Transcript Vitamin and Mineral Deficiencies and Toxicities

Water Soluble Vitamins
Module 5.2
Water Soluble Vitamins
 An organic* substance-coenzyme and/or regulator of
metabolic processes
 Do not supply calories (energy)
 Vitamins are classified by their biological and chemical activity,
not their structure-made of single units not long chains
• Water soluble consists of the B vitamins and Vitamin C.
• DRIs are established for all essential water soluble vitamins.
• Deficiency and toxicity sign and symptoms are established for
most of these nutrients.
Thiamin: B1
• Thiamin was the first B vitamin to be identified, and is
also called B1.
• Enzyme cofactor in energy metabolism:
• Supports normal appetite & nervous system function.
Deficiencies
• Crucial role in processes involving the nerves. Thiamin
deficiency causes neuropathy through neuron death.
– Impairs nutrient absorption
• Beriberi (wet or dry forms)
• Alcohol interferes with absorption-alcoholics
prone to deficiency
• Wernicke–Korsakoff syndrome form of
wet beriberi
• Ocular disturbances- paralysis of eye
movements
• Changes in mental state (dementia)decline in mental function
• Unsteady abnormal stance and gait
Thiamin: B1
Deficiency & Toxicity
Deficiency
Adequacy
(<66% of DRI)
Approx. <0.8 mg/day
DRI: 1.1-1.2 mg/day
RDI: 1.5 mg
• Beriberi (wet and dry)
• Cardio-Vascular: Heart rhythm changes
• Central Nervous System: Mental changes,
confusion, amnesia, disturbed eye movement
• GI System: Nausea, anorexia
• Neuro-Muscular: Muscle weakness, tingling
hands and feet
• peripheral paralysis, decreased ability to
coordinate motor movement, disturbed gait
• Other: Edema, exhaustion, weight loss
Normal energy
(Glucose & BCAA)
metabolism. Normal
appetite and nervous
system functioning.
DRI is based upon
0.5 mg B1 per 1,000
Calories
Adult DRI values
Toxicity is poorly documented in humans
(UL is Not Established)
Thiamin (B1) in Foods
Food Sources
• Pork
• Whole grains
• Enriched bread and cereal products
• Sunflower seeds
Adult DRI: 1.1-1.2
mg/day
Riboflavin: B2
• Riboflavin a yellow-orange solid substance. Imparts color to vitamin
supplements and yellow color to urine.
• Name "riboflavin" from "ribose" (pentose monosaccharide) and
"flavin", which imparts the yellow color to the oxidized molecule
(from Latin flavus, "yellow").
• Riboflavin is easily destroyed by heat and exposure to light.
Ultraviolet rays or fluorescent lamps destroy. Riboflavin in milk
easily destroyed by ultraviolet rays. For this reason milk was
placed in opaque containers.
1. Important component in the citric acid cycle and assists the body
with the absorption of other vitamins.
2. Enzyme cofactor in fatty acid oxidation & amino acids breakdown.
3. B2 functions as the active group of two coenzymes flavin
mononucleotide (FMN) and flavin adenine dinucleotide (FAD).
• FAD- flavin adenine dinucleotide- electron carrier for energy
• FAD is required to convert retinol (vitamin A) to retinoic acid
• FAD required for synthesis of an active form of folate (B9)
• FAD necessary for conversion of tryptophan to niacin (B3)
Riboflavin: B2
Deficiency & Toxicity
Deficiency
Adequacy
(<66% of DRI)
Approx. <0.85 mg/day
DRI: 1.1-1.3 mg/day
RDI: 1.7 mg
• Ariboflavinosis
• Bone & tooth: Halts growth
• GI System: Sore and swollen
throat, swollen magenta
colored tongue, cracking at the
corners of the mouth
• Skin: Dandruff
Normal fatty acid
metabolism
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 in Foods
Food Sources
• Dairy products are a good source of riboflavin.
• Whole and enriched grains and products such as bread, cereal,
and pasta (It is added back by law into processed grains)
• Plant sources of riboflavin include mushrooms, broccoli,
asparagus, whole grains and green, leafy vegetables.
• Animal sources include organ meats red meat, poultry and fish.
Adult DRI: 1.11.3 mg/day
Niacin: B3
• Niacin is added to enriched flours in North America.
• Enzyme cofactor in energy metabolism: amino acids, fatty acids,
and glucose (Coenzyme vital to obtaining energy - NAD)
• Two forms of niacin are nicotinic acid and nicotinamide.
• A part of nicotinamide adenine dinucleotide (NAD) and
nicotinamide adenine dinucleotide phosphate (NADP).
• Can be made from the essential amino acid tryptophan.
Requires B6 for conversion. FAD (from riboflavin) is required
to convert tryptophan to niacin
• Maize binds niacin and tryptophan preventing them from being
utilized- maize treated with lime inhibits its binding capacity
• Niacin has been used to help lower cholesterol
• Deficiency results in pellagra
– 3 D’s: dermatitis, diarrhea and dementia
• Overuse of supplements can result in elevated BP, cardiac
arrhythmias, nausea, vomiting, elevated blood sugar and impaired
liver function.
• Supports steroid synthesis, health of the skin, nervous system,
and digestive system.
pellagra
Niacin: B3
Deficiency & Toxicity
Deficiency
Adequacy
Toxicity
(<66% of DRI)
Approx. <9-11 mg/day
DRI: 14-16 mg/day
RDI: 20 mg
(>UL)
>35 mg/day
Normal energy
metabolism &
steroid synthesis.
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
Pellegra
• Central Nervous
System: Depression,
apathy, headache,
dementia (including
memory loss).
• GI System: Bright red
tongue, diarrhea (GI
disturbances of vomiting,
diarrhea, and
constipation)
• Skin: Dermatitis
• Other: Fatigue
DRI is based upon
6.6 mg B3 per 1,000
Calories
Adult deficient,
adequate, toxic values
Niacin B3 in Foods
Adult DRI: 1416 mg/day
•
•
•
•
Milk
Eggs
It is added back by law
Meats, Fish (tuna, halibut), Poultry
into processed grains
Whole & enriched grains & products
• Bread, cereal, & pasta
• Dairy products & legumes are good sources of tryptophan
Vitamin B6
• B6 forms (PN (pyridoxine-supplements), PL, PM, PNP, PLP
(metabolic active form), PMP) coenzymes necessary for amino
acid and fatty acid metabolism, converts glycogen to glucose
Without sufficient B6 all amino acids would become essential.
• Interconversion of amino acids (AA) to carbohydrate or
carbohydrate to nonessential AA.
– Removal of N from AA: “deamination” & "transamination"
transfer of AA to another substance
• Converted into pyridoxal phosphate (PLP), required for many
enzyme reactions in the body
 PLP important role neurotransmitter synthesis: serotonin,
dopamine, epinephrine, norepinephrine,
 PLP Improves the ability of hemoglobin to bind O2
• Needed for heme synthesis & conversion of tryptophan to niacin.
• Critical for the conversion of homocysteine back into cysteine
• Used to treat nausea /vomiting in early pregnancy for decades
Vitamin B6
• Homocysteine a non-protein αamino acid. It is homologous to the
amino acid cysteine.
• Biosynthesized from methionine
homocysteine can be recycled into
methionine or converted into cysteine
with the aid of certain B-vitamins.
• Vitamin B6 converts homocysteine
into cysteine.
Removal of N from AA
• Hyperhomocysteinemia
puts one at a higher risk
for coronary artery
disease: atherosclerosis
(hardening of the
arteries)
Vitamin B6
Deficiency & Toxicity
Deficiency
Adequacy
Toxicity
(<66% of DRI)
Approx. <0.85 mg/day
DRI: 1.3 mg/day
RDI: 2 mg
(>UL)
>100 mg/day
• Cardio-Vascular:
Microcytic anemia,
weakness,
• Central Nervous
System: confusion,
depression, epileptic
convulsions insomnia,
irritability
• Skin: Seborrheic
(greasy) dermatitis
Normal metabolism Not from food but rather
of amino acids,
large supplement doses
glycogen, and some • Neuro-Muscular:
lipids. Normal heme
Nerve damage,
synthesis &
sensory neuropathy,
conversion of
tingly to numb hands
tryptophan to niacin.
and feet
• Skin:
Dermatological
lesions
DRI is based upon 0.016 mg of B6 per gm pro consumed
Adult deficient, adequate, toxic values
Vitamin B6 in Foods
Adult DRI: 1.3 mg/day
Food Sources
• Meats, Fish Poultry
• Fortified cereals
• Non-starchy vegetables
• Nuts
• Legumes
• Non-citrus fruits (bananas)
• Contains the mineral cobalt
• Required for nucleic acid, red blood
cell & other new cell synthesis.
• Maintains myelin sheaths that protect nerve fibers; Important
for nerve cell maintenance.
• Cofactor in energy fatty acids & amino acids metabolism
• Conversion of homocysteine to methionine.
• Required for normal functioning of brain and nervous system,
necessary for absorption of iron
• Absorption requires intrinsic factor;
absorbed in the ileum; Secreted through the feces
• Deficiency caused by pernicious anemia (form of megablastic
anemia)
Those at risk of deficiency
strict vegetarians; genetic defect - can’t make intrinsic
factor; elderly who develop atrophic gastritis
• Needs intrinsic factor
(protein produced in the
stomach) and gastric
acid.
• 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.
Absorption of B12
Vitamin B12
Deficiency & Toxicity
Deficiency
Adequacy
(<66% of DRI)
Approx. <0.85 µg/day
DRI: 2.4 µg/day
Pernicious anemia.
• Macrocytic normochromic anemia, compounded
with nerve damage.
• Central Nervous System: Loss of concentration,
memory loss, disorientation, dementia, visual
disturbances
• GI System: Impaired bowel (increased gas
production & constipation), sore tongue & loss of
appetite
• Neuro-Muscular: Nerve damage, gait disturbances,
tingling & numbness in the hands & feet
• Other: Insomnia, impotency, reduced bladder control
Normal synthesis of
nucleic acids and new
cells, nerve cell
maintenance, fatty
acid and amino acid
metabolism, and
homocysteine
catabolism.
Normal synergy with
folate
RDI: 6 µg/day
Toxicity is poorly documented in humans
(UL is Not Established)
Adult deficient, adequate values
Vitamin B12 in Foods
Adult DRI: 2.4 µg/day
Food Sources
• Bacteria in animals synthesize B12; certain types of molds in soil
that animals ingest while grazing.
• Animal food sources: eggs, milk, cheese, meats. chicken,
• Since it is commonly found in animal products, vegans need to
supplement this nutrient.
Folate, Folic Acid (B9)
• Coenzyme in amino acid metabolism
• DNA & red blood cells synthesis (RBC)
• Production and maintenance of new cells.
 Crucial role in pregnancy; ↓ risk of neural tube
defect (spina bifida)
 Requirements- childbearing 400 μg / Pregnancy: 600 μg
• Conversion of homocysteine to methionine
• Deficiency leads to misshapen RBCs; megaloblastic anemia large immature RBCs unable to carry sufficient oxygen.
• Folate can mask a B12
deficiency. Folate and B12
can both create megablastic
anemia. Failure to treat a
B12 deficiency can increase
risk of permanent nerve
damage
Folate (B9)
Deficiency & Toxicity
Deficiency
Adequacy
(<66% of DRI)
Approx. <260 µg/day
DRI: 400 µg/day
• Cardio-Vascular: Macrocytic
normochromic anemia, heart
palpitations, shortness of breath
• Central Nervous System:
Weakness, fatigue, decreased
concentration, irritability, headache
• GI System: Red tongue
Normal nucleic acid
synthesis, new cell formation,
amino acid metabolism,
conversion of homocysteine
to methionine, synergy with
B12.
RDI: 400 µg/day
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 (B9) in Foods
Adult DRI: 400 µg/day
Food Sources
• Raw leafy green vegetables & green vegetables (asparagus,
broccoli)
• Legumes, black-eyed peas, lentils, oranges, liver, brewer’s
yeast, wheat germ, and some fortified cereals
Pantothenic Acid (B5)
• Essential component in Coenzyme A used in formation of
acetyl-CoA.
• Acetyl-CoA critical for metabolism of fatty acids, cholesterol,
steroid hormones, vitamins A and D, neurotransmitters, amino
acids, & porphyrin & corrin rings.
• Little risk of deficiency with a varied
diet. From Greek pantothen
meaning "from everywhere“.
Small amounts found in most foods.
• The major food sources of
pantothenic acid are meats, milk.
Some vegetables are also good
sources, as well as whole grains.
Pantothenic Acid (B5)
Deficiency & Toxicity
Deficiency
Adequacy
(<66% of DRI)
Approx. <3.3 mg/day
DRI: 5 mg/day
• Central Nervous System: Fatigue,
apathy, irritability, restlessness
• GI System: Nausea, vomiting,
abdominal cramps
• Neuro-Musccular: Muscle cramps,
impaired gait
• Other: Burning feet, sleep
disturbances, hypoglycemia, and
increased insulin sensitivity
Normal coenzyme A activity &
metabolism of fatty acid,
cholesterol, steroid hormones,
vitamins A and D,
neurotransmitters, amino
acids, and porphyrin and
corrin rings
Toxicity is poorly documented in humans
Adult deficient, adequate values
(UL is Not Established)
Pantothenic Acid (B5) in Foods
Widely distributed in food, highest in high protein animal
products, yeast, legumes, and whole grains. Also avocados.
Adult DRI: 5 mg/day
Biotin (B7)
• Cofactor in the metabolism of fatty acids and the amino acid
leucine.
• Required for cell growth, synthesis and repair of DNA, gene
silencing and maintenance of blood glucose levels.
• Small amounts made by intestinal bacteria.
– Preliminary studies indicate may aid those with type 2
diabetes for blood sugar level control
• Biotin recommended for strengthening hair and nails
• Deficiency: Caused by raw egg whites (protein - avidin)
binds biotin and prevents absorption. If avidin is cooked it
is denatured and destroyed and biotin can be absorbed.
• Widespread in foods, highest in high protein animal
products, yeast, legumes, nuts, whole grains, EGG YOLK &
chocolate.
Biotin (B7)
Deficiency & Toxicity
Deficiency
Adequacy
(<66% of DRI)
Approx. <3.3 mg/day
DRI: 30 µg/day
• Central Nervous System:
Lethargy, depression,
hallucinations, weakness,
fatigue
• Neuro-Muscular: Muscle pain
• Skin: Scaly red rash around
the eyes, nose and mouth
• Other: Conjunctivitis, hair loss
Normal energy
metabolism, cell
proliferation, gene
silencing, and DNA
repair
Toxicity is poorly documented in humans
(UL is Not Established)
Adult deficient, adequate, toxic values
Vitamin C
• Production and maintenance of collagen.
– Required for collagen synthesis needed in skin, bones, teeth,
blood, epithelial tissue, cartilage, tendons & ligaments.
• Cofactor for carnitine & neurotransmitter synthesis.
• Combats stress-helps release stress hormones
• Increases absorption of non-heme iron
• Vitamin C in foods can be destroyed by oxygen, light and heat, as
well as through contact with copper or iron cookware
• Boosts immunity-fights infection
• Acts as a blood thinner in lieu of aspirin
• Scavenger of environmental pollutants
– Smoking- destroys cells
• Antioxidant –decreases free radicals
• Deficiency – infants, children, elderly
– Scurvy – Scottish surgeon in the Royal Navy, James Lind, first
proved it could be treated with citrus fruit in experiments he
described in his 1753 book A Treatise of the Scurvy. Initially tried
using limes without success. Would be 40 years before treatment
became widespread.
Vitamin C
Deficiency & Toxicity
Deficiency
Adequacy
Toxicity
(<66% of DRI)
Approx. <50-60 mg/day
DRI: 75-90 mg/day
(>UL)
>2000 mg/day
• Scurvy
• Central Nervous
System: Weakness,
fatigue, depression
• GI System: Swollen red
bleeding gums
• Skin: Follicular
hyperkeratosis, petechia,
easy bruising, impaired
wound healing
• Other: Joint pain,
edema, coiled hairs
Normal collagen
synthesis &
connective tissue
formation.
Normal carnitine,
neurotransmitter,
and water soluble
antioxidant function
RDI: 60 mg/day
GI System:
Gastrointestinal
disturbances
especially diarrhea
Other: Increased
risk for kidney
stones and iron
toxicity only in
certain people
Adult deficient, adequate,
toxic values
Smokers need +35 mg/day
Vitamin C in Foods
• Citrus fruits, berries, kiwi, papaya, cantaloupe,
orange, and melons
• Cabbage family vegetables, peppers,
• Vitamin C fortified foods
Adult DRI: 75-90 mg/day
Choline
 Water-soluble substance
 Nonessential nutrient used by the body to synthesize
compounds
• Necessary for synthesis of prominent muscle
neurotransmitter acetylcholine, thus plays a role in memory
and muscle control.
• Required for the synthesis of the phospholipid, lecithin
(phosphatidlycholine) needed to maintain cell membrane
stability.
• Utilized for lipid and cholesterol transport and metabolism
• Component of pulmonary surfactant- deficiency would
lead to collapse of alveolar cells and result in respiratory
failure
• Component of bile acids necessary for fat digestion
• Choline can be synthesized from the amino acid methionine.
• Deficiencies are rare.
Choline
Deficiency & Toxicity
Adult deficient, adequate, toxic values
Deficiency
Adequacy
Toxicity
(<66% of DRI)
Approx. <280-360
mg/day
DRI: 425-550 mg/day
(>UL)
>3,500 mg/day
GI System:
Fatty liver and
liver damage
Normal acetylcholine,
cell membrane
stability, bile acids,
lipid and cholesterol
transport and
metabolism,
pulmonary surfactant
Food Sources
• Egg yolk, soy beans, peanuts
• High protein animal products
Cardio-Vascular:
Hypotension
GI System: Altered
liver function,
increased salivation
Other: Fishy body
odor