Protein Chapter 3 and Vitamins Chapter 5. Protein Chapter 3.

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Protein Chapter 3 and Vitamins Chapter 5

Transcript of Protein Chapter 3 and Vitamins Chapter 5. Protein Chapter 3.

Page 1: Protein Chapter 3 and Vitamins Chapter 5. Protein Chapter 3.

Protein

Chapter 3

and

Vitamins

Chapter 5

Protein

Chapter 3

and

Vitamins

Chapter 5

Page 2: Protein Chapter 3 and Vitamins Chapter 5. Protein Chapter 3.

Protein

Chapter 3

Protein

Chapter 3

Page 3: Protein Chapter 3 and Vitamins Chapter 5. Protein Chapter 3.

ProteinProtein

• A component of every living cell

• Accounts for 20% of adult weight

• Immune to the controversy over optimal intake

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Protein—(cont.)Protein—(cont.)• Amino acids

– Basic building blocks of protein

– Composed of carbon, hydrogen, oxygen, and nitrogen atoms

– Twenty common amino acids

o Nine are considered essential in the diet because the body cannot make them—indispensable; they must be consumed through food.

o Eleven are considered nonessential in the diet because they can be made by the body—dispensable. However…

o Conditionally essential amino acids-situation arises when insufficient substrate(s) levels for synthesis of non-essential amino acids and/or a problem with the metabolic machinery to make non-essential amino acids occurs

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Essential Amino AcidsEssential Amino Acids

• Histidine

• Isoleucine

• Leucine

• Lysine

• Methionine

• Phenylalanine

• Threonine

• Tryptophan

• Valine

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Nonessential Amino AcidsNonessential Amino Acids

• Alanine

• Arginine

• Asparagine

• Aspartic acid

• Cystine (cysteine)

• Glutamic acid

• Glutamine

• Glycine

• Proline

• Serine

• Tyrosine

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Protein—(cont.)Protein—(cont.)

• Protein structure

– Most contain several dozen to several hundred amino acids.

– Shape (i.e. structure) determines function.

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Protein—(cont.)Protein—(cont.)

• Functions of protein

– Major structural and functional component of every living cell

– Body structure and framework

– Enzymes

– Other body secretions and fluids

– Acid–base balance

– Transport molecules

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Protein—(cont.)Protein—(cont.)

• Functions of protein—(cont.)

– Other compounds

– Some amino acids have specific functions within the body.

– Fueling the body

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Protein—(cont.)Protein—(cont.)• How the body handles protein

– Digestion

o Begins in the stomach

o Hydrochloric acid converts pepsinogen to the active enzyme pepsin.

o Small intestine is the principal site of protein digestion.

o Enzymes located on the surface of the cells that line the small intestine complete the digestion.

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Protein—(cont.)Protein—(cont.)

• How the body handles protein—(cont.)

– Absorption

o Amino acids, and sometimes a few dipeptides or larger peptides, are absorbed through the mucosa of the small intestine.

– Metabolism

o Liver acts as a clearinghouse. Retains amino acids to make liver cells,

nonessential amino acids, and plasma proteins such as heparin, prothrombin, and albumin

Regulates the release of amino acids into the bloodstream

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Protein—(cont.)Protein—(cont.)

• How the body handles protein—(cont.)

– Metabolism—(cont.)

o Liver acts as a clearinghouse.—(cont.)

Removes the nitrogen from amino acids

Converts amino acids to fatty acids which form triglycerides for storage in adipose tissue

Forms urea from the nitrogenous wastes of protein

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Protein—(cont.)Protein—(cont.)

• Protein synthesis

– Complicated but efficient process that quickly assembles amino acids into proteins the body needs

– Part of what makes every individual unique is the minute differences in body proteins.

– Important concepts

o Protein turnover, metabolic pool, and nitrogen balance

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Important ConceptsImportant Concepts

Protein turnover

• Continuous process

• Body proteins vary in their rate of turnover.

Metabolic pool

• Contains supply of each amino acid

• Consists of recycled amino acids from body proteins that have broken down and also amino acids from food

• In a constant state of flux

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Important Concepts—(cont.)Important Concepts—(cont.)

• Nitrogen balance

– Reflects the state of balance between protein breakdown and protein synthesis

– Determined by comparing the amount of nitrogen consumed (intake) with the amount of nitrogen excreted (output)

– Healthy adults are in neutral nitrogen balance.

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Important Concepts—(cont.)Important Concepts—(cont.)

• Nitrogen balance—(cont.)

– Positive nitrogen balance: when protein synthesis exceeds protein breakdown (e.g. growth, pregnancy)

– Negative nitrogen balance: an undesirable state that occurs when protein breakdown exceeds protein synthesis (e.g. illness, insufficient dietary protein)

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Protein—(cont.)Protein—(cont.)

• Protein catabolism for energy

– Counterproductive-proteins (enzymes) are required to get energy from carbohydrates and lipids

– Over time, loss of lean body tissue occurs.

– Loss of 30% of body protein causes

o Impaired breathing

o Altered immune function

o Altered organ function

o Ultimately death

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Sources of Protein Sources of Protein

• Protein quality

– Differs based on content of essential amino acids and digestibility of the protein

– Quality can become a crucial concern.

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Sources of Protein—(cont.)Sources of Protein—(cont.)

• Complete and incomplete proteins

– Complete proteins

o High biologic value

o Provide adequate amounts and proportions of all essential amino acids needed for protein synthesis necessary to support tissue growth and repair

o Animal proteins, soy, quinoa protein are complete proteins- but with quinoa have digestibility of protein issue- explain

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Sources of Protein—(cont.)Sources of Protein—(cont.)• Complete and incomplete proteins—(cont.)

– Incomplete proteins

o Lack adequate amounts of one or more essential amino acids

o Except for soy and quinoa protein, all plants are sources of incomplete proteins.

o Gelatin is also an incomplete protein.

– Complementary proteins

o Two proteins that when combined provide adequate amounts and proportions of all essential amino acids needed to support protein synthesis

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Examples of Complementary Plant ProteinsExamples of Complementary Plant Proteins

• Black beans and rice

• Bean tacos

• Pea soup with toast

• Lentil and rice curry

• Falafel sandwich (ground chickpeas on pita)

• Peanut butter sandwich

• Pasta e fagioli (pasta with white beans)

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Examples of a Plant Protein Complemented by a Small Amount of an

Animal Protein to Form a Complete Protein

Examples of a Plant Protein Complemented by a Small Amount of an

Animal Protein to Form a Complete Protein

• Bread pudding

• Rice pudding

• Corn pudding

• Cereal and milk

• Macaroni and cheese

• Cheese fondue

• French toast

• Cheese sandwich

• Vegetable quiche

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Dietary Reference IntakesDietary Reference Intakes

• RDAs

– For healthy adults is 0.8 g/kg

– Acceptable Macronutrient Distribution Range for protein for adults is 10% to 35% of total calories.

• RDA for healthy adults does not apply to others than healthy adults

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Dietary Reference Intakes—(cont.)Dietary Reference Intakes—(cont.)• Protein deficiency

– Protein–energy malnutrition (PEM)

o Kwashiorkor Results mainly from acute critical illnesses Enough energy but not enough protein Get swollen abdomen Aggressive nutritional support is used to restore metabolic

balance as quickly as possible.

o Marasmus Occurs secondary to chronic diseases Not enough energy or protein Skin and bones appearance Nutritional therapy is started slowly and advanced

gradually.

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Dietary Reference Intakes—(cont.)Dietary Reference Intakes—(cont.)

• Protein excess

– No proven risks from eating an excess of protein

– Conflicting data as to whether high-protein diets increase the risk of:

o Osteoporosis

o Renal stones

o Renal disease

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Protein in Health PromotionProtein in Health Promotion

• Vegetarian diets

– Pure vegetarians or vegans

o Eat no animal products.

o Eat only plants.

o They form the smallest group of vegetarians

o Must eat a wide variety of plant foods to get sufficient of all essential amino acids

o Vitamin B12 usually comes from plant foods with vitamin B12 added to food prior to purchase or if that fails via vitamin B12 in tablet form.

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Protein in Health Promotion—(cont.)Protein in Health Promotion—(cont.)

• Vegetarian diets—(cont.)

– Most vegetarians are

o Lacto-vegetarians, whose diets include milk products

o Lacto-ovo vegetarians, whose diets include milk products and eggs

• Nutrients of concern

– Most vegetarian diets meet or exceed the RDA for protein and are nutritionally adequate across the life cycle.

– Iron, zinc, calcium, vitamin D, omega-3 fatty acid, and iodine are nutrients of concern.

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Protein in Health Promotion—(cont.)Protein in Health Promotion—(cont.)

• Is vegetarianism for everyone?

– A personal choice, subject to personal interpretation

– Proper planning means paying close attention to the nutrients of concern and using a vegetarian food guide for planning.

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Vitamins

Chapter 5

Vitamins

Chapter 5

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VitaminsVitamins

• In 1913, thiamin was discovered as the first vitamin, the “vital amine” necessary to prevent the deficiency disease beriberi.

• Today, 13 vitamins have been identified as important for human nutrition.

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Understanding Vitamins Understanding Vitamins • Organic compounds made of carbon, hydrogen, oxygen, and sometimes nitrogen or

other elements

• Some vitamins facilitate biochemical reactions within cells

• Essential to life

• Individual molecules

• Do not provide energy (calories), but some are needed for metabolism of energy

• Needed in microgram or milligram quantities

• Too little of a food source(s) of a vitamin leads to deficiencies of that vitamin lead to loss of function (role) of vitamins

• Too much of a food source(s) or supplement of a vitamin leads to toxicities lead to impairment of some bodily functions-fat soluble vitamins are particularly a problem here but some water soluble vitamins can also be affected

• A complete listing of the effects of various vitamin deficiencies and toxicities is available online

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•Vitamins may exist in more than one form

– Different forms perform different functions in the body.

– Provitamins

•Vitamins are essential

– With few exceptions, the human body cannot make vitamins. Humans can for example make vitamin D

• Some vitamins are coenzymes

– Many enzymes cannot function without a coenzyme, and many coenzymes are vitamins.

Understanding Vitamins—(cont.)Understanding Vitamins—(cont.)

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Understanding Vitamins—(cont.)Understanding Vitamins—(cont.)

• Some vitamins are antioxidants

– Free radicals are produced continuously in cells as they burn oxygen during normal metabolism.

o Oxidize body cells and DNA in their quest to gain an electron and become stable

– Antioxidants protect body cells from being oxidized (destroyed) by free radicals.

– Major antioxidants are vitamin C, vitamin E, and beta-carotene.

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Understanding Vitamins—(cont.)Understanding Vitamins—(cont.)

• Some vitamins are used as food additives

– Some foods have vitamins added to them simply to boost their nutritional content.

• Vitamins as drugs

– In megadoses, vitamins function like drugs, not nutrients. e.g. vitamin E can lower ability to clot

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Vitamin Classifications Based on Solubility

Vitamin Classifications Based on Solubility

• Fat-soluble vitamins

– Characteristics

o Sources are the fat and oil portion of foods.

o Absorption: fat encased in chylomicrons that enter the lymphatic system before circulating in the bloodstream

o Transportation through the blood occurs by attaching to protein carriers because fat is not soluble in watery blood.

o When consumed in excess, stored primarily in liver and adipose tissue

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Vitamin Classifications Based on Solubility—(cont.)

Vitamin Classifications Based on Solubility—(cont.)

• Fat-soluble vitamins

– Characteristics—(cont.)

o Can be toxic if consuming high intakes through supplements –why?

o Generally do not have to be consumed daily because the body can retrieve them from storage as needed

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Vitamin Classifications Based on Solubility—(cont.)

Vitamin Classifications Based on Solubility—(cont.)

• Vitamins A,D,E,K are fat soluble

• B vitamins, non-B vitamins and vitamin C are water soluble.

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Vitamin Classifications Based on Solubility—(cont.)

Vitamin Classifications Based on Solubility—(cont.)

• Vitamin A

– Preformed vitamin A is found only in animal sources.

– Also includes provitamin A carotenoids

o Natural plant pigments found in deep yellow and orange fruits and vegetables and most dark-green leafy vegetables

o Beta-carotene, lutein, and lycopene are among the most commonly known carotenoids.

Page 42: Protein Chapter 3 and Vitamins Chapter 5. Protein Chapter 3.

Vitamin Classifications Based on Solubility—(cont.)

Vitamin Classifications Based on Solubility—(cont.)

• Vitamin A—(cont.)

– Best known for its roles in normal vision, reproduction, growth, and immune system functioning

– Body can store up to a year’s supply of vitamin A.

– Only preformed vitamin A is toxic in high doses.

– Beta carotene is nontoxic.

– Hypercarotenemia –orange-coloured skin in Caucasians

Page 43: Protein Chapter 3 and Vitamins Chapter 5. Protein Chapter 3.

Vitamin Classifications Based On Solubility—(cont.)

Vitamin Classifications Based On Solubility—(cont.)

• Vitamin D

– Unique in that the body has the potential to make all of the vitamin D it needs if exposure to sunlight is optimal and liver and kidney function are normal

– Another distinctive feature of vitamin D is that it acts like a hormone because it is synthesized in one part of the body (skin) and stimulates functional activity elsewhere.

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Vitamin Classifications Based on Solubility—(cont.)

Vitamin Classifications Based on Solubility—(cont.)

• Vitamin D—(cont.)– Primary function of vitamin D is to maintain normal

blood concentrations of calcium and phosphorus. – Calcium and phosphorous are used for bone and teeth

development and maintenance– Vitamin D is important for immune function. – It is possible to fulfill the vitamin D requirement by

taking a daily 15-minute walk in the sun under optimal conditions.

– Winter, living in northern latitudes, and being of black race and older age are associated with low vitamin D synthesis.

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Vitamin Classifications Based on Solubility—(cont.)

Vitamin Classifications Based on Solubility—(cont.)

• Vitamin D—(cont.)

– Dietary source is considered essential because few people meet optimal conditions.

o Vitamin D occurs naturally in only a few foods.

– Many experts believe the AI for vitamin D is set too low.

– Overt deficiency of vitamin D causes poor calcium absorption.

o Rickets and osteomalacia

– Current upper limit for vitamin D is set at 100 µg/day (4000 IU/day) for ages 9 years and older.

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Vitamin Classifications Based on Solubility—(cont.)

Vitamin Classifications Based on Solubility—(cont.)

• Vitamin E

– Generic term that describes a group of at least eight naturally occurring compounds

– Alpha-tocopherol is considered the most biologically active form of vitamin E.

– Functions as the primary fat-soluble antioxidant in the body

– Protects polyunsaturated fatty acids (PUFAs) and other lipid molecules, such as LDL cholesterol, from oxidative damage

Page 47: Protein Chapter 3 and Vitamins Chapter 5. Protein Chapter 3.

Vitamin Classifications Based on Solubility—(cont.)

Vitamin Classifications Based on Solubility—(cont.)

• Vitamin E—(cont.)– Need increases as the intake of PUFA increases. – Megadoses may help protect against atherosclerosis,

some types of cancer, cataracts, age-related macular degeneration, Parkinson’s disease, and Alzheimer’s disease.

– Deficiency can occur in very specific instances. o Premature infants o May occur secondary to a genetic abnormality or

malabsorption syndromes such as cystic fibrosis and short bowel syndrome

Page 48: Protein Chapter 3 and Vitamins Chapter 5. Protein Chapter 3.

Vitamin Classifications Based on Solubility—(cont.)

Vitamin Classifications Based on Solubility—(cont.)

• Vitamin E—(cont.)

– Signs and symptoms of deficiency include peripheral neuropathy, ataxia, and ultimately death.

• Vitamin K

– Occurs naturally in two forms

o Phylloquinone, found in plants

o Menaquinones, which are synthesized in the intestinal tract by bacteria

Page 49: Protein Chapter 3 and Vitamins Chapter 5. Protein Chapter 3.

Vitamin Classifications Based on Solubility—(cont.)

Vitamin Classifications Based on Solubility—(cont.)

• Vitamin K—(cont.)

– Coenzyme essential for the synthesis of prothrombin

– Clinically significant vitamin K deficiency is defined as vitamin K–responsive hypoprothrombinemia.

o Characterized by an increase in prothrombin time

– Deficiency does not occur from inadequate intake but may occur secondary to malabsorption syndromes or the use of certain medications that interfere with vitamin K metabolism or synthesis, such as anticoagulants and antibiotics.

Page 50: Protein Chapter 3 and Vitamins Chapter 5. Protein Chapter 3.

Vitamin Classifications Based on Solubility—(cont.)

Vitamin Classifications Based on Solubility—(cont.)

• Water-soluble vitamins

– Thiamin

o Coenzyme in the metabolism of carbohydrates and branched-chain amino acids

o Deficiency Beriberi (what is beriberi?)

o Beriberi has been virtually eliminated.

o Deficiency is usually seen only in alcoholics.

o No adverse effects have been noted from high intakes of thiamin.

Page 51: Protein Chapter 3 and Vitamins Chapter 5. Protein Chapter 3.

Vitamin Classifications Based on Solubility—(cont.)

Vitamin Classifications Based on Solubility—(cont.)

• Water-soluble vitamins—(cont.)

– Riboflavin

o Vitamin B 2 is an integral component of the coenzymes flavin adenine dinucleotide (FAD) and flavin mononucleotide (FMN) that function to release energy from nutrients in all body cells.

o Milk and dairy products contribute the most riboflavin to the diet.

Page 52: Protein Chapter 3 and Vitamins Chapter 5. Protein Chapter 3.

Vitamin Classifications Based on Solubility—(cont.)

Vitamin Classifications Based on Solubility—(cont.)

• Water-soluble vitamins—(cont.)

– Riboflavin—(cont.)

o Biochemical signs of inadequate riboflavin status can appear after only a few days of poor intake.

o Elderly and adolescents are at greatest risk for riboflavin deficiency.

o Deficiency symptoms include sore throat, cheilosis, stomatitis, glossitis, and dermatitis.

o Certain diseases, such as cancer, heart disease, and diabetes, precipitate or exacerbate riboflavin deficiency.

Page 53: Protein Chapter 3 and Vitamins Chapter 5. Protein Chapter 3.

Vitamin Classifications Based on Solubility—(cont.)

Vitamin Classifications Based on Solubility—(cont.)

• Water-soluble vitamins—(cont.)

– Niacin

o Vitamin B 3 exists as nicotinic acid and nicotinamide.

o Body can make it from the amino acid tryptophan.

o Niacin requirements are stated in niacin equivalents (NEs).

o Part of the coenzymes nicotinamide adenine dinucleotide (NAD) and nicotinamide adenine dinucleotide phosphate (NADP), which are involved in energy transfer reactions in the metabolism of glucose, fat, and alcohol in all body cells

Page 54: Protein Chapter 3 and Vitamins Chapter 5. Protein Chapter 3.

Vitamin Classifications Based on Solubility—(cont.)

Vitamin Classifications Based on Solubility—(cont.)

• Water-soluble vitamins—(cont.)

– Niacin—(cont.)

o Pellagra, the disorder caused by severe niacin deficiency, is rare in the United States and usually is seen only in alcoholics.

o Niacin deficiency may be treated with niacin, tryptophan, or both.

o Large doses of niacin in the form of nicotinic acid (1–6 g/day) are used therapeutically to lower total cholesterol and LDL cholesterol and raise high-density lipoprotein (HDL) cholesterol.

Page 55: Protein Chapter 3 and Vitamins Chapter 5. Protein Chapter 3.

Vitamin Classifications Based on Solubility—(cont.)

Vitamin Classifications Based on Solubility—(cont.)

• Water-soluble vitamins—(cont.)

– Vitamin B6

o Vitamin B6 and pyridoxine are group names for six related compounds that include pyridoxine, pyridoxal, and pyridoxamine.

o Plays a role in the synthesis, catabolism, and transport of amino acids and in the conversion of tryptophan to niacin

Page 56: Protein Chapter 3 and Vitamins Chapter 5. Protein Chapter 3.

Vitamin Classifications Based on Solubility—(cont.)

Vitamin Classifications Based on Solubility—(cont.)

•Water-soluble vitamins—(cont.)

– Vitamin B6—(cont.)

o Deficiencies of vitamin B6, folic acid, and vitamin B1 2 lead to an increase in blood homocysteine levels.

o Supplements of vitamin B6 have been used for a variety of other conditions, although supportive evidence is lacking.

o High intake of vitamin B6 from food does not pose any danger.

Page 57: Protein Chapter 3 and Vitamins Chapter 5. Protein Chapter 3.

Vitamin Classifications Based on Solubility—(cont.)

Vitamin Classifications Based on Solubility—(cont.)

•Water-soluble vitamins—(cont.)

– Vitamin B6—(cont.)

o Deficiencies of vitamin B6 are uncommon but are usually accompanied by deficiencies of other B vitamins.

o Secondary deficiencies are related to alcohol abuse and to other drug therapies such as isoniazid, the antituberculosis drug that acts as a vitamin B6 antagonist.

Page 58: Protein Chapter 3 and Vitamins Chapter 5. Protein Chapter 3.

Vitamin Classifications Based on Solubility—(cont.)

Vitamin Classifications Based on Solubility—(cont.)

• Water-soluble vitamins—(cont.)

– Folate

o Generic term for this B vitamin that includes both synthetic folic acid found in vitamin supplements and fortified foods and naturally occurring folate in food such as green leafy vegetables, dried peas and beans, seeds, liver, and orange juice

Page 59: Protein Chapter 3 and Vitamins Chapter 5. Protein Chapter 3.

Vitamin Classifications Based on Solubility—(cont.)

Vitamin Classifications Based on Solubility—(cont.)

•Water-soluble vitamins—(cont.)

– Folate—(cont.)

o Major function is in the synthesis of DNA.

o Folate is recycled through the intestinal tract.

o Folate deficiency impairs DNA synthesis and cell division and results in macrocytic anemia and other clinical symptoms.

Page 60: Protein Chapter 3 and Vitamins Chapter 5. Protein Chapter 3.

Vitamin Classifications Based on Solubility—(cont.)

Vitamin Classifications Based on Solubility—(cont.)

•Water-soluble vitamins—(cont.)

– Folate—(cont.)

o Adequate intake of folate before conception and during the first trimester of pregnancy reduces the risk of neural tube defects.

o Upper limit for folic acid is 1000 µg/day.

o Consistently high intakes of folate can mask vitamin B1 2 deficiency.

Page 61: Protein Chapter 3 and Vitamins Chapter 5. Protein Chapter 3.

Vitamin Classifications Based on Solubility—(cont.)

Vitamin Classifications Based on Solubility—(cont.)

• Water-soluble vitamins—(cont.)

– Vitamin B1 2o Cobalamin

o Vitamin B1 2 has important role in maintaining the myelin sheath around nerves.

o Large doses of folic acid can alleviate the anemia caused by vitamin B1 2 deficiency (a function of both vitamins), but folic acid cannot halt the progressive neurologic impairments that only vitamin B1 2 can treat.

Page 62: Protein Chapter 3 and Vitamins Chapter 5. Protein Chapter 3.

Vitamin Classifications Based on Solubility—(cont.)

Vitamin Classifications Based on Solubility—(cont.)

• Water-soluble vitamins—(cont.)

– Vitamin B1 2—(cont.)

o Only water-soluble vitamin that does not occur naturally in plants

o Requires an intrinsic factor

o Deficiency symptoms may take 5 to 10 years or longer to develop.

o People with pernicious anemia require parenteral injections of vitamin B1 2.

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Vitamin Classifications Based on Solubility—(cont.)

Vitamin Classifications Based on Solubility—(cont.)

•Water-soluble vitamins—(cont.)

– Vitamin B1 2—(cont.)

o Recommended that people older than 50 years obtain most of their requirement from fortified foods or supplements

– Other B vitamins

o Pantothenic acid

o Biotin

Page 64: Protein Chapter 3 and Vitamins Chapter 5. Protein Chapter 3.

Vitamin Classifications Based on Solubility—(cont.)

Vitamin Classifications Based on Solubility—(cont.)

• Water-soluble vitamins—(cont.)

– Non–B vitamins

o Inositol

o Choline

o Carnitine

Page 65: Protein Chapter 3 and Vitamins Chapter 5. Protein Chapter 3.

Vitamin Classifications Based on Solubility—(cont.)

Vitamin Classifications Based on Solubility—(cont.)

• Water-soluble vitamins—(cont.)

– Vitamin C

o Ascorbic acid

o Found in citrus fruits and juices

o Prevents scurvy

o Water-soluble antioxidant that protects vitamin A, vitamin E, and PUFA from destruction

Page 66: Protein Chapter 3 and Vitamins Chapter 5. Protein Chapter 3.

Vitamin Classifications Based on Solubility—(cont.)

Vitamin Classifications Based on Solubility—(cont.)

• Water-soluble vitamins—(cont.)– Vitamin C—(cont.)

o No clear and convincing evidence that large doses of vitamin C prevent colds.

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Vitamins in Health Promotion—(cont.)Vitamins in Health Promotion—(cont.)

• What about supplements?

– People who choose to take an all-purpose multivitamin should select one that provides 100% of the daily value (DV) for vitamins with an established DV.

– The USP stamp ensures the quality of supplements but not the safety or benefits.

– High-cost supplements are not necessarily superior to lower cost ones.

Page 68: Protein Chapter 3 and Vitamins Chapter 5. Protein Chapter 3.

Vitamins in Health Promotion—(cont.)Vitamins in Health Promotion—(cont.)

• Can supplements be used as insurance against poor food choices?

– Supplements are not substitutes for healthy food: “supplement” means “add to,” not “replace.”

– Supplements indicated only when diet cannot provide enough vitamin or there is a digestion, absorption or metabolism not allowing WWFQ for a particular vitamin(s)

• A word of caution

– Supplements taken to augment a dietary intake that is already adequate are unnecessary and expensive with no benefit