What
is Vitamin D?
Vitamin D works synergistically with vitamin A, preferring a 7:1
ratio. It plays a role in absorbing and regulating calcium and
phosphorus. It also helps build strong bones, teeth and skin. It is
vital to the health of the nervous system and kidneys.
It can be derived from the suns action on oils secreted and
reabsorbed by the skin. But the more tanned the skin, the less it
is absorbed. Also, the older the skin, the less active it is in
producing vitamin D. This vitamin helps the body synthesise protein
and incorporate magnesium into bone/teeth structures.
Benefits
of Vitamin D:
Bone
Health: The minerals calcium and phosphorus form a large
part of the substance hydroxyapatite, which makes up over half of
our bone composition. Two substances, however, primarily regulate
the body's use of calcium and phosphorus: parathyroid hormone
(PTH) and vitamin D. PTH triggers the release of calcium from our
bones into our bloodstream when levels drop too low.
Vitamin D, on the other hand, prevents PTH from drawing too much
upon our bones' supply of calcium by helping our intestines absorb
more calcium and by allowing our kidneys to hold onto more calcium.
By regulating our PHT function, vitamin D not only protects our
bone health, but also fights against too much calcium in our
bloodstream that can cause cardiovascular problems.
Immunity:
Vitamin D plays a crucial role in our immune system by triggering
macrophage cells that release antibacterial proteins. These
proteins are shown to possibly prevent infections, including
Mycobacterium tuberculosis (responsible for tuberculosis) and
Mycobacterium leprae (responsible for leprosy).
Blood
Pressure: Vitamin D may help to manage our blood pressure
by monitoring the system that increases our blood pressure when it
gets too low, called the renin-angiotension system. Our body needs
a healthy dose of vitamin D to inhibit this system from raising our
blood pressure too high.
Insulin:
Vitamin D regulates the levels of PTH from releasing too much
calcium into the bloodstream. An overdose of PTH in our bloodstream
can also cause fat cells to collect too much calcium, triggering
the cells to produce too much cortisol, a hormone that counteracts
the effect of insulin, making it difficult for the body to
metabolise sugars.
Furthermore, when too much calcium collects, our cells stop
producing GLUT*4, a protein that helps transfer sugar into the
bloodstream and to our cells. GLUT*4, however, functions only when
triggered by insulin. Without sufficient vitamin D, not only do our
bodies produce too little GLUT*4 to transport the necessary sugar
to our cells, but also lacks the effectiveness of insulin to
stimulate that process.
Muscles:
Studies have shown that a vitamin D deficiency not only leads to
decreased muscle strength (independent of muscle mass), but also
may inhibit proper nerve firing and triggering of muscle
contractions.
Mental
Health: Recommended intake of vitamin D may greatly reduce
the risks of age-related cognitive disorders, such as senile
dementia, Alzheimer's disease, and mood disorders such as
depression.