SOMETHING NEW ABOUT
Khoa Noi tong hop
BS Nguyen Anh Tuan
• Vitamin D is a fat-soluble vitamin that was
isolated in 1930 and named calciferol.
• Vitamin D is actually a hormone precursor
which can be manufactured by the body.
• Vitamin D have a significant clinical role
because of their interrelationship with
calcium homeostasis and bone
Two form of vit D
• D2 (ergocalciferol) : is synthesized from
• D3 (cholecalciferol) : form in the skin when it
exposed to direct sunlight.
• D2,D3 not active in the body.It must be
metabolized by the liver and kidney into an
active form called Calcitriol and it promotes
absortion of calcium and phophorus from
Used of vit D
• Vitamin D is used for preventing and
treating rickets, weak bones
(osteoporosis), bone pain (osteomalacia),
preventing fractures in people at risk for
osteoporosis, prevention low calcium and
bone loss in people with kidney failure.
Used of vit D (cont.)
• Vit D is also used for condition of the heart
and blood vessels, including high blood
pressure and high cholesterol.
• For diabetes, obesity, muscle weakness,
multiple slerosis, rheumatoid arthritis,
chronic obstructive pulmonary disease,
asthma, brochitis, premenstrual
syndrome(PMS), and tooth and gum
Used of vit D (cont.)
• It is also used for boosting the immune
system, preventing autoimmune diseases,
and preventing cancer ( such as breast,
colon, skin ,pancreas and prostate cancer)
In heart and blood vessels
• Vit D deficiency was associated with lower
serum calcium, systolic and diastolic blood
pressure, lower HDL cholesterol.
• Low levels of vitamin D may play role in
the development of high blood pressure in
those with kidney disease.
• vitamin D may help prevent or treat high
In heart and blood vessels (cont.)
• people with low levels of vitamin D have a
greater risk of developing heart disease,
including heart attack, stroke, and heart
• Low levels of vitamin D may increase the
risk of calcium build up in the arteries
created atherosclerosis and can lead to a
heart attack or stroke.
Vit D and influenza
• Vit D insufficiency was associated with
increased risk of influenza and
supplementation of vit D reduce the
incidence of influenza.
• Vit D was found to protect against
influenza A, but not against the less
comon influenza B.
Vit D and influenza ( cont.)
• Vit D can stimulate the production of
cathelicidin antimicrobial peptides ( AMP)
and defensins, and inhibit cytokine
response to viral infection.
• Both mechanisms are extremely helpful in
the prevention of influenza and infectious
Mechanism of action
• AMP rapidly damage the lipoprotein
membranes of microbial targets, including
envelope viruses such as influenza.
• Vit D control both innate immunity and
• T cell ( killer cell ) must have vit D for
activation . Sufficient intake vit D , the T
cell will not be able to react.
• Getting enough vitamin D may lower risk
of certain cancers, especially of the colon,
breast, prostate, skin, and pancreas .
• Studies indicate that vitamin D may have
anti-cancer effects .
• People who have lower levels of vitamin D
are more likely to develop type 2 diabetes
than people who have higher levels of
• vitamin D deficiency increases the risk for
type 1 diabetes in children. (CDC)
Multiple Sclerosis (MS)
• Women who take at least 400 IU of
vitamin D daily lower their risk of
developing MS. And higher levels of
vitamin D in the blood seem to be
associated with a lower risk of developing
MS in white men and women.
• Studies have found that people who have
lower levels of vitamin D are more likely to
be obese compared to people with higher
levels of vitamin D.
• Studies (from the National Health and
Nutrition Examination Survey) suggest
that people with lower levels of vitamin D
have a higher risk of dying from any cause
compared to those with higher levels of
• The American Academy of Pediatrics
(AAP-2008) recommends 400 IU of
vitamin D daily for breastfed infants until
they are weaned and drinking at least 1
liter of whole milk or formula fortified with
vitamin D. The AAP also recommends that
children and teens who drink less than 1
liter of milk a day take 400 IU of vitamin D.
• The recommended adequate intake of
vitamin D to prevent deficiency in normal
infants and young children is 400 Int.
• Human milk typically contains less than 25
Int. Units of vitamin D per liter unless the
mother receives vitamin D
supplementation in high doses (eg, 2000
Int. Units per day).
Vit D supplementation (400 IU/day) is
recommended for each of the following groups
• All breast-fed infants; supplementation should
start in the first week of life. Supplements should
be continued until the infant is ingesting at least
400 IU of vit D daily through formula, milk, or
other food sources.
• All nonbreast-fed infants who are ingesting less
than 1000 mL of vit D fortified formula or milk
• Children and adolescents who do not ingest at
least 400 IU of vit D daily (eg, 1000 mL of
vitamin D fortified milk per day), do not get
regular sunlight exposure, and do not take a
multivitamin supplement that contains at least
400 IU of vit D.
• In a cross-section study ( involved 205
men and 432 women aged 18-85 ) in HCM
City, the prevalence of vit D insufficiency
in men was 20%, lower than woman 46%.
• Vit D insufficiency is common even in
tropical region, woman had a greater risk
of vit D insufficiency than man.
• For infants (birth to 12 months) the
tolerable Upper Limit, (maximum amount
that can be tolerated without harm) is set
at 1000 IU. 40,000 IU in infants has
produced toxicity within 1 month.The U.S.
Dietary Reference Intake Tolerable Upper
Intake Level (upper limit) of vitamin D for
children and adults is set at
50 micrograms/day (2,000 IU).
Vitamin D Excess
• Taking very high daily doses 50 or more
times the recommended daily allowance
(RDA)—over several months can cause
toxicity and a high calcium level in the
Vitamin D Excess
• Early symptoms are loss of appetite,
nausea, and vomiting, followed by
excessive thirst, weakness, nervousness,
and high blood pressure. Because the
calcium level is high, calcium may be
deposited throughout the body, particularly
in the kidneys, blood vessels, lungs, and
heart. The kidneys may be permanently
damaged and malfunction, resulting in
Vitamin D Excess
Diagnosed when blood tests detect a high
calcium level in a person who takes high doses
of vit D. The diagnosis is confirmed by
measuring the level of vit D in the blood (25-
Treatment consists of the following:
• Stopping vit D supplements.
• Following a low-calcium diet.
• Taking drugs (such as corticosteroids or
bisphosphonates) to suppress the release of
calcium from the bones.