Water Soluble Vitamins
By Jennifer Turley and Joan Thompson
© 2016 Cengage
Presentation Overview
• Explore chemistry, functions, deficiency,
adequacy, toxicity, and food sources of the
water soluble vitamins: thiamin, riboflavin,
niacin, B6, B12, folate, vitamin C,
panthothenic acid, biotin, and choline.
Thiamin: B1
Chemistry & Functions
• Enzyme cofactor in energy metabolism:
Carbohydrate & BCAA.
– B1 functions as the active group of thiamin pyrophosphate (TPP).
• Supports normal appetite & nervous system
function.
ATP Energy Production
Thiamin: B1
Deficiency & Toxicity
Deficiency
Adequacy
(<66% of DRI)
DRI: 1.1-1.2 mg/day
Approx. <0.8 mg/day
RDI: 1.5 mg
Beriberi (wet and dry)
Normal energy
Cardio-Vascular: Heart rhythm changes
(Glucose & BCAA)
Central Nervous System: Mental changes,
metabolism. Normal
confusion, amnesia, disturbed eye movement
appetite and nervous
GI System: Nausea, anorexia
system functioning.
Neuro-Muscular: Muscle weakness, tingling hands
and feet
peripheral paralysis, decreased ability to
coordinate motor movement, disturbed gait
Other: Edema, exhaustion, weight loss
Toxicity is poorly documented in humans
(UL is Not Established)
DRI is based upon 0.5 mg
B1 per 1,000 Calories
Adult DRI values
Thiamin: B1
Food Sources
• Pork
• Whole grains
• Enriched bread and
cereal products
It is added back by law to
processed grains
Thiamin in Foods
Adult DRI: 1.1-1.2 mg/day
Riboflavin: B2
Chemistry & Functions
• Enzyme cofactor in energy metabolism: fatty
acid oxidation.
– B2 functions as the active group of two coenzymes flavin
mononucleotide (FMN) and flavin adenine dinucleotide
(FAD).
Riboflavin: B2
Deficiency & Toxicity
Deficiency
Adequacy
(<66% of DRI)
DRI: 1.1-1.3 mg/day
Approx. <0.85 mg/day
RDI: 1.7 mg
Ariboflavinosis
Normal fatty acid metabolism
Bone & tooth: Halts growth
GI System: Sore and swollen throat,
swollen magenta colored tongue,
cracking at the corners of the mouth
Skin: Dandruff
DRI is based upon 0.6
mg B2 per 1,000
Calories
Adult DRI values
Toxicity is poorly documented in humans
(UL is Not Established)
Riboflavin: B2
Food Sources
• Milk products
• Organ meats
• Whole and enriched grains and
products such as bread, cereal,
and pasta
It is added back by law
into processed grains
Riboflavin in Foods
Adult DRI: 1.1-1.3 mg/day
Niacin: B3
Chemistry & Functions
1 niacin equivalent (NE) = 1 mg nicotinic acid.
60 mg tryptophan can produce 1 NE.
• Enzyme cofactor in energy metabolism:
amino acids, fatty acids, and glucose
– A part of nicotinamide adenine dinucleotide (NAD)
and nicotinamide adenine dinucleotide phosphate
(NADP).
– Supports steroid synthesis, health of the skin,
nervous system, and digestive system.
Niacin: B3
Deficiency & Toxicity
Deficiency
Adequacy
Toxicity
(<66% of DRI)
DRI: 14-16 mg/day
(>UL)
Approx. <9-11 mg/day
RDI: 20 mg
>35 mg/day
Pellegra
Normal energy
Central Nervous System:
metabolism & steroid
Depression, apathy, headache, synthesis.
dementia (including memory
DRI is based upon
loss).
6.6 mg B3 per 1,000
GI System: Bright red tongue,
Calories
diarrhea (GI disturbances of
vomiting, diarrhea, and
constipation)
Adult deficient,
Skin: Dermatitis
adequate, toxic
Other: Fatigue
values
Not from food but rather
nicotinic acid
supplements
Cardio-Vascular: Violent
flushing reaction from
vasodilation
Central Nervous
System: Blurred vision
GI System: Nausea,
vomiting, liver toxicity
Niacin: B3 Food Sources
• Meats, fish, poultry
• Whole & enriched grains
& products
• Bread, cereal, & pasta
• Dairy products & legumes
are good sources of
tryptophan
It is added back by
law into processed
grains
Niacin in Foods
Adult DRI: 14-16 mg/day
Vitamin B6
Chemistry & Functions
• B6 forms (PN, PL, PM, PNP, PLP, PMP) are coenzymes in
the metabolism of amino acids, glycogen, and some lipids.
• Interconversion of amino acids (AA) to carbohydrate or
carbohydrate to nonessential AA.
– Removal of N from AA: “deamination” & "transamination"
• Needed for heme synthesis & conversion of tryptophan to
niacin.
Vitamin B6
Deficiency & Toxicity
Deficiency
Adequacy
Toxicity
(<66% of DRI)
DRI: 1.3 mg/day
(>UL)
Approx. <0.85 mg/day
RDI: 2 mg
>100 mg/day
Normal metabolism
of amino acids,
glycogen, and some
lipids. Normal heme
synthesis &
conversion of
tryptophan to niacin.
Not from food but rather
large supplement doses
Cardio-Vascular:
Microcytic anemia
Central Nervous System:
confusion, depression,
epileptic convulsions
Skin: Seborrheic (greasy)
dermatitis
DRI is based upon 0.016 mg of B6 per
gm pro consumed
Neuro-Muscular: Nerve
damage, sensory
neuropathy, tingly to
numb hands and feet
Skin: Dermatological
lesions
Adult deficient, adequate, toxic values
Vitamin B6
Food Sources
•
•
•
•
•
Meats, Fish, Poultry
Fortified cereals
Legumes
Non-starchy vegetables
Non-citrus fruits
Vitamin B6 in Foods
Adult DRI: 1.3 mg/day
Vitamin B12
Chemistry & Functions
• Required for nucleic acid, red blood
cell & other new cell synthesis.
• Important for nerve cell maintenance.
• Cofactor in energy fatty acids & amino
acids metabolism
• Conversion of homocysteine to
methionine.
• Synergizes with folic acid.
Vitamin B12
Interesting Facts
• Needs intrinsic factor (a protein produced in
the stomach) and gastric acid.
• Is absorbed in the ileum.
• If the GI tract is not healthy, B12 must be
given by intramuscular injection.
• Nasal spray B12 supplements are available.
• With high dietary intakes, the excess can
be stored accumulatively in the liver.
Vitamin B12
Deficiency & Toxicity
Deficiency
Adequacy
(<66% of DRI)
DRI: 2.4 µg/day
Approx. <0.85 µg/day
RDI: 6 µg/day
Pernicious anemia.
Normal synthesis of
Macrocytic normochromic anemia, compounded with nucleic acids and new
cells, nerve cell
nerve damage.
maintenance, fatty acid
Central Nervous System: Loss of concentration,
and amino acid
memory loss, disorientation, dementia, visual
metabolism, and
disturbances
GI System: Impaired bowel (increased gas production homocysteine
catabolism.
& constipation), sore tongue & loss of appetite
Neuro-Muscular: Nerve damage, gait disturbances,
Normal synergy with
tingling & numbness in the hands & feet
folate
Other: Insomnia, impotency, reduced bladder control
Toxicity is poorly documented in humans
(UL is Not Established)
Adult deficient, adequate values
Vitamin B12
Food Sources
• Animal food sources: eggs,
milk, cheese, meats.
• Since it is commonly found
in animal products, vegans
need to supplement this
nutrient.
Vitamin B12 in Foods
Adult DRI: 2.4 µg/day
Folate, Folic Acid
Chemistry & Functions
•
•
•
•
Nucleic acid synthesis, new cell synthesis
Cofactor in amino acid metabolism
Conversion of homocysteine to methionine
Synergizes with B12
Folate
Deficiency & Toxicity
Deficiency
Adequacy
(<66% of DRI)
DRI: 400 µg/day
Approx. <260 µg/day
RDI: 400 µg/day
Cardio-Vascular: Macrocytic normochromic anemia, Normal nucleic acid synthesis,
heart palpitations, shortness of breath
new cell formation, amino acid
metabolism, conversion of
Central Nervous System: Weakness, fatigue,
homocysteine to methionine,
decreased concentration, irritability, headache
synergy with B12.
GI System: Red tongue
Hyperhomocysteinemia (heart disease risk)
In utero deficiency can cause Spina Bifida.
Toxicity is poorly documented in
humans
(UL is >1000 µg/day)
Adult deficient, adequate, toxic values
Folate
Food Sources
• Raw leafy green vegetables & green
vegetables
• Legumes, oranges, liver, brewer’s yeast,
wheat germ, and some fortified cereals
Folate in Foods
Adult DRI: 400 µg/day
Vitamin C
Chemistry & Functions
• Required for collagen synthesis needed in
skin, bones, teeth, blood, epithelial tissue,
tendons & ligaments.
• Cofactor for carnitine & neurotransmitter
synthesis.
• Water soluble antioxidant
• Increases absorption of non-heme iron
Vitamin C
Deficiency & Toxicity
Deficiency
Adequacy
Toxicity
(<66% of DRI)
DRI: 75-90 mg/day
(>UL)
Approx. <50-60 mg/day
RDI: 60 mg/day
>2000 mg/day
Scurvy
Central Nervous System:
Weakness, fatigue, depression
Normal collagen
synthesis & connective
tissue formation.
GI System:
Gastrointestinal
disturbances especially
diarrhea
GI System: Swollen red bleeding
Normal carnitine,
gums
Other: Increased risk for
neurotransmitter, and
kidney stones and iron
water soluble antioxidant
Skin: Follicular hyperkeratosis,
toxicity only in certain
function
petechia, easy bruising, impaired
people
wound healing
Other: Joint pain, edema, coiled
hairs
Adult deficient, adequate, toxic values
Smokers need +35 mg/day
Vitamin C
Food Sources
• Citrus fruits, berries, kiwi, and melons
• Cabbage family vegetables, peppers,
• Vitamin C fortified foods
Vitamin C in Foods
Adult DRI: 75-90 mg/day
Pantothenic Acid
Chemistry, Functions, & Food Sources
• Essential component in Coenzyme A which is
involved in metabolism of fatty acids, cholesterol,
steroid hormones, vitamins A and D,
neurotransmitters, amino acids, & porphyrin &
corrin rings.
Pantothenic Acid
Deficiency & Toxicity
Deficiency
Adequacy
(<66% of DRI)
DRI: 5 mg/day
Approx. <3.3 mg/day
Central Nervous System: Fatigue, apathy,
irritability, restlessness
Normal coenzyme A activity &
metabolism of fatty acid, cholesterol,
steroid hormones, vitamins A and D,
GI System: Nausea, vomiting, abdominal cramps neurotransmitters, amino acids, and
porphyrin and corrin rings
Neuro-Musccular: Muscle cramps, impaired gait
Other: Burning feet, sleep disturbances,
hypoglycemia, and increased insulin sensitivity
Toxicity is poorly documented in humans
(UL is Not Established)
Adult deficient, adequate values
Pantothenic Acid in Foods
Widely distributed in food, highest in high protein animal products,
yeast, legumes, and whole grains
Adult DRI: 5 mg/day
Biotin
Chemistry, Functions, & Food Sources
• Coenzyme in carboxylation reactions in energy
metabolism.
• Cell proliferation, gene silencing, & DNA repair.
• Widespread in foods, highest in high protein animal
products, yeast, legumes, nuts, whole grains, &
chocolate.
• Small amounts made by intestinal bacteria.
Quantitative data unavailable
for graphical analysis
Biotin
Deficiency & Toxicity
Deficiency
Adequacy
(<66% of DRI)
DRI: 30 µg/day
Approx. <3.3 mg/day
Central Nervous System: Lethargy,
depression, hallucinations, weakness,
fatigue
Normal energy metabolism,
cell proliferation, gene
silencing, and DNA repair
Neuro-Muscular: Muscle pain
Skin: Scaly red rash around the eyes,
nose and mouth
Other: Conjunctivitis, hair loss
Toxicity is poorly documented in
humans
Adult deficient, adequate, toxic values
(UL is Not Established)
Choline
Chemistry & Functions
• Is a component of the neurotransmitter acetylcholine, thus
plays a role in memory and muscle control.
• Is in the phospholipid, lecithin (phosphatidlycholine) which
is needed to maintain cell membrane stability.
• Needed for lipid and cholesterol transport and
metabolism, component of pulmonary surfactant
• Is in bile acids
Choline
Deficiency & Toxicity
Deficiency
Adequacy
Toxicity
(<66% of DRI)
DRI: 425-550 mg/day
(>UL)
Approx. <280-360
mg/day
>3,500 mg/day
GI System: Fatty liver Normal acetylcholine, cell
and liver damage
membrane stability, bile
acids, lipid and cholesterol
transport and metabolism,
pulmonary surfactant
Cardio-Vascular:
Hypotension
GI System: Altered liver
function, increased
salivation
Other: Fishy body odor
Adult deficient, adequate, toxic values
Choline
Food Sources
• Egg yolk, soy beans, peanuts
• High protein animal products
Quantitative data unavailable
for graphical analysis
Some
Summary Points
• The water soluble vitamins have specific
functions.
• DRIs are established for all essential water
soluble vitamins.
• Deficiency and toxicity sign and symptoms are
established for most of these nutrients.
References for this presentation are
the same as those for this topic found
in module 5 of the textbook