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CARDIOLOGY
Vitamin D and
cardiovascular disease:
Where do
we stand?
In many large
observational
studies it was
shown that low
vitamin D levels
were associated
with an increase
in cardiovascular
disease.
» Doubling of the vitamin D
»
»
26
level is associated with
a reduction of 20% in
vascular mortality and a
reduction of 23% in non-
vascular mortality
Vitamin D deficiency is
common and is linked to an
increase in cardiovascular
disease worldwide
Sunlight every day for 10
minutes on the arms and
legs remains an effective
way to increase vitamin D
levels
|
May 2017
B
ackground facts
Vitamin D (D2 and D3) is a steroid
hormone and is produced in the skin
from 7-dehydrocholesterol by sunlight
(D2 and D3) or ingested with food from plant
origin (D2) or animal origin (D3) or from food
fortified with vitamin D.
The vitamin D then needs to be activated,
first in the liver to 25(OH) D and then in the
kidney to 1a25 (OH)D. Vitamin D acts through a
vitamin D receptor (VDR) which is a DNA-binding
transcription factor.
All tissues do have the vitamin D receptor.
Genome-wide studies have identified a genetic
influence on 25(OH)D levels.
Circulating levels of 25(OH)D is the best
indicator of whole-body vitamin D status and is
used to classify vitamin D status as sufficient or
insufficient or deficient.
Definition of vitamin D deficiency
Levels < 20ng/ml (< 50nmol/l) are used to
diagnose vitamin D deficiency. Levels between
21-29 as insufficiency, and normal as > 30ng/ml.
Worldwide the prevalence of vitamin D deficiency
is believed to be between 30-50% and most likely
higher in the elderly.
Risk factors known are ageing, physical
inactivity, smoking, obesity, housebound (or
indoor activity), dark skin (need more sunlight),
sunscreens and cover-up, and certain drugs
such as glucocorticoids. Not all risk factors are
probably known as yet.
Vitamin D and cardiovascular health
Atherosclerosis, a complex condi