Vitamin D - the hidden benefits

Vitamin D - The hidden importance 

This is one of the most important vitamins in the body having a role in bone density, immune function, mood enhancement, and energy. Vitamin D3 , also known as cholecalciferol, is produced in the skin by exposure to sunlight especially UVB.

Only recently has the medical profession realised the importance of maintaining healthy levels of this fat soluble prohormone. It was mainly supplemented in the elderly and the very young for the promotion of bone formation and mineralization. The classic diseases of vitamin d deficiency are rickets, osteomalacia and osteoporosis.

What we have found in our clinical practice is that low levels are endemic in New Zealand with approx 80 %
of the people we test having inadequate levels. They are especially low in people with certain conditions such as chronic fatigue syndrome, depression, anxiety, cancer, auto immune disease , heart disease and recurrent infections.

We have a culture in New Zealand of being very careful to exposure of sunlight because   of our high rate of skin cancers including malignant melanoma, basal cell and sqaumous cell carcinoma. This high rate of skin cancer is thought due to our thin ozone layer over the South Pacific from Spring through to Autumn. This ozone hole in my opinion is more likely to be naturally occurring in view of the low population and hence low emission of fluorocarbons from our part of the planet. One theory is that active volcanoes spew out toxic gases that deplete the ozone layer such as Mt Erebus in Antarctica. The sun in New Zealand is incredibly harsh and you can burn quickly and badly if you are not careful!

As a result many New Zealanders and Australians cover themselves in sun block, wear hats, sun glasses and stay out of the sun as much as possible. This may help keep the skin cancer rate down but does lead to Vitamin D deficiency which can have the affect of increasing the risk of developing other cancers!

There is a degree of controversy with regards to the normal range of Vit D. In NZ we have a range of 50-150 nmol/l but people we test who have lived in the tropics frquently have levels over 200nmol/l. It is thought that toxicity occurs in levels over 350 nmol/l and hypocalcaemia (high calcium levels) can occur but usually when the levels are much higher (>1500nmol/l).

We try and maintain our patients between 100- 150 which is easily done with oral supplementation. The daily recommended supplementation for infants in USA is 200IU daily and Canada it is 400IU. The maximum production possible from a days sun exposure is 10,000 IU (250 ug). The body shuts down production of more vit d once this level is achieved. The maximum dose of vit D available over the conter in NZ is 1000IU which is very safe and unlikely to cause toxicity. This is a good adult daily supplementation.

Generally Vit D deficiency is only a problem in latitudes below 30 degrees. The further away you live from the equator the more careful you have to be. Once the sun drops down to below 45% from the horizon it is incapable of producing vit D in your skin which is the situation for most of late autumn and winter. It would be advisable to supplement at the end of summer in preparation for the upcoming winter.

People living in high latitudes such as Scotland, Canada, Alaska, Norway and Sweden are well aware of Seasonal Affective Disorder or SAD. This is a state of depression due to low sunshine hours in winter. This is linked to low levels  of melatonin , serotonin and Vitamin D. Supplementation of 5 HTP (precursor to serotonin ), melatonin (natural hormone made by the pineal gland ) and adequate Vitamin D could go a long way to preventing this . Antidepressant drugs should never be used for this physiological condition.
The more melanin pigment in your skin the longer the sun exposure has to be to achieve adequate levels of Vitamin D.This can mean up to 5 x the requred exposure for a black skinned person. The lowest levels (between 10 -20 nmol/l)are Indian and Middle Eastern patients who have quite dark skin and rarely expose their body to the sun for cultural reasons.

There are few foods that naturally contain high levels of Vitamin D and most is in the form of fortified products such as rice milk, soy milk, bread and cereals. The best natural sources are Fish liver oils (esp cod), 15mls provides 1360 IU
and oily fish species such as salmon , sardines, mackerel, tuna and eel. Mushrooms are a good vegetarian alternative but need to be exposed to 5 mins of sunlight after being harvested.

We have tested many blood levels , before and after treatment with high dose vitamin D and have found on average that 12 tabs of cholecalciferol (Vit D3)1.25mg or 50,000 IU each will raise the serum levels from 50-70 nmol/l.
We tend to dose with 1 tab daily for 6 days then have a break for 1 month and repeat the final six. The12 tabs is a standard pharmaceutical dose of 1 tab monthly for a year which is often given as a maintanence dose for those susceptible to Vit D deficiency. the main side affect of taking too much vit d is headaches which usually dissapate upon cessation  of treatment.

A person with sarcoidosis has to be carefull with vit d supplementation because of the risk of hypercalcaemia.

Nearly every patient we see with depression , psoriasis, autoimmune diseases, chronic fatigue syndrome , multiple sclerosis and cancer have very low Vitamin D levels. We supplement these patients and there is always an improvement in their well being and energy . In a  randomised intervention study reported in June 2007 involving 1200 woman taking 1100IU vit d daily there was a 60% reduction in cancer incidence over 4 years. This is huge and should be known by every one.
Likewise Ethiopian children with ricketts were 13 x more likely to get pneumonia than those without ricketts and  presumed normal levels of Vit D.

There is plenty of evidence to back up my belief that Vit D is one of the most important nutrients for normal function of the human body. A lot of our Western diseases are associated with this deficiency and you are being very smart to go and get your level checked asap or start supplementation if you suspect you are deficient.

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