There are more and more scientific studies backing up the fact that vitamin D plays an important role in the human immune system. There is also plenty of evidence showing that iv vitamin therapy long island is a major factor in prevention of common respiratory infections. One of the largest studies (Ginde et al. 2009) made of this topic revealed that people with the lowest blood vitamin D levels had substantially more cases of common colds or the flu.
Vitamin D is in fact a group of fat-soluble prohormones, the two most relevant forms for humans being vitamins D2 (ergocalciferol) and D3 (cholecalciferol). Vitamin D2 is produced in response to UV irradiation in some phytoplankton, invertebrates and fungi. Vitamin D3 on the other hand is produced in the skin of vertebrates in response to UVB light from the sun. Vitamin D3 can also be found in fish and few other foods. The recommendable supplemental form of vitamin D is vitamin D3. This is because vitamin D3 is the same substance that is produced in human skin after sun exposure. Supplemental D3 is usually derived from cod liver oil extract or lanolin.
Vitamin D level is defined by measuring blood serum’s concentration of 25-hydroxy-vitamin D. It tells us both the amount of vitamin D produced in the skin as well as the amount of vitamin D acquired through diet. The common conception has been that a concentration level above 15ng/ml (37,5 nmol/l) is adequate for those in good health. Desirable level for achieving good health has been a level above 30ng/ml (75nmol/l). However recent studies have revealed that the level which has conventionally been considered as normal is not the same as optimal. According to latest research it is very reasonable to believe that values presented below reflect more to optimal vitamin D levels:
deficient = <50ng/ml (<125nmol/l)
optimal = 50-70ng/ml (125-175nmol/l)
treating cancer or heart disease = 70-100ng/ml (175-250nmol/l)
excess = >100ng/ml (250nmol/l)
As a comparison to values presented above, the average late winter vitamin D level in the United States is roughly 15-18ng/ml (=37,5-45 nmol/l) Thus it comes as no surprise that according to some estimations 40-60% of global population is at risk for vitamin D deficiency.
There are only two ways to get enough vitamin D; vitamin D supplementation and sun (UVB) exposure. Exposure to the sun should be the number one method of choice. Studies have shown that large amounts of vitamin D are formed in the skin in response to full-body summer sun exposure. Important rules of thumb to remember when getting your vitamin D trough sun exposure are:
- sun exposure should be midday between 10am-2pm
- person with white skin will need around 15 minutes of full body sun exposure where those with darker skin will need even 3-6 times longer exposure
- sun exposure beyond the point where your skin starts turning red does not increase your skin’s vitamin D production any further, because when the equilibrium is reached in the skin the excess vitamin D is degraded by ultraviolet light
- there is no health benefits in getting sunburns
- not much vitamin D is formed in your skin if your shadow is longer than you are
- occasionally exposing your face and hands to the sun is not enough for vitamin D nutrition
- if your latitude is either above 30 degrees north or below 30 degrees south you will very likely need vitamin D supplementation roughly from September to mid-April
If you obtain your vitamin D trough sun exposure it is not necessary to test your vitamin D level because your body can’t overdose on vitamin D created trough sun exposure. However if you are taking vitamin D supplements, you should always make sure that you are taking the correct dose by testing your vitamin D level. Testing is best to be done after a few weeks from starting the supplementation.
The potency of vitamin D is measured in International Units (IU). One IU equals to 0.000025 milligrams (mg). Micrograms (mcg or µg) are also common way to present the potency, 40IU equaling to one microgram. The official recommendations for vitamin D intake usually vary somewhere between 400 to 1000 IU per day. These amounts are usually enough to maintain at least decent bone health and normal calcium metabolism in healthy people. In the light of latest research findings they can however be considered insufficient to raise and maintain the vitamin D level needed for proper health. For proper functioning a healthy human body consumes approximately 4000 IU of vitamin D per day. Thus the proper dose for a healthy adult should be somewhere between 4000 to 5000 IU per day. To set an example, Vitamin D Council recommends following supplemental vitamin D3 intake per day, in the absence of proper sun exposure.
- 1000 IU for healthy children under the age of 1 years
- 1000 IU per every 25lbs (11,3kg) of body weight for healthy children over the age of 1 years
- At least 5000 IU for healthy teenagers and adults
- At least 6000 IU for pregnant and lactating mothers
As a conclusion; by optimizing your vitamin D level you can help yourself to get rid of regular common colds and other respiratory infections. Proper vitamin D level also help in maintaining good health altogether. Sunlight should the number one source for vitamin D. If you are using vitamin D supplements it is wise to get your vitamin D level tested with nutritionally oriented physician