NS 315Unit 7: Water Soluble Vitamins

Jeanette Andrade MS,RD,LDN,CDE

Kaplan University

ObjectivesObjectives

• What are we going to learn about tonight?– Vitamin C– Vitamin B1– Riboflavin– Niacin– Pantothenic Acid

– Biotin– Folate– Vitamin B12– Vitamin B6

Vitamin CVitamin C• Also known as ascorbic acid• We have to obtain vitamin C through the

diet• RDAs:

– Males 19-70 years old 90 mg/day– Females 19-70 years old 75 mg/day– Smokers males 19+ 125 mg/day– Smokers females 19+ 110 mg/day

• What foods contain Vitamin C?

Functions of Vitamin CFunctions of Vitamin C

• Required for the synthesis of collagen

• Required for the synthesis of neurotransmitter; norepinephrine

• Required for synthesis of carnitine (fat oxidation)

• Effective antioxidant

Deficiency of Vitamin CDeficiency of Vitamin C• The more severe deficiency- scurvy occurs

with lack of vitamin C in the diet

• Scurvy:– Rare in United States, but can occur in

malnourished and alcoholics– Bruising, bleeding gums and dental problems,

anemia and dry hair

http://www.merck.com/mmhe/sec12/ch154/ch154i.html

Toxicity of Vitamin CToxicity of Vitamin C• Up to 2 gm of vitamin C per day causes no

adverse effects

• Most common problems are abdominal pain and osmotic diarrhea (due to unabsorbed vitamin C)

• At risk populations: Renal disease patients, hemochromatosis, thalassemia and sideroblastic anemia patients

Vitamin BVitamin B11• Also known as Thiamin or Aneurine

• Phosphorylated forms: Thiamin monophosphate (TMP), Thiamin triphosphate (TTP), and Thiamin pyrophosphate (TPP)

• RDAs for Thiamin:– Males 19-70 years old 1.2 mg/day– Females 19-70 years old 1.1 mg/day

• What foods contain Thiamin?

Functions of ThiaminFunctions of Thiamin• Coenzyme function as TPP

• Assists in pyruvate dehydrogenase, alpha-ketoglutarate dehydrogenase, and branched-chain ketoacid dehydrogenase

• Coenzyme needed in Pentose Phosphate Pathway, an alternate for glucose oxidation

Thiamin

Some Thiamin Containing Some Thiamin Containing EnzymesEnzymes

http://pubs.niaaa.nih.gov/publications/arh27-2/IMAGES/Page138.gif

Deficiency of ThiaminDeficiency of Thiamin

• Primary deficiency: people consuming white rice or highly refined carbohydrates in developing countries (Beriberi) and alcoholics (Wernicke- Korsakoff Syndrome)

• Secondary deficiency: Increased demand, impaired absorption, impaired metabolism

• 3 common Beriberis:– Dry– Wet– Infantile

http://www.merck.com/mmpe/sec01/ch004/ch004f.html

BeriberiBeriberi• Dry:

– Peripheral neurologic deficits– Effect mainly lower extremities and

with continued deficiency will effect the arms

• Wet (cardiovascular):– Vasodilation, tachycardia and lactic

acidosis– Heart failure develops

• Infantile– Occurs in infants (3-4 weeks old),

breastfed by thiamin deficient mothers– Heart failure- may occur suddenly

http://www.merck.com/mmpe/sec01/ch004/ch004f.html

RiboflavinRiboflavin• 2 coenzyme derivatives:

– Flavin mononucleotide (FMN)– Flavin adenine dinucleotide (FAD)

• RDAs for males 19-70 years: 1.3 mg/day

• RDAs for females 19-70 years: 1.1 mg/day

• What foods contain riboflavin?

Functions of RiboflavinFunctions of Riboflavin• Flavoproteins provide most roles in the

body:– Electron Transport Chain– PDHC– Beta oxidation– Various mineral and vitamin metabolism

Riboflavin

http://www.3dchem.com/molecules.asp?ID=63

Deficiency of RiboflavinDeficiency of Riboflavin

• No clear deficiency, but can occur– Alcoholics– Congenital Heart disease – Some cancers

http://www.wrongdiagnosis.com/phil/html/riboflavin-deficiency/3990.html

Vitamin BVitamin B33: Niacin: Niacin• Water soluble vitamin B3

• Nicotinamide is a derivative of niacin and used to form the coenzymes nicotinamide adenine dinucleotide (NAD) and nicotinamide adenine dinucleotide phosphate (NADP)

• RDAs – Males 19-70 years old 16 mg/day– Females 19-70 years old 14 mg/day

• What foods contain Niacin?

Functions of NiacinFunctions of Niacin

• Oxidation- Reduction Reactions– Krebs or TCA cycle– Glycolysis– Beta oxidation

• Non-redox reactions– Mainly occurring in bacteria

Niacin or Vitamin B3

Deficiency of NiacinDeficiency of Niacin• Usually occurring in

developing countries• Primary deficiency: Pellagra

– Extreme deficiency in both niacin and tryptophan

– Most common physical attributes are dermatitis, diarrhea and dementia

– Can be cured with supplements

• Secondary deficiency: Alcoholism, Diarrhea and Cirrhosis

http://www.merck.com/mmpe/sec01/ch004/ch004d.html

Toxicity of NiacinToxicity of Niacin

• Sometimes used in large amounts to reduce LDL cholesterol and triglyceride levels and to increase HDL cholesterol

• General symptoms are flushing

Pantothenic AcidPantothenic Acid

• Once referred to as Vitamin B5

• No RDAs, but AI or Adequate intake– Males and females >19 years: 5 mg

• What foods is pantothenic acid found in?

Pantothenic AcidPantothenic Acid

• Functions:– Component of CoA– Participates in Cellular Metabolisms:

• Carbohydrate• Protein • Lipid

Pantothenic Acid

http://commons.wikimedia.org/wiki/File:Pantothenic_acid_structure.svg

Deficiency of Pantothenic Deficiency of Pantothenic AcidAcid

• Burning Feet Syndrome

• Malnourished population:– Alcoholism– Diabetes– Inflammatory Bowel Disease

BiotinBiotin

• Also known as vitamin B7

• No RDAs, but Adequate Intake (AI) – Men and women >19 years of age: 30 µg

• What foods contain Biotin?

Functions of BiotinFunctions of Biotin

• Considered a coenzyme with:– Pyruvate Carboxylase– Acetyl CoA carboxylase– Propionyl CoA carboxylase

Biotin

http://www.chm.bris.ac.uk/webprojects2002/schnepp/biotin.html

Deficiency of BiotinDeficiency of Biotin

• Usually occurs when consuming raw eggs in excess amounts

• Gastrointestinal disorders

• Pregnancy

• Genetic defects

http://mark.asci.ncsu.edu/Nutrition/NutritionSlides/38.jpg

FolateFolate• Water soluble B-complex vitamin

• Folic acid is the more stable form and not found in foods or humans, but in supplements and fortified foods

• Folate containing molecules are found in foods and humans

• RDA for folate: – Males and Females 14 years old+ 400 µg/day

• What foods contain folate?

Functions of FolateFunctions of Folate• Reproduction and maintenance of cells

• Needed to make DNA and RNA

• Needed to make red blood cells to prevent anemia in adults and children

http://healthlink.mcw.edu/article/984001430.html

Folic acid

Fig. 9-28, p. 350

FolateFolateDeficiency

• What can happen with folate deficiency?– For pregnant women,

can give birth to low weight, neural tube defect infants

– Infants and children can have slow growth

– What type of anemia may occur with both folate and vitamin B12 deficiency?

Toxicity

• Very uncommon in both foods and supplements due to it is a water soluble vitamin and can be excreted in the urine, but it can happen

Vitamin BVitamin B1212

• Methylcobalamin and 5-deoxyadenosyl cobalamin are the forms of vitamin B12 used in the human body

• RDA for males and females 19-70 years old 2.4 mcg/day

• What foods contain Vitamin B12 ?

Functions of Vitamin BFunctions of Vitamin B1212

• Cofactor for methionine synthase

• Cofactor for L-methylmalonyl-CoA mutase– Cobalamin is the cofactor for this enzyme

Vitamin B12

• Methylcobalamin is required for the function of the folate-dependent enzyme, methionine synthase

• This enzyme is required for the synthesis of methionine from homocysteine

Vitamin BVitamin B1212 Necessary for Folate Necessary for Folate

FunctionFunction

Vitamin BVitamin B1212

Deficiency

• Pernicious anemia• Food bound vitamin

B12 malabsorption• Atrophic gastritis• Who may be more

affected with vitamin B12 deficiency?

Toxicity

• None has been seen with food or supplements even as high as 1000mcg/day

Vitamin BVitamin B66• 3 forms of vitamin B6

– pyridoxal (PL)– pyridoxine (PN)– pyridoxamine (PM)

• The principal coenzyme factor, pyridoxal-5-phosphate (PLP) has the most important function in humans

• Must be obtained from the diet• RDAs for males and females 19-50 years old is

1.3 mg/day

• What foods contain vitamin B6 ?

Functions of Vitamin BFunctions of Vitamin B66

• PLP is the main cofactor in multiple enzyme reactions for humans to function:– Nervous System: Neurotransmitters are synthesized

with PLP- dopamine, serotonin– Red blood cell formation: Synthesis in heme– Niacin Formation: PLP synthesizes tryptophan to niacin– Hormone function: PLP binds to steroid receptors to

inhibit the binding of steroid hormones– Nucleic Acid Synthesis: Coenzyme for mobilization in a

single one carbon metabolism

Vitamin BVitamin B66

Deficiency• Uncommon, unless

you are an alcoholic

Toxicity• Usually when taking

the form of B6 : pyridoxine in supplements over an extended period of time