Transcript The B Vitamins - Hoblitzell`s Science Spot

“The B Vitamins”
Why plural? There are eight.
What do they do?
• Each B vitamin activates a different
enzyme, so they have lots of
different jobs.
• Bs do not supply us with energy.
• “They do help us metabolize carbs,
lipids, and amino acids.”
• So even though they don’t directly
contain energy, they help us get it.
• The B vitamins help us use the
energy in food.
“B Deficiencies”
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•
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“Lack of energy”
“nausea”
“irritability/depression”
“loss of appetite/weight”
“loss of limb control”
….and about a hundred others!
• In children, full recovery may be
impossible.
• In the case of a thiamin deficiency
in childhood, permanent brain
damage can result.
“Individual B Vitamins”
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•
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•
•
•
Thiamin
Riboflavin
Niacin
Folate
B6 and B12
Biotin
Pantothenic acid
•
•
•
•
•
•
•
Tender
Romance
Never
Fails
With 6 or 12
Beautiful
Pearls.
“Thiamin”
• “found on nerve cell membranes”
• “So muscles depend on it greatly”
• Deficiency: beriberi spread in Asia
when rice was cleaned of outer
husk
• “alcohol impairs absorption”
• When alcohol abuse causes
thiamin deficiency, symptoms are
similar to the abuse:
• Apathy, irritability, mental
confusion, staggering walk
• Found in many nutritious foods
• Keep empty calories to a minimum,
you’ll be okay.
“Riboflavin”
• “in enriched breads, cereals, pasta,
dairy, veggies, meats”
• So again, deficiency is rare in the
U.S.
• “symptoms: cracks at corners of
mouth, hypersensitivity to light”
“Niacin”
• Deficiency: pellagra
• Killed hundreds of thousands in the
South and Midwest in the 1900s
• “pellagra: 4 D’s: diarrhea,
dermatitis, dementia, death”
• Still occurs in people living in urban
slums, particularly with alcohol
addiction
• When sufferers
are exposed to
light, skin
darkens and
flakes away, as
seen here.
Toxicity
• niacin flush: dilation of capillaries of
skin with intense, painful tingling
• Sometimes used as a drug in large
amounts to improve blood lipids
• Should only be done under doctor’s
supervision to prevent:
• Low blood pressure, liver injury,
vision loss
“Folate”
• “Helps to synthesize (make) DNA
when new cells form”
• Deficiency symptoms:
– anemia, abnormal digestive function,
impaired immunity
• May also elevate risk of cervical
cancer (in women with HPV), breast
cancer (women who drink), and
pancreatic cancer.
• Most likely to interact with drugs:
• Constant users of aspirin and
antacids may interfere with folate
• “Consumption of folate during
pregnancy can prevent neural tube
defects.”
Food Sources
• Folate comes from foliage:
• leafy greens, uncooked veggies
and fruits, eggs
• Folate anemia:
“Vitamin B12”
• “codependent with folate”
• “by itself, maintains sheaths that
protect nerve fibers”
• Deficiency: anemia
• “Comes from animal meat”
• So vegetarians must be cautious
• (Dairy, fortified cereals and soy)
“Vitamin B6”
• “Over 100 body roles”
• Convert one kind of amino acid to
another, less abundant one
• Important roles in blood hemoglobin
• Releasing stored glucose from
glycogen
• Development of brain and nervous
system
Loads of Symptoms
• Deficiency: weakness, insomnia,
convulsions, greasy dermatitis
• Possibly also heart disease
• Some take supplements for carpal
tunnel and insomnia, but research
shows this is ineffective.
Toxicity
• Unlikely from food consumption:
• One capsule can contain 2 g
• It would take almost 3,000
bananas, 1,600 liver portions, or
3,800 chicken breasts for that!
“Biotin and Pantothenic Acid”
• biotin: important for metabolism,
gene expression
• pantothenic acid: allows release of
energy from food
• Eating normal diets does not put
you at risk for deficiency.