HUN 2201 Chapter 7-9

vitamin B12 absorption

1. Vitamin B12 in food is bound to protein 2. Stomach- acid and pepsin help release Vitamin B12 from food proteins 3. Cells in the stomach lining release intrinsic factor (IF). 4. In the upper portion of the small intestine (duodenum), intrinsic factor binds to vitamin B12. 5. In the lower part of the small intestine (ileum), the vitamin B12-intrinsic factor complex binds to receptors on cells, allowing absorption. 6. In the colon, vitamin B12 is synthesized by microorganisms but cannot be absorbed.

A food item labeled as sodium free means that is contains _____ mg of sodium per serving? .5 0 <5

<5

Provitamin or Vitamin precursor

A compound that can be converted into the active form of a vitamin in the body.

Beri-beri is a disease associated with which water soluble vitamin? B12 B6 B1

B1

Vitamin A

Beta-carotene: precursor converted into vitamin A Functions: Vision Retina: conversion of light energy into nerve impulses Maintenance of clear cornea Participates in protein synthesis & cell differentiation, thereby maintaining health of epithelial [cells open to outside of body] tissues including skin Supports reproduction & growth Sources: Animal forms (retinol): Naturally occurring food sources: Liver (limit: very high, 1 oz has 3 x the RDA) This source of Vitamin A should be limited for pregnant woman. An excessive intake of liver during pregnancy may cause birth defects. fish liver oils [too high, don't use], milk fat (butter, cream, whole milk & cheese), eggs Fortified products: skim/low fat milk margarine Plant forms (carotenoids; greatest Vit A activity is beta-carotene - deep yellow-orange): Dark green leafy: spinach, broccoli, romaine lettuce, collard/turnip/mustard greens (deep yellow-orange of carotene obscured by green of chlorophyll) Deep yellow-orange vegetables & fruits: cantaloupe, carrots, sweet potatoes, pumpkin, apricots winter squash (butternut, acorn) [Plant forms are absorbed best when there is fat at the meal; low fat salad dressing is better than fat-free to help absorb beta-carotene] Very low fat diets [<10g/d] risk malabsorption (lesser sources) Reddish: tomato juice, watermelon RDA: Men 900 µg/d, Women 700 µg/d Daily Value (DV): 1500 µg/d (=5000 IU) [conversion ~3.3] Retinol activity equivalent(RAE): amount of retinol, or carotenoids that have Vit A activity = 1 µg retinol Deficiency disease: Hypovitaminosis A Deficiency symptoms: Vision: night blindness (lack at retina, back of eye) => corneal drying (xerosis) => softening of cornea (keratomalacia) => corneal degeneration/blindness (xerophthalmia ) [lack at front of eye, cornea] Impaired immunity: world-wide deficiencies increase mortality (death). In populations with high levels of malnutrition and a lack of adequate healthcare, mortality from measles can be as high as 10%. Keratinization: epithelial cells not supported secrete hard protein keratin(like fingernails); especially problem in GI tract

Biotin is a vitamin that encourages hair growth. True False

False

There are no known potentially harmful side effects from taking herbal and nutrient supplements. True False

False

10. Explain the roles of vitamin A in keeping eyes healthy.

Functions: Vision Retina: conversion of light energy into nerve impulses Maintenance of clear cornea The visual cycle: 1. After entering the eye, light strikes the visual pigment rhodopsin, which is in the retina. Rhodopsin consists of the protein opsin combined with retinal. 2. The light causes the retinal molecule to change from a bent (cis) to a straight (trans) configuration. 3. A nerve signal is sent to the brain, telling us that there is light, and retinal is released from opsin. 4. Some retinal is lost from the cycle. 5. Some retinal returns to its original cis configuration and binds opsin to begin the cycle again. 6. When vitamin A is deficient the regeneration of rhodopsin is delayed. Until it is reformed, light cannot be perceived. 7. When vitamin A status is normal, vitamin A from the blood replaces any retinal lost from the cycle.

A disease that results in the diarrhea, dermatitis, and dementia is known as ____. Beriberi Pellagra Wernicke-Korsakoff

Pellagra

12. Describe the function of vitamin E.

Primary defender against adverse effects of free radicals Main action: stops chain reaction of free radicals producing more free radicals Protects cell membranes by preventing oxidation of PUFA Also protects Vitamin A (and precursor beta-carotene)

Calcium absorption would be the most difficult from which food? spinach canned salmon w/bones yogurt

Spanish

6. Explain why vitamin B6 is different than the other water-sol vitamins.

Stored: unlike other B-vitamins, can be stored in muscles (and turns over slowly)

1. Define Vitamin & Micronutrient

Vitamins are organic compounds that are essential in small amounts in the diet to promote and regulate body processes necessary for growth, reproduction, and the maintenance of health. When a vitamin is lacking in the diet, deficiency symptoms occur. When the vitamin is restored to the diet, the symptoms resolve. Structure: vitamins are individual units. Not linked together like glucose units in starch or amino acids in proteins. Function: They assist the enzymes that release the energy from carbohydrates, fats and proteins No usable energy is produced from the breakdown of a vitamin itself (micronutrients are non-energy containing molecules) Required amounts measured in: Milligrams (mg) [1000 mg = 1 gram] Micrograms (µg) [1000 µg = 1 mg]

2 Types of Vitamins

Water-soluble: Found in watery parts of foods Can move directly into the blood stream after absorption Circulate freely in watery cells Not stored in the body (except for B6) Fat-soluble: Found in the fatty parts of food Need to first enter the lymph before they can move into the blood stream Many require lipoproteins to move through the blood Can be stored in fatty tissue and liver

One main function of vitamin C is to... decrease absorption of iron prevent the common cold aid in collegen synthesis

aid in collegen synthesis

Riley previously overate and was mostly sedentary. She recently established a good eating pattern and has begun to walk regularly. Riley has demonstrated: weight management behavior modification weight loss

behavior modification

Sarah is lactose intolerant and is concern with her calcium intake. In order for her to get adequate calcium in her diet you recommend for her to eat... 1% milk apples canned sardines

canned sardines

Which of the following foods would contain the most beta-carotene? beef liver collard-greens whole milk

collard-greens

Energy in = Energy out is: energy deficit energy surplus energy balance

energy balance

A person who lacks ________ will likely become deficient in B12. intrinsic factor lipases amylases

intrinsic factor

Regulation of fluid and electrolyte balance depends primarily on the: kidneys intestines liver sweat glands

kidneys

Natural cheese has _________ processed cheese. less sodium than about the same amount of sodium as more sodium than

less sodium than

Non-heme iron absorption is enhanced by all the following EXCEPT: Vitamin C MFP (meat-fish-poultry) factor phytates

phytates

Jill exercises regularly and eats well, yet she cannot lose weight. Her body stays at 150 lbs despite her efforts. This is likely due to her being at her: set point BMR BMI

set point

Which of the following foods would provide the most amount of riboflavin? apple whole-wheat bread skim-milk

skim-milk

17. Define phytochemical

that inhibits the absorption of some nutrients.

Vitamin D is the only vitamin that humans can synthesize from ______. food gut microbiome ultra violet light

ultra violet light

Allison is 23 years old and is concerned about her weight, her BMI is 18.4, she is considered overweight underweight normal weight

underweight

13. Discuss how vitamin K is involved in blood clotting.

Blood is a fluid that flows easily through your blood vessels, but when you cut yourself, blood must solidify or clot to stop your bleeding. Vitamin K is a fat-soluble vitamin that is essential for the production of several blood proteins, called clotting factors, that are needed for blood to clot Vitamin K and blood clottingBlood clotting requires a series of reactions that result in the formation of a fibrous protein called fibrin. Fibrin fibers form a net that traps platelets and blood cells and forms the structure of a blood clot. Several of the clotting factors, including prothrombin, require vitamin K for synthesis. If vitamin K is deficient, they are not made correctly, and the blood will not clot.

8. Describe general deficiency and toxicity symptoms and conditions.

Check each Vitamin or chart in the book

Because of the high mineral and fiber content, a diet high in _________ is known to decrease the risk of high blood pressure. bread and pasta fish fruits and vegetables

fruits and vegetables

It is noon and Tim is really hungry for lunch, this hunger is triggered by which hormone? leptin ghrelin insulin

ghrelin

Which of the following minerals could cause liver toxicity when accumulated in excess in the body? potassium iron sodium

iron

Women who are pregnant or are of child-bearing age should consume folic acid to prevent _____. neural tube defects bone density loss diarrhea

neural tube defects

Which of the following minerals is found in high amounts in fruits and vegetables? potassium zinc selenium

potassium Regulation of fluid and electrolyte balance depends primarily on the: kidneys intestines liver sweat glands

Which of the following weight loss interventions would be considered the most invasive? weight loss drugs gastric bypass weight loss diet plan

gastric bypass

Niacin

is a B vitamin that forms coenzymes essential for glucose metabolism and the synthesis of fatty acids and cholesterol. The need for this water-soluble vitamin is so widespread in metabolism that a deficiency causes major changes throughout the body. The early symptoms of pellagra include fatigue, decreased appetite, and indigestion. These are followed by symptoms that can be remembered as the three Ds: dermatitis, diarrhea, and dementia. If left untreated, niacin deficiency results in a fourth D—death. Meats and grains are good sources of niacin. Niacin can also be synthesized in the body from the essential amino acid tryptophan Tryptophan, however, is used to make niacin only if enough of it is available to first meet the needs of protein synthesis. When the diet is low in tryptophan, it is not used to synthesize niacin. Because some of the requirement for niacin can be met through the synthesis of niacin from tryptophan, the RDA is expressed as niacin equivalents (NEs). One NE is equal to 1 mg of niacin or 60 mg of tryptophan, the amount needed to make 1 mg of niacin. niacin supplements can be toxic. Excess niacin supplementation can cause flushing of the skin, a tingling sensation in the hands and feet, a red skin rash, nausea, vomiting, diarrhea, high blood sugar levels, abnormalities in liver function, and blurred vision. The UL for adults is 35 mg/day from fortified foods and supplements. Doses of 50 mg/day or greater of one form of niacin are used as a drug to treat elevated blood cholesterol; this amount should be consumed only when prescribed by a physician.

The weight status of someone who typically binge eats is _________, while the weight status of someone who suffers from anorexia nervosa is ___________. underweight, overweight overweight, underweight normal weight, underweight

overweight, underweight

Most of the salt that Americans eat comes from... salt shaker at the table processed food home cooking

processed food

4. Explain the function of coenzymes.

Coenzyme: assists an enzyme to release energy (kcal) from CHO/fat/pro Many of the B-vitamins form part of these coenzymes The vitamin portion of a coenzyme allows a chemical reaction to occur; the rest of the coenzyme binds to the enzyme Without the coenzyme, the enzyme cannot function and energy (kcal) is not available in the body So vitamins are very important for assisting in the metabolism of the macronutrients Coenzymes are needed for enzyme activity. They act as carriers of electrons, atoms, or chemical groups that participate in the reaction. All the B vitamins as well as vitamins C and K are coenzymes; there are also coenzymes that are not dietary essentials and therefore are not vitamins.

16. Evaluate the safety of a dietary supplement using a Supplement Facts panel.

Do not exceed 100% of Daily Values Consider why you want it Compare product costs Read the label Check the expiration date Consider your medical history Approach herbal supplements with caution Report harmful effects

Starvation is a symptom of anorexia nervosa and is not the cause of the psychological condition True False

True

11. Describe vitamin D deficiency conditions.

Vitamin D deficiency can lead to a softening and bowing of the legs in children. this condition is known as rickets. Low blood levels of vitamin D are now believed to play an important role in the development of multiple sclerosis, type 1 diabetes, inflammatory bowel disease, infections, cardiovascular disease, cancer, and even neurological disorders such as Alzheimer's. More severe vitamin D deficiency interferes with calcium absorption; when vitamin D is deficient, only about 10 to 15% of the calcium in the diet can be absorbed, increasing the risk of abnormalities in bone structure. In children, vitamin D deficiency causes rickets; it is characterized by narrow rib cages known as pigeon breasts and by bowed legs (Figure 7.36). In adults, vitamin D deficiency causes a condition called osteomalacia. Bone deformities do not occur with osteomalacia because adults are no longer growing, but the bones are weakened because not enough calcium is available to form the mineral deposits needed to maintain healthy bone. Insufficient bone mineralization leads to fractures of the weight-bearing bones, such as those in the hips and spine. This lack of calcium in bones can precipitate or exacerbate osteoporosis, which is a loss of total bone mass, not just minerals (discussed further in Chapter 8). Osteomalacia is common in adults with kidney failure because the conversion of vitamin D to the active form is reduced in these patients.

Vitamin C

also called ascorbic acid, is a water-soluble vitamin that functions as an antioxidant in the blood and other body fluids Functions: Antioxidant - donates an electron or two to neutralize free radicals (made when cells are using a lot of oxygen), protecting other substances from damage Cofactor in: Collagen formation (most abundant protein in body and the matrix in which tissue is formed) Assists in making thyroxin, which regulates metabolic rate Physical stress raises Vit C needs (smokers should consider supplementing with Vitamin C, as it helps to neutralize free radicals. 35mg extra/d is recommended) Sources: (Is in all fruits and vegetables but very high in the following): Fruits Citrus (orange, grapefruit, tangerine, lemons, limes, etc) Kiwi Strawberries Vegetables Red and green bell pepper Broccoli Brussels sprouts Tomatoes and juice RDA: Men 90 mg/d Women 75 mg/d Smokers: additional 35 mg/d Destruction: easily destroyed by heat and oxygen (therefore raw fruits & vegetables usually have a higher Vit C content than their cooked counterparts) Deficiency disease: scurvy (lack of Vit C to make collagen allows capillaries to break causing hemorrhages , muscles [including heart] degenerate, teeth loosen; death comes from internal bleeding) UL: 2000 mg/d (2g) Toxicity symptoms: begin to see diarrhea at 2 g/d ; GI symptoms increase as the dose increases Other symptoms: Nausea Abdominal cramps May increase risk of kidney stones

Pantothenic Acid

is a B vitamin that is widely distributed in foods. It is particularly abundant in meat, eggs, whole grains, and legumes, and it is found in lesser amounts in milk, vegetables, and fruits. It is part of coenzyme A (CoA), which is needed for the breakdown of carbohydrates, fatty acids, and amino acids, as well as for the modification of proteins and the synthesis of neurotransmitters, steroid hormones, and hemoglobin. Pantothenic acid is also needed to form a molecule that is essential for the synthesis of cholesterol and fatty acids. The AI is 5 mg/day for adults. Pantothenic acid is relatively nontoxic, and there are insufficient data to establish a UL.

5. Describe the function of antioxidants

Antioxidant - donates an electron or two to neutralize free radicals (made when cells are using a lot of oxygen), protecting other substances from damage Some vitamins function as antioxidants, substances that protect against oxidative stress. Damage caused by oxidative stress has been related to everything from aging to heart disease, cancer, and Alzheimer's disease. Oxidative stress allows reactive oxygen molecules to steal electrons from other compounds, such as DNA, proteins, carbohydrates, or unsaturated fatty acids, resulting in changes in their structure and function. Reactive oxygen molecules are generated by normal oxygen-requiring reactions inside the body, such as cellular respiration, and come from environmental sources such as air pollution or cigarette smoke. Antioxidants act by reducing the formation of or destroying free radicals and other reactive oxygen molecules before they can cause damage Some antioxidants are produced in the body; others, such as vitamin C, vitamin E, and the mineral selenium

Biotin

B vitamin biotin is a coenzyme that functions in energy metabolism and glucose synthesis. This water-soluble vitamin is also important in the metabolism of fatty acids and amino acids. Good sources of biotin in the diet include cooked eggs, liver, yogurt, and nuts. Fruit and meat are poor sources. Bacteria in the gastrointestinal tract synthesize biotin, and some of this is absorbed into the body and helps meet our biotin needs. An AI of 30 μg/day has been established for adults Biotin deficiency in humans causes nausea, thinning hair, loss of hair color, a red skin rash, depression, lethargy, hallucinations, and tingling of the extremities. High doses of biotin have not resulted in toxicity symptoms; there is no UL for biotin.

Which of the following tools is the most accurate for determining body composition? underwater weighing skinfold thickness BMI

BMI

3. Describe how bioavailability affects vitamin requirements. Vitamins Absorption

Bioavailability- the extent to which the body can absorb nutrients About 40 to 90% of the vitamins in food are absorbed, primarily from the small intestine 1. Mouth- Chewing breaks food into small particles helping to release vitamins 2. Stomach- digestion of food releases vitamins. Some niacin is absorbed here 3. Gallbladder- releases bile which emulsifies fat and helps absorb fat soluble vitamins 4. Pancreas- secretes digestive enzymes that help release vitamins from food. 5. Small intestine- fat soluble vitamins are incorporated into micelles and absorbed by simple diffusion. Inside the mucosal cells, they are packaged in chylomicrons which enter the lymph. 6. Water soluble vitamins are absorbed from the small intestine directly into the blood. Many depend on energy requiring transport systems or must bind to specific molecules in the gastrointestinal tract to be absorbed 7. Large intestin- bacteria synthesize small amounts of vitamins, some of which are absorbed.

7. Explain the roles of folate and vitamin B12 in the body.

Both act form that is active for DNA synthesis.

9. Determine food sources of water-sol vitamins.

Diary products, meats, animal products, eggs, whole grains

15. Explain how the safety of dietary supplements is monitored.

Dietary Supplement Health and Education Act (DSHEA) of 1994 defined the term dietary supplement and created labeling standards FDA established "current Good Manufacturing Practice" (cGMP) regulations Requires manufacturers to test their products to ensure identity, purity, strength, and composition FDA pre-market review required if ingredient not sold in the US before October 15, 1994

14. List some population groups that may benefit from taking vitamin and mineral supplements.

Dieters- People who consume fewer than 1600 Calories/day should take a multivitamin/multimineral supplement. Vegans and those who eliminate all dairy foods- To obtain adequate vitamin B12, people who do not eat animal products need to take supplements or consume vitamin B12-fortified foods. Because dairy products are an important source of calcium and vitamin D, those who do not consume dairy products may benefit from taking supplements that provide calcium and vitamin D. Infants and children- Supplemental fluoride, vitamin D, and iron are recommended under certain circumstances. Young women and pregnant women- Women of childbearing age should consume 400 μg of folic acid daily from either fortified foods or supplements. Supplements of iron and folic acid are recommended for pregnant women, and multivitamin/multimineral supplements are usually prescribed during pregnancy. Older adults- Because of the high incidence of atrophic gastritis in adults over age 50, vitamin B12 supplements or fortified foods are recommended. It may also be difficult for older adults to meet the RDAs for vitamin D and calcium, so supplements of these nutrients are often recommended. Individuals with dark skin pigmentation- People with dark skin may be unable to synthesize enough vitamin D to meet their needs for this vitamin and may therefore require supplements. Individuals with restricted diets-Individuals with health conditions that affect what foods they eat or how nutrients are used may require vitamin and mineral supplements. People taking medications-Medications may interfere with the body's use of certain nutrients. Cigarette smokers and alcohol users- People who smoke heavily require more vitamin C and possibly vitamin E than do nonsmokers[7.22], [7.44] Alcohol consumption inhibits the absorption of B vitamins and may interfere with B vitamin metabolism.

Vitamin D

Different from all other nutrients in that the body can synthesize it, w/ the help of sunlight. Therefore, Vit D is not an essential nutrient. Actually a hormone [messenger]. 2 chemical reactions in body to make active Vit D: liver & kidney. Functions: Mineralization of the bones (raises blood calcium by increasing absorption of calcium & phosphorus from intestine) Many other tissues have Vit D receptors (immune system, pancreas, brain & nervous system, etc); much research in progress now Gene expression: increases the production of proteins necessary for absorption of calcium Found in: Milk Almond milk Yogurt Cheese Mushrooms Salmon Precursor: made from cholesterol Sources: (besides sunlight) Despite Vit D fortification of milk, average intake in US falls short of recommendations. Oily (fatty) fish like salmon, mackerel, sardines are best natural sources. Vegans: need Vit D fortified soymilk or supplements (if no sunlight) Time needed in sun: Fair-skinned : 10-15 minutes 2-3x/week WITHOUT sunscreen Darker-skinned: because skin pigment provides some protection from sun, need 3 -6x as long to make same amount Vit D Dietary Guideline for Americans: People w/ dark skin & those with insufficient exposure to sunlight should consume extra Vit D from fortified food or supplements. AI: (modified from 2011 DRIs, Fd & Nutrition board, Institute of Medicine, Nat'l Academy of Sciences) adults (19-70 yr) 15 µg/d (>70 yr) 20 µg/d D2: ergocalciferol (plant version) D3: cholecalciferol (animal form) DV: 400 IU (10 µg) Toxicity: can cause calcification of soft tissues. Supplements should be kept out of reach of children UL: Adults 100 µg/d (~ 4000 IU) [conversion: 1µg cholecalciferol = 40 IU Vitamin D] Deficiency diseases: Children: rickets (bowed legs) Adults: osteomalacia ( osteo = bone, malacia = softening)

Vitamin E: alpha tocopherol

Function: fat soluble antioxidant Primary defender against adverse effects of free radicals Main action: stops chain reaction of free radicals producing more free radicals Protects cell membranes by preventing oxidation of PUFA Also protects Vitamin A (and precursor beta-carotene) Sources: Oils from vegetable sources [not just "vegetable" oil] (Vitamin E is in there protecting the MUFA and PUFA) Products of oils: margarine, salad dressings vitamin E deficiency, red blood cell membranes may rupture, causing a type of anemia called hemolytic anemia. This is most common in premature infants. Destruction: destroyed by heat (like deep-fat frying, so french fries are NOT a Vitamin E source. (Also, trans fats are produced and the Vitamin C of the natural potato is destroyed) RDA: 15 mg/d Deficiency: normally is rare. Two conditions that respond to Vitamin E treatment: Fibrocystic breast disease (benign cysts in breasts) Blood flow abnormality in legs that causes cramping UL: 1000mg/d Toxicity: rare. Extreme high doses of Vit E can interfere w/ blood clotting action of Vit K

Vitamin B12

Functions: coenzyme, used in new cell synthesis Maintains sheath that surrounds & protects nerve cells Reforms folate coenzyme Deficiency disease: pernicious anemia (when B12 cannot be absorbed) Deficiency takes a long time to occur, because the body recycles B12, reabsorbing it over and over. Deficiency symptoms: Anemia (large cell), fatigue, degeneration of peripheral nerves progressing to paralysis, sore tongue, loss of appetite Sources: Foods of animal origin (milk, cheese, eggs, fish, chicken, etc) and blue-green algae Fortified cereals Vegans need reliable source, like B12-fortified plant milk (however the B12 will have likely originated from an animal source, blue-green algae, or have been concocted in a laboratory) Humans cannot synthesize B12 but some B12 (a very small amount) is synthesized by the gut flora in humans and absorbed in the ileum. RDA: adults 2.4 µg/d Destruction: easily destroyed by microwave cooking; so cook meats and milk items in the oven or on top of the stove to preserve B12. Toxicity symptoms: none reported Vitamin B12, also known as cobalamin, is a water-soluble vitamin necessary for the production of ATP from certain fatty acids, to maintain the myelin coating on nerves, and for a reaction that converts homocysteine to methionine and converts folate to the form that is active for DNA synthesis. When vitamin B12 is deficient, homocysteine levels rise, and folate is trapped in an inactive form. Without adequate active folate, DNA synthesis slows, red blood cells do not divide normally, and macrocytic anemia develops. Lack of vitamin B12 also leads to degeneration of the myelin that coats nerves including those in the spinal cord and brain, resulting in symptoms such as numbness and tingling, abnormalities in gait, memory loss, and disorientation. If not treated, vitamin B12 deficiency can cause irreversible nerve damage and eventually death.

2. Discuss the dietary sources of vitamins.

Grains: Thiamin, Riboflavin, Niacin, Pantothenic acid, B6, Folate, E Vegetables: Riboflavin, Niacin, B6, Folate, C, A, E, &K Fruits: Folate, C and A Dairy: Riboflavin, A, D, B12 Protein: Thiamin, Riboflavin, Niacin, Biotin, Pantothenic acid, folate, B12, A, D, K Some vitamins are easily damaged by light, heat, and time. That is why some milks are sold in yellow containers (to prevent from light damage), some vitamins are lost during the cooking process, and the vitamin content of some foods decreases the longer they are stored. The cooking process will either help preserve or will eliminate vitamins from foods. Steaming some vegetables, like broccoli and spinach, can actually help to make the nutrient content more absorbable by destroying the oxalic acid (a phytochemical) that inhibits the absorption of some nutrients. However, overcooking will destroy these nutrients too. The high heat of frying can destroy vitamins Long-term cooking (slow-cooker) has a tendency to destroy vitamins over the long cooking process If you boil vegetables, the water-soluble vitamins, tend to "leach" from the food into the water in the pot. You will be left with a less nutritious food to eat.

Folate (Folic Acid)

is a B vitamin that is needed for the synthesis of DNA and the metabolism of some amino acids. Cells must synthesize DNA in order to replicate, so this water-soluble vitamin is particularly important in tissues in which cells are dividing rapidly, such as the intestines, skin, embryonic and fetal tissues, and bone marrow, where red blood cells are made. When folate is deficient, cells cannot divide normally. This leads to one of the most notable symptoms of folate deficiency: a type of anemia called microcytic anemia. Other symptoms of folate deficiency include poor growth, problems with nerve development and function, diarrhea, and inflammation of the tongue. Folate is also important during pregnancy for the development of the embryo. Low folate intake increases the risk of birth defects called neural tube defects. Neural tube defects are not a true folate-deficiency symptom because not every pregnant woman with inadequate folate levels will bear a child with a neural tube defect. Instead, neural tube defects are probably due to a combination of factors that include low folate levels and a genetic predisposition. The formation of the neural tube, which later develops into the brain and spinal cord, occurs very early during pregnancy. Therefore, to reduce the risk of neural tube defects, a woman's folate status must be adequate before she becomes pregnant and during the critical early days of pregnancy. Sources: Fourth of 4 vits added to enriched / fortified refined grains Fortified grains (began in 1996, show chart pg 328) 1 slice whole grain bread: 2% DV; 1 slice fortified white bread: ~7% DV Leafy green vegetables, like spinach and broccoli Legumes, seeds RDA: adults 400 µg/d (also DV) Destruction: easily destroyed by heat and oxygen Upper Level (UL): 1000 µg/d (only 2.5 x RDA; too much folate can mask a B12 deficiency)

Riboflavin

is a B vitamin that provides a visible indicator of excessive consumption; the excess is excreted in the urine, turning it a bright fluorescent yellow. The color may surprise you, but it is harmless. No adverse effects of high doses of riboflavin from either foods or supplements have been reported. is a water-soluble vitamin that forms two active coenzymes. They serve as electron carriers that function in the reactions needed to produce ATP from carbohydrate, fat, and protein. Riboflavin is also involved directly or indirectly in converting a number of other vitamins, including folate, niacin, vitamin B6, and vitamin K, into their active forms. When riboflavin is deficient, injuries heal poorly because new cells cannot grow to replace the damaged ones. The tissues that grow most rapidly, such as the skin and the linings of the eyes, mouth, and tongue, are the first to be affected. Deficiency causes symptoms such as cracking of the lips and at the corners of the mouth; increased sensitivity to light; burning, tearing, and itching of the eyes; and flaking of the skin around the nose, eyebrows, and earlobes.

Vitamin B6

is a water-soluble vitamin that is particularly important for amino acid and protein metabolism. There are three forms of vitamin B6: pyridoxal, pyridoxine, and pyridoxamine. These can be converted into the active coenzyme pyridoxal phosphate, which is needed for the activity of more than 100 enzymes. For example, the coenzyme form of vitamin B6 is needed to produce hemoglobin for red blood cell synthesis, to convert tryptophan to niacin, for the metabolism of glucose and amino acids, and for the synthesis of lipids needed for nerve function Function: coenzyme PLP, active in amino acid metabolism; allows body to make non-essential amino acids. Helps convert tryptophan to niacin and to serotonin (neurotransmitter) Very important for neurological function It is Stored: unlike other B-vitamins, can be stored in muscles (and turns over slowly) Absorbed by passive diffusion; even extremely large doses are well absorbed Deficiency symptoms: Anemia (small-cell type; due to decreased hemoglobin synthesis) synthesis of key neurotransmitters diminishes, causing depression and confusion; later convulsions Sources: Bananas Animal muscle foods Widespread in foods No adverse effects from high intake from foods RDA: adults (19-50): 1.3 mg/d Upper Level (UL): 100mg/d

Thiamin

is sometimes called vitamin B1 Beriberi, the disease that results from a deficiency of this vitamin, flourished in East Asian countries for over 1000 years. Thiamin is a water-soluble vitamin that functions as a coenzyme in the breakdown of glucose to provide energy. It is particularly important for nerve function because glucose is the energy source for nerve cells. its role in energy metabolism, thiamin is needed for the synthesis of neurotransmitters, the metabolism of other sugars and certain amino acids, and the synthesis of ribose and deoxyribose, sugars that are part of the structure of RNA (ribonucleic acid) and DNA, respectively. When thiamin intake is deficient, neurological symptoms such as mental confusion, weakness, impaired tendon reflexes, and tingling and lack of feeling in the hands and feet (dry beriberi), or cardiovascular symptoms such as rapid heart rate, enlargement of the heart, and accumulation of fluid in the tissues (wet beriberi) occur. Thiamin deficiency can also result in Wernicke-Korsakoff syndrome, which involves confusion, loss of coordination, vision changes, and hallucinations and can progress to coma and death. It occurs most often in alcoholics because alcohol decreases thiamin absorption, and diets high in alcohol are typically low in micronutrients. It has also been identified in those with eating disorders, in those on long-term intravenous nutrition, and in individuals who have undergone gastric bypass surgery

Vitamin K

the conversion of prothrombin to thrombin reaction requires vitamin K Like Vitamin D, can be obtained from a non-food source: bacteria in gut can synthesize. Function: primarily in blood clotting; part of a multi-player sequence Also participates in metabolism of bone proteins; without Vit K a bone protein cannot bind to the minerals that normally form bones, resulting in low bone density (We normally think only of Calcium regarding bone density, but Vit K plays a role, & so do other minerals, as we shall see in Chap 8) AI: Men 120 µg/d Women 90 µg/d DV: 80 µg Deficiency: primary deficiency rare, but secondary problems: Fat malabsorption: low Vitamin K absorption Antibiotics: kill gut bacteria (so need to get more by eating yogurt!) Anticoagulant drugs: (warfarin). Interferes w/Vit K metabolism. If not monitored correctly, xs bleeding can be fatal. Toxicity: not common, no adverse, no UL Sources: bacterial synthesis (cannot meet total needs this way) Liver Leafy green vegs (spinach, collards), Brussels sprouts, cabbage Soy/soybean oil (salad dressings & mayo if made from soy oil) Vitamin K is also needed for the synthesis of several proteins involved in bone formation and breakdown, inhibition of blood vessel calcification, and regulation of cell growth A frank deficiency is rare in adults because vitamin K is synthesized by bacteria in the large intestine. Deficiency can be precipitated by a poor diet; Crohn's disease, which damages the colon, limiting absorption; and long-term antibiotic use, which kills the bacteria in the gastrointestinal tract that synthesize the vitamin. Newborns are at risk of deficiency because when a baby is born, no bacteria are present in the GI tract to synthesize vitamin K. In addition, newborns are at risk because little vitamin K is transferred to the baby from the mother before birth, and breast milk is a poor source of this vitamin. To ensure normal blood clotting, infants are typically given a vitamin K injection within six hours of birth.

Visceral fat is considered more harmful to health than subcutaneous fat and this is due to: visceral fat being more prone to men than to women visceral fat being stored around the abdomen area and is more metabolically active subcutaneous fat being stored underneath the skin and aiding in body temperature regulation

visceral fat being stored around the abdomen area and is more metabolically active