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The Health Benefits of Vitamin D

I like to write about health and how to stay healthy by making smart decisions.

Aspirin has often been called the “wonder drug”; however, a closer look at vitamin D reveals that this well-known vitamin may be the actual “wonder drug”, due to the myriad health benefits it provides. Maintaining sufficient levels of vitamin D (also known as 25-hydroxy or calcidiol) in one’s blood serum appears to have many beneficial effects on a person’s health and well being. The beneficial health effects go far beyond the widely known beneficial role vitamin D plays in maintaining healthy bones and teeth. Some doctors and nutritionists are advocating for much higher daily recommended vitamin D intake amounts than the United States government recommends, in order to take full advantage of vitamin D’s positive impacts on human health.

Is Vitamin D The Real Wonder Drug


Vitamin D is a group of fat-soluble molecules called secosteroids. The two forms of vitamin D which are relevant to human beings are vitamin D2 (ergocalciferol) and vitamin D3 (cholecalciferol). Unlike other vitamins, which humans obtain exclusively from what they eat and drink, vitamin D is also obtained via photosynthesis when humans are exposed to sunlight. Vitamin D3 is produced in the skin of humans when the skin is exposed to ultraviolet B light from the sun or artificial sources. Vitamin D3 is also present in fish, egg yolks, mushrooms, and some other foods. It is also added to many staple foods, such as milk and flour to artificially fortify the foods with vitamin D. Vitamin D is also available as a supplement in both multivitamins and as an individual supplement pill, for those who wish to increase their vitamin D intake.

The recommended daily for vitamin D intake established by the United States government’s Food and Nutrition Board (FNB) sufficient to maintain bone health and normal calcium metabolism in healthy people is 600 international units (IU) for children and adults up to the age of seventy (70) years and 800 IU for seniors seventy (70) years an older. The reason why the recommended vitamin D intake level is greater for people over seventy (70) years of age is that the ability to synthesize vitamin D naturally in the skin declines with age and many older people do not spend as much time in the sun as their younger counterparts.

There are a growing number of doctors and nutritionists who believe the United States government’s recommended daily intake for vitamin D is far too low, as additional medical research indicates that higher levels of vitamin D intake and resulting higher levels of 25-hydroxy blood serum are necessary to take full advantage of vitamin D’s positive health effects. While not mainstream recommendations as of yet, some doctors and nutritionists are now recommending daily vitamin D intake of between 2,000 IU and 5,000 IU to maintain beneficial levels of 25-hydroxy blood serum and to replace the 3,000 IU and 5,000 IU of vitamin D that the body uses every day. These doctors and nutritionists are not worried about people reaching 25-hydroxy blood serum levels that are considered toxic because a much higher daily intake is necessary to reach toxicity. They argue that exposure to sunlight in the summer causes the human body to naturally generate 10,000 IU or more of vitamin D per hour with no ill effects.

To determine one’s current vitamin D 25-hydroxy blood serum level, one must have their blood tested either by either a testing lab or via a home testing kit. The doctors and nutritionists that recommend vitamin D intake of between 2,000 IU and 5,000 IU believe that the current medical standard of 30.0 nanograms per milliliter (ng/mL) for the 25-hydroxy blood serum level is insufficient for people to benefit properly from vitamin D. These doctors and nutritionists recommend 25-hydroxy blood serum levels be maintained between 30.0 and 80.00 ng/mL. The current medical standard toxicity threshold for the 25-hydroxy blood serum level is 200 to 250 ng/mL, while the upper limit (the amount up to which is considered safe and without risk of adverse effects) is 100 ng/mL.

Vitamin D and Your Health

Low 25-hydroxy blood serum levels result in impaired bone mineralization, and leads to bone softening diseases including rickets (impeded growth and deformity of the long bones) and osteomalacia (a bone-thinning disorder).

Mounting medical evidence suggests that maintaining an adequate 25-hydroxy blood serum level may have many beneficial medical effects on the human body. Sufficient 25-hydroxy blood serum levels have been found to have a positive impact on mood, reduce inflammation, reduce the risk of developing respiratory infections from the common cold and influenza viruses, and even prevent tooth decay, as it appears to boost the immune system’s ability to fight bacteria that cause tooth decay. Researchers have discovered that that maintaining an adequate 25-hydroxy blood serum level may help to prevent several cancers, cardiovascular disease, autoimmune disorders, psoriasis, diabetes, and psychosis.

Vitamin D Help Prevent Colds and Flu, Also Boosts Mood to Combat Wintertime Blues

Perhaps the most intriguing recent health benefit discovery regarding vitamin D and maintaining adequate 25-hydroxy blood serum levels is the finding that vitamin D reduces the risk of developing respiratory infections from the common cold and influenza viruses. It does so by increasing the formation of proteins called cathelicidin and defensins, which have antiviral effects that combat cold and flu viruses and by reducing inflammation in the body, which lowers body temperature and causes the lining of the lungs is be less disturbed. These Vitamin D effects on the body make it harder for viruses and bacteria to take hold in the lungs and limit the development of colds and flu in the human respiratory system.

It is interesting to note that the cold and influenza season coincides with the winter months of the year when humans have much less exposure to natural sunlight and produce little or no vitamin D from sunlight exposure. The reduction of vitamin D from sunlight and inadequate 25-hydroxy blood serum levels during the winter months could very well play an important role in the ability of colds and influenzas to spread and infect people whose vitamin D defenses are reduced during this time of the year, which is why it is important to maintain Vitamin D intake during the winter months.

The wintertime reduction of vitamin D from sunlight exposure and the resulting drop in 25-hydroxy blood serum levels might also contribute to major depression and wintertime Seasonal Affective Disorder (SAD), also known as the wintertime blues. Although research and studies into the connection between vitamin D and its effects on depression are limited, some studies have been performed that found vitamin D to be effective in improving the mood of persons with 25-hydroxy blood serum levels that are maintained above 40.0 ng/mL.

The health benefits provided by vitamin D and maintaining adequate 25-hydroxy blood serum levels throughout the year are becoming more evident with each passing year. Vitamin D has so many health benefits that it truly acts as a sort of “wonder drug” when taken at doses high enough to maintain beneficial 25-hydroxy blood serum levels. Like anything, too much vitamin D can be harmful and certain health conditions can be negatively affected by increasing vitamin D intake, so it is recommended to consult a doctor or other health care professional prior to changing one’s diet or vitamin supplement intake.

Vitamin D Supplements

Although I eat a diet that includes many sources of Vitamin D, I ensure I get enough of this important vitamin by also taking supplements on a daily basis. I have been taking Nature Made's Vitamin D3 1000 IU (25 mcg) tablets for many years and have been happy with their quality and effectiveness.

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This content is accurate and true to the best of the author’s knowledge and does not substitute for diagnosis, prognosis, treatment, prescription, and/or dietary advice from a licensed health professional. Drugs, supplements, and natural remedies may have dangerous side effects. If pregnant or nursing, consult with a qualified provider on an individual basis. Seek immediate help if you are experiencing a medical emergency.

© 2011 John Coviello


Neil Sperling from Port Dover Ontario Canada on December 11, 2014:

Good hub - and yes I know I "should" be taking Vit D. Especially in winter.... thanks for the reminder

Nadine May from Cape Town, Western Cape, South Africa on August 25, 2014:

I have just come back from having my coffee out in the sun after having read your hub. No I do not take any vitamins, but instead I take several different tissue salts. I should have during our winter. Often during our cold winter weather in Cape Town I rarely sit in the sun, so I had indeed attracted a head cold. I will from now on spent as much time in the sun as work allowed. I can't wait for the spring to be in full bloom. Thanks!

passionate77 on October 23, 2013:

i love vitamin d and always try to be regular taking my pill, as my mother suffered a lot due to vitamin d deficiency, since then i tried to take it at daily basis. great hub, enjoyed reading and learning, blessings for sharing dear!

Kate P from The North Woods, USA on October 26, 2011:

Great hub, voted up and awesome! I do take vitamin D supplements every day, and learned about it as a dental hygiene student (was glad to see you mentioned dental health).

All interested in the benefits of vitamin D may also be interested in Melatonin supplements!

Phil Plasma from Montreal, Quebec on July 19, 2011:

I take Vitamin D pills occasionally, but reading this makes me think I should be taking it daily and potentially at twice the dosage I am taking. Normally I take 1 1000iu per day, when I think of it, usually in the morning with breakfast. I could start taking it at night also. Thanks for the hub, it earns you a vote-up, useful and interesting.

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