutrients (such as thiamin) that were lost in processing; examples include: white flour
What are the enrichment nutrients?
thiamin, riboflavin, niacin, iron and sometimes folic acid (in a very stable form: nutrient content does not degrade as quickly as "natural" foods)
Where should you store whole grain bread?
Freezer (keeps nutrient content from degrading)
What does irradiation do to thiamin?
It breaks it down
Thiamin Deficiency
Beri Beri: affects nervous system (see previous note)
An enzyme which digests thiamin, found in RAW fish and seafood (deactivated by cooking)
Sushi - any thiamin consumed will not be utilized)
Function of Riboflavin
Release of energy from cell mitochondria
What is the name of vitamin B-2
Sources of riboflavin
Cheddar cheese
Cottage cheese
Enriched products
What breaks down riboflavin
sunlight or fluorescent lighting decreases availability
Riboflavin deficiency
Cheilosis (symptoms: dry lips, dry nares, etc.)
What is another name for niacin?
Nicotinic Acid
What is the precursor to Niacin
Tryptophan (added to thiamin, riboflavin & pyridoxine, makes niacin)
Functions of Niacin
Release of energy
Synthesis of Protein, Fat, and Pentoses (used to treat dyslipidemia: can bring HDL, LDL into the right ranges but causes flushing or hot flashes AND increases in blood sugar)
Sources of Niacin
Niacin Deficiency
Pellegra: (1) dermititis; (2) diarrhea; (3) dementia; (4) death over six months
What is the name for Vitamin B-6?
Functions of pyridoxine (B-6)
Coenzyme necessary for Transamination (proteins)
Also helps turn Tryptophan into niacin
Used in production of Antibodies
Pyridoxine deficiency
microcytic hypochronic anemia (small pink cells) and, for women taking oral contraceptives: urinary tract calculi (kidney stones). Yaz can cause excretion of B-6...
Sources of pyridoxine
Muscle meats
Green vegetables
Egg yolk
Wheat germ
Folic acid deficiency
Anemia: macro ovalocytic anemia (very large blood cells) -- because there are fewer cells they need to be larger
Spina bifida (folic acid has been added to grains)
Glossitis (inflammation of the tongue)
Can be caused by: Oral contraceptives, Alcohol, Alkaline GI tract ANTACIDS, gastric bypass or banding
What is the chemical name for folic acid?
Functions of folic acid
Heme (blood) functions
Important in formation of Red blood cells
Coenzyme in synthesis
Formation of neural tubes (beginnings of neural system)
Sources of folic acid
Kidney beans
Lima beans
Whole wheat
Dried beans
Enriched products
Danger of too much folic acid?
Folic Acid above normal intake can mask Vitamin B12 deficiency
Another name for Vitamin B-12
Functions of B-12
Normal growth, formation of nervous tissue
Blood formation
What is necessary for absorption of B-12
Intrinsic Factor (made in the stomach)
Lack of Intrinsic Factor (often a symptom of older age) can lead to: Pernicious anemia
Sources of B-12
Foods of animal origin
Wheat germ (small amounts)
Brewer's yeast (or is it an animal?)
(vegan diet can lead to growth problems, memory problems)
Functions of Pantothenic Acid
Necessary to make Coenzyme A (used in Krebs cycle)
Fat and cholesterol synthesis
Glucose carrier system (through intestinal wall into blood)
Sources of Pantothenic Acid (it's everywhere!)
All animal and plant foods
Deficiency in Pantothenic Acid
Not seen in humans
May be loss of antibody production when there is not enough Pantothenic Acid present (created experimentally)
Functions of Biotin
Synthesis and oxidation of fatty acids
Deamination of proteins
Good for nails and hair
Biotin deficiency
Symptoms include glossitis (inflamed & sore tongue - can affect speech) Avidin, in raw egg whites, reduces biotin absorption (Sylvester Stallone in Rocky)
Some chemotherapy can also result in biotin deficiency
Sources of biotin
intestinal synthesis (from bacteria) and food:
Egg yolk
Fruits (Banana, Watermelon, Grapefruit, Strawberry)
List some examples of epithelial tissue INSIDE the body
Lining of the mouth, stomach & intestines;
Lining of the lungs and the passages leading to them;
Lining of the bladder;
Lining of the uterus and the vagina;
Lining of the eyelids and sinus passageways
What is the difference between fortification and enrichment?
Enrichment is replacing nutrients that were lost in processing; fortification is adding nutrients to foods that were not originally found in those foods (such as vitamin D in milk)