 Dissolve in water
 Easily destroyed or washed out during food storage and preparation.
 Are easily absorbed and excreted
 Not stored in the body tissues and must be replaced each day.
 Seldom reach toxic levels

Overview of Water-Soluble Vitamins
 Many B-complex vitamins needed for energy metabolism and form an integral part of coenzymes
 Help the body metabolize CHO, lipids and amino acids



Thiamin pyrophosphate – TPP ( thiamin )
Flavin Adenine Dinucleotide (FAD), Flavin Mononucleotide
(FMN)( riboflavin )
Nicotinamide Adenine Dinucleotide (NAD), Nicotinamide adenine dinucleotide phosphate (NADP)( niacin )
 Coenzyme A ( pantothenic acid )
 Pyridoxal phosphate (PLP) ( Vitamin B-6 )
 Tetrahydrofolic acid ( folate )
 Cofactor ( biotin )

 Many nutrients lost through milling process of grains
 Grain/cereal products are enriched with
 Thiamin, riboflavin, niacin, folate, iron
 Enriched grains still deficient in B-6, magnesium and zinc
 Whole grains contain original nutrients

Distinction between water-soluble and fat-soluble vitamins
Fat-soluble vitamins Water-soluble vitamins
Absorption
Transport
Lymph first, then the blood Direct absorption into the blood
Protein carriers used by many Freely transported
Requireme nts
Periodic doses required
Storage
Excretion
Toxicity
Stored in cells associated with fat
Less readily excreted, tend to remain in fat-storage sites
Toxic levels likely when consuming supplements
Frequent doses required
Circulate in waterfilled parts of the body
Excreted in urine by kidneys
Toxic levels possible when consuming supplements

 Functions as a coenzyme: Thiamin pyrophosphate
(TPP)
 In metabolism of CHO; & amino acids
 Decarboxylation of alpha keto acids (page 227)
 Enzyme is Transketolase: coverts glucose to a 5carbon sugar

 Wide variety of food
 White bread, pork, hot dogs, luncheon meat, cold cereal
 Enriched grains/ whole grains

 1.1 mg/day for women
 1.2 mg/day for men
 Most exceed RDA in diet
 Surplus is rapidly lost in urine; non toxic




Beriberi

 first observed in the Far East where polished rice replaced rice where bran remained intact
.
characterized by
 loss of sensation in the hands and feet, muscular weakness, advancing paralysis,and abnormal heart action.
 Peripheral neuropathy
Dry beriberi
 Weakness, nerve degeneration, irritability, poor arm/leg coordination, loss of nerve transmission
Wet beriberi
 Edema, enlarge heart, heart failure

 Mainly in alcoholics
 Alcohol diminishes thiamin absorption
 Alcohol increases thiamin excretion
 Poor quality diet
 Involuntary eye movement; double vision
 Ataxia: staggering, poor muscle coordination

Mental confusion, “drunken stupor”

 Coenzymes:
 Flavin mononucleotide ( FMN )
 Flavin adenine dinucleotide ( FAD )
 Oxidation-reduction reactions
 Electron transport chain
 Citric Acid Cycle
 Catabolism of fatty acids: beta oxidation
 FMN shuttles hydrogen ions and electrons to into the electron transport chain

 Milk/products
 Enriched grains
 Liver
 Oyster

Brewer’s yeast
 Sensitive to uv radiation (sunlight)
 Stored in paper, opaque plastic containers

 1.1 mg/day for women
 1.3 mg/day for men
 Average intake is above RDA
 Toxicity not documented

 Ariboflavinosis
 Glossitis, cheilosis, seborrheic dermatitis, stomatitis, eye disorder, throat disorder, nervous system disorder

 Nicotinic acid (niacin) & nicotinamide
(niacinamide)
 Coenzyme
 Nicotinamide adenine dinucleotide ( NAD )
 Nicotinamide adenine dinucleotide phosphate
( NADP )
 Oxidation-reduction reaction

 Mushroom
 Enriched grains
 Beef, chicken, turkey, fish, eggs,milk
 Amino acid tryptophan can be converted to niacin
 Heat stable; little cooking loss
 60mg tryptophan can be converted into 1 mg niacin
 Estimate by dividing the total gram of protein by
6

 Pellagra
 3 Ds: Dermatitis, dementia, diarrhea
 appeared in Europe in early 1700s when corn became staple food
 corn lacks niacin and tryptophan

 75-100 x RDA can lower LDL and increase HDL
 Slow/ reverse progression of atherosclerosis with diet and exercise
 Toxicity effects
 Flushing of skin, itching, nausea, liver damage






How are water-soluble vitamins different from fatsoluble vitamins?
Many of the B vitamins all function as a coenzyme, what is a coenzyme?
What disease is associated with a deficiency of niacin?
What disease is associated with a deficiency of thiamin?
What is the Enrichment Act? What nutrients are involved?

 Part of Coenzyme-A
 Essential for metabolism of CHO, fat, protein
Glucose
Fatty acids AcetylCoA
Alcohol
Amino Acids

 Meat
 Milk
 Mushroom
 Liver
 Peanut
 Adequate Intake = 5 mg/day
 Average intake meets AI

 Free and bound form
 Biocytin (protein bound form)
 Freed by Biotinidase in small intestine
 Infant with genetic defect : low levels of biotinidase
 Metabolism of CHO, fat, protein (C skeleton)
 DNA synthesis

 Required to convert pyruvate to oxaloacetate
(TCA cycle) and thus ATP production.
 Required for fatty acid synthesis
 Breaks down leucine
 Sources
 Widely distributed in foods and is produced by intestinal bacteria
 Liver, egg yolk , whole grains, cauliflower are good food sources
 Avidin in raw egg whites bind biotin

 Adequate Intake is 30 ug/day for adults
 This may overestimate the amount needed for adults
 No Upper Limit for biotin

 Rare
 High intake of raw egg white diet
 Alcoholics
 Biotinidase deficiency
 Anticonvulsant drug use
 Signs & symptoms: skin rash, hair loss, convulsion, neurological disorders, impaired growth in children

Vitamin B-6 family: Pyridoxal,
Pyridoxine, Pyridoxamine
 Main coenzyme form: pyridoxal phosphate
( PLP )
 Activate enzymes needed for metabolism of
CHO, fat , protein
 Transamination
 Synthesis of hemoglobin and oxygen binding and white blood cells
 Synthesis of neurotransmitters

 Participates in 100+ enzymatic reactions
 Decarboxylation of amino acid (decarboxylase)
 Transamination reaction (transaminase)
 Structural rearrangement of amino acids (racemase)
 Heme synthesis
 CHO metabolism
 Lipid metabolism
 Neurotransmitter Synthesis
 Conversion of tryptophan to niacin

Homocysteine
 From the metabolism of methionine
 Produces toxic effect on arterial walls
(atherosclerosis)
 Metabolized by vitamins B-6, B-12 and folate

 Meat, fish, poultry
 Whole grains (not enriched back)
 Banana
 Spinach
 Avocado
 Potato
 Heat and alkaline sensitive

 1.3 - 1.7 mg/day for adults
 Daily Value set at 2 mg
 Average intake is more than the RDA

 Microcytic hypochromic anemia
 Seborrheic dermatitis
 Convulsion, depression, confusion
 Reduced immune response
 Peripheral nerve damage

Alcohol reduces PLP formation
L -DOPA-medication used to treat
Parkinson’s disease and
Isoniazid-antituberculosis medication
 Reduce blood concentration of PLP
 Need extra vitamin B-6

 PMS
 B-6 to increase the level of serotonin
 Improve depression
 Not a reliable treatment
 Toxicity potential
 Can lead to irreversible nerve damage with > 200 mg/day
 Upper level set at 100 mg/day

 Consists of pteridine group, para-aminobenzoic acid (PABA), and glutamic acid
 Coenzyme form: tetrahydorfolic acid ( THFA )
 Produce many identical deficiency signs and symptoms as vitamin B-12
 Vitamin B-12 is needed to recycle folate coenzyme

 Absorbed in the monoglutamate form with the help of folate conjugase
 Actively absorbed during low to moderate intake
 Passively absorbed during high intake
 Delivered to the liver where it is changed back to the polyglutamate form
 Mostly stored in the liver
 Excreted in the urine and bile
(enterohepatic circulation)

 DNA synthesis
 Transfer of single carbon units
 Synthesis of adenine and guanine
 Anticancer drug methotrexate
 Homocysteine metabolism
 Neurotransmitter formation
 Amino acid metabolism

 Liver
 Fortified breakfast cereals
 Grains, legumes
 Foliage vegetables
 Susceptible to heat, oxidation, ultraviolet light

 400 ug/day for adults
 Daily Value is set at 400 ug
 Dietary folate equivalents (DFE)
 are units to express folate needs throughout life except during child bearing years
 DFE = [(total synthetic folate) x 1.7] + total food folate intake

 Similar signs and symptoms of vitamin B-
12 deficiency
 Pregnant women
 Alcoholics
 Interferes with the enterohepatic circulation of bile/folate

 Spina bifida
 Anencephaly
 Importance of folate before and during pregnancy

 Epilepsy
 Skin, respiratory disorder
 FDA limits nonprescription supplements to
400 ug per tablet for non-pregnant adults
 OTC Prenatal supplement contains 800 ug
 Upper Level for synthetic folate is 1 mg
 Excess can mask vitamin B-12 deficiency

 Cyanocobalamin, methlcobalamin,
5-deoxyadenosylcobalamin
 Contains cobalt




Folate metabolism
Synthesized exclusively by bacteria, fungi, and algae
Maintenance of the myelin sheaths
Rearrange 3-carbon chain fatty acids so can enter the Citric Acid Cycle

 Many factors can disrupt this process
 Monthly injections of vitamin B-12
 Vitamin B-12 nasal gel
 Megadoses of vitamin B-12 to allow for passive diffusion

 Synthesized by bacteria, fungi and algae
 (Stored primarily in the liver)
 Animal products
 Organ meat
 Seafood
 Eggs
 Hot dogs
 Milk

 2.4 ug/ day for adults and elderly adults
 Average intake exceeds RDA
 B-12 stored in the liver; little is lost
 Non-toxic

 Helps convert methylmalonyl CoA to succinyl CoA (citric acid cycle)
 Recycles folate coenzymes
 Nerve functions
 Maintains myelin sheath
 Megalobalstic anemia

 Pernicious anemia
 Nerve degeneration, weakness
 Tingling/numbness in the extremities
(parasthesia)
 Paralysis and death
 Looks like folate deficiency
 Usually due to decreased absorption ability
 Achlorhydria, especially in elderly

 Absorbed from the small intestine
 All tissues contain choline
 Excess choline is converted to betaine

 Precursor for acetylecholine (neurotransmitter)
 Precursor for phospholipids (such as lecithin)
 Involved in the export of VLDL from the liver
 Precursor for the methyl donor betaine
 Assist in the conversion of homocysteine to methionine

 Widely distributed
 Milk
 Liver
 Eggs
 Peanuts
 Lecithins added to food
 Deficiency rare






Adequate Intake is 550 mg/day for adult males
Adequate Intake is 425 mg/day for adult females
Normal consumption is ~700-1000 mg/day
High doses associated with fishy body odor, vomiting, salivation, sweating, hypotension,
GI effects
Upper Level is set at 3.5 g/day (3500 mg/day)

 Decrease choline stores
 Liver damage (fatty livers)

 Ascorbic acid (reduced form), dehydroascorbic acid (oxidized form)
 Synthesized by most animals (not by human)
 Absorbed by a specific energy dependant transport system
 Passive transport if intake is high
 Decrease absorption with high intakes
 Excess excreted

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
Reducing agent (antioxidant)
Iron absorption
Synthesis of carnitine, tryptophan to serotonin, thyroxine, cortiscosteroids, aldosterone, cholesterol to bile acids
Immune functions
Synthesis of other compounds
Questionable as to vitamin C’s role as an antioxidant in people

 Citrus fruits
 Potatoes
 Green peppers
 Cauliflower
 Broccoli
 Strawberries
 Romaine lettuce
 Spinach
 Easily lost through cooking
 Sensitive to heat
 Sensitive to iron, copper, oxygen

 90 mg/day for male adults
 75 mg/day for female adults
 +35 mg/day for smokers
 Average intake ~72 mg/day
 Fairly nontoxic (at <1 gm)
 Upper level is 2 gm/day
 Excess intake will not cure the common cold

 Scurvy
 Deficient for 20-40 days
 Fatigue, pinpoint hemorrhages
 Bleeding gums and joints, hemorrhages
 Associated with poverty

 Carnitine
 Inositol
 Taurine
 Lipoic acid
 Synthesized in the body at the expense of amino acids and other nutrients

 Found in meat and dairy products
 Synthesized in the liver from amino acids lysine and methionine
 Transports fatty acids into the mitochondria
 Aids in the removal of excess organic acids

 Myo-inositol
 Found in animal products
 Synthesized from glucose
 Precursors to eicosanoids
 Metabolizes calcium ions
 Metabolism is altered in people with diabetics, multiple sclerosis, kidney failure, certain cancers

 Found only in animal products
 Synthesized from methionine and cysteine
 Associated with the photoreceptor in the eye
 Antioxidant activity in the white blood cell and pulmonary tissue
 CNS function, platelet aggregation, cardiac contraction, insulin action, cell differentiation and growth

 Found in meats, liver, and yeast
 Redox agent
 Needed in reactions in which CO
2 is lost from a substrate
 Regenerates vitamin C and glutathione

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
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Para-aminobenzoic acid (PABA)


Part of folate, but not able to make folate
A part of a B-complex family for bacteria
Laetrile

“Vitamin B-17”
 Contains cyanide, promoted as a cancer cure
Bioflavonoids

“Vitamin P” --no nutritional requirement
Pangamic Acid

“Vitamin B-15” and is illegal

 Many diseases
 Formation of tumors (neoplasms)
 Benign
 Malignant





Carcinomas
 Cells that covers the body, including the secretory organs
Sarcomas
 Connective tissues and bones
Leukemias
 Blood forming tissues
Lymphomas
 Lymph nodes or lymphoid tissues





Protooncogenes
 Genes that cause a resting cell to divide
Tumor Suppressor Genes


Genes that prevent cells from dividing
P53 gene finds error on the DNA and repairs it
Oncogene
 The cancer gene
 A protoonocogene out of control
DNA Repair Mechanism

 Telomeres
 Caps at the ends of chromosomes
 Telomerase
 Enzyme that maintains the length and completeness
 Daughter cells are slightly shorter and telomerase activity decreases
 Cell undergoes apoptosis
 Malignant tumor cells, the telomerase activity increases —the cells can live indefinitely

 Prevents cancer initiation
 In the liver and intestinal cells
 Converts dangerous compounds into harmless water-soluble metabolites

 Exposure to carcinogen
 Alteration of DNA
 Is relatively short

 May last for months or years

Damage is “locked” in
 Cell division increases
 Promoters: estrogen, alcohol, maybe dietary fat
 Decrease time available for repair

 Final stage
 Cancer cells proliferate and form a mass
 Invade surrounding tissue
 Metastasize to other tissues
 Heredity can only explain a small percentage of cancers
 Environment contributes to most cancer

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Excessive intake of calories increases the risk of cancer
Excessive body fat affects sex hormone production
High intake of fruits and vegetables is associated with lower risk
High intake of meats and protein is associated with higher risk
Excessive alcohol increases the risk
Excessive charcoal broiling increases risk
Nitrosamines (from nitrite) increases risk
Mycotoxins (from fungi) increases risk

 The National Academy of Sciences recommends 30% of total calories from fat
 Effects of the type of fat to cancer
 There are still wide gaps in knowledge linking fat and cancer
 Excessive intake is a more likely cause

 Calcium intake is inversely related to cancer
 Calcium binds to bile acids in the colon
 Vitamin D inhibits progression of cancerous polyps
 Vitamin D inhibits rapid colon/rectal cell growth in patients with ulcerative colitis

 Remain physically active
 Avoid obesity
 Engage in physical training that promotes lean muscle mass
 Consume abundance of fruits and vegetables
 Consume plenty of low-fat/nonfat dairy products
 Avoid high intakes of red meat and animal fat
 Avoid excessive alcohol

(CAUTION)


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





Early detection is critical
Unexplained weight loss
A c hange in bowel or bladder habits
A sore that does not heal
U nusual bleeding or discharge
A t hickening or lump in the breast or elsewhere
I ndigestion or difficulty in swallowing
An o bvious change in a wart or a mole
A n agging cough or hoarseness