Vitamin D Benefits: Prevention of Cancer, Colds, Influenza, and more

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Vitamin D supplementation is not only effective for cancer prevention and treatment, but for a long list of other conditions including influenza

Vitamin D is not really a vitamin but a steroid hormone precursor that plays a major role in many diseases. It is created under the skin by ultraviolet light and is found in few foods commonly consumed by most Canadians.

Vitamin D deficiency or insufficiency (sub-optimal levels) has been found to play a role in causing 17 types of cancer (especially breast, prostate and colon). Deficiency of D has also been linked to heart disease, stroke, hypertension, autoimmune diseases like multiple sclerosis, diabetes, depression (especially seasonal affective disorder), chronic pain, fibromyalgia, osteoarthritis, osteoporosis, muscle weakness, muscle wasting, birth defects, and periodontal disease.

In my practice, at least half the patients I see for chronic health problems have insufficient blood levels of vitamin D despite consuming vitamin D fortified dairy products or taking a multiple vitamin supplement. Sun-phobia, a condition imposed on the population by sun-paranoid dermatologists, along with sunscreens and spending too much time indoors have all contributed to the vitamin D deficiency problem. In fact, one of the worst offenders in creating vitamin D deficiency is the use of commercial sun blocks. And studies now indicate that while these may prevent sunburns, they do virtually nothing to prevent skin cancer.

Research indicates that to get 4,000 IU of vitamin D, if you totally avoid the sun, you must drink 40 glasses of milk a day or take 10 typical multivitamin pills daily. As mentioned earlier, a more optimal daily dose of vitamin D is 10,000 IU.

The purported toxicity of vitamin D is overstated. According to well-documented research, a person standing in the summer sun for an hour at noontime in a southern latitude in swim trunks, would naturally produce about 10,000 IU of vitamin D through skin exposure. But sun poisoning from vitamin D overdose has never been reported anywhere.

For those who cannot tolerate the sun and prefer to take supplements, Dr. Reinhold Vieth PhD, researcher at the University of Toronto, notes that vitamin D toxicity begins at 40,000 IU daily only after many weeks of use. Taking 10,000 IU daily for months at a time, provided there is no sun exposure, is perfectly safe. Blood levels can be tested periodically to verify this.

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Take Vitamin D3 with K2 and Magnesium

No amount of vitamin D supplementation will be effective if one is deficient in magnesium. So, to make vitamin D beneficial for the cardiovascular system and bone health most adults need to also supplement magnesium bisglycinate, at least 400 mg daily. Do not use magnesium citrate because that has minimal, if any, absorption into the system and is primarily used to move the bowels for good bowel movements.

Another very important nutrient to take with vitamin D supplementation is vitamin K. The reason for this is because studies have shown that calcium deposition into the arteries and organs like the kidneys can be prevented when one uses high supplemental doses of vitamin D. Vitamin K is also important in preventing and treating osteoporosis.

You may have noticed that health food stores and pharmacies are selling vitamin D with vitamin K2. For each 1,000 IU of supplemental vitamin D one needs to take 120 mcg of vitamin K2. Vitamin K is anti-inflammatory and, along with omega-3 makes vitamin D supplementation more effective.

Besides Cancer Prevention, Why Take Vitamin D?

Vitamin D supplementation is not only effective for cancer prevention (60% of all cancers can be prevented) and treatment, but for a long list of other conditions. Below are a rapidly growing number of health problems that are proven to be either prevented or treated effectively by boosting the blood levels of vitamin D:

RICKETS – Even conventional medicos know this childhood bone disease is caused by vitamin D deficiency, and was the major reason why milk became fortified with tiny doses of the supplement.

OSTEOPOROSIS – Even though this is common knowledge, many people who suffer from osteoporosis are low in their D levels and simply need to take more.

HEART DISEASE – Hardening of the arteries is caused by calcium deposition. Vitamin D is an anti-calcifying agent when at optimal levels in the bloodstream; both extremely high and low intake levels of vitamin D induce calcification of arteries but calcification from overdose of vitamin D requires many hundreds of thousands of international units and is rare. Vitamin D deficiency is common and calcified arteries are a direct result of deficiency. Also, as is noted below, heart disease is often triggered and perpetuated by inflammation, and vitamin D is anti-inflammatory.

DIABETES – Evidence is mounting that vitamin D can improve insulin resistance and favorably affect Type 2 diabetes.

HYPERTENSION – Emerging evidence has compared the blood pressure-lowering effects of vitamin D to ACE inhibitors, a class of blood pressure-lowering drugs commonly prescribed by conventional doctors. Don’t go off your blood pressure pills yet but consider high dose supplements of vitamin D and get your blood levels checked along with your blood pressure.

COMMON COLD AND INFLUENZA – Ditch that mercury and formaldehyde laden flu shot; vitamin D has strong antibiotic properties and some studies indicate that optimal blood levels will prevent influenza far better than those toxic ‘flu shots. Dr. John Cannell, the director of the Vitamin D Council, suggests high-dose vitamin D (50,000 IU) be consumed for three days at the first sign of a cold or the ‘flu. If you have an infection, you need more vitamin D. That’s a given.

AUTISM – Research has shown that low maternal vitamin D levels can adversely affect the developing brain and lead to autism, and that vitamin D supplements can improve some of the signs of autistic behaviour. Since most of the medical and conventional treatments for autism are so dismal, supplementing with vitamin D may be well worth a try.

INFLAMMATION – vitamin D is anti-inflammatory; if you have inflammation (arthritis, iritis, thyroiditis, pancreatitis, anything ending in “itis”), you need more vitamin D.

AUTOIMMUNE DISEASE – multiple sclerosis, psoriasis, scleroderma, rheumatoid arthritis, fibromyalgia, chronic fatigue syndrome and numerous other diseases where the immune system attacks various organs, involves inflammation that can be arrested by a high dose vitamin D.

MELANOMA– this most deadly form of skin cancer is now thought to be caused by a sunlight/vitamin D deficiency; safe sun exposure actually helps prevent melanoma, a counter intuitive finding confusing the heck out of dermatologists.

OBESITY – vitamin D levels are significantly lower in overweight individuals; taking a vitamin D supplement certainly beats dieting but check your blood levels first.

The Bottom Line

The only way to ensure vitamin D adequacy is to expose yourself to the sun regularly.  In Canada and other northern latitude countries, this is next to impossible at any time other than the summer. As discussed earlier, drinking milk is not the answer. Although frowned upon by frumpy dermatologists, I recommend people use a sun bed (avoiding sunburn) during the winter months. Either that or make frequent trips to Florida, southern California or the Caribbean.

For people who want nothing to do with sun beds or trips to the deep south, there are oral supplements that will do the trick. One choice would be cod liver oil or halibut liver oil liquid or capsules. The only problem here might be the high vitamin A (each capsule may contain as much as 5000 IU of vitamin A) that comes along with the vitamin D (usually 200 – 400 IU per capsule). If you want to take 2000 IU daily of vitamin D, then fish liver oil capsules might be suitable. If you want to push the dose up to 10,000 IU of vitamin D daily, you might be getting too much vitamin A.

If you suffer from any chronic health problem, ask your doctor to check your blood level of 25-hydroxy vitamin D, the most accurate indicator of vitamin D status.  The optimal blood levels should be between 100 and 250 ng/ml. Levels below 50 are considered insufficient and levels below 25 are definitely in the deficiency category. With continued research, I predict these numbers will all change, so stay tuned.

Dr. Rona is author of “Vitamin D: The Sunshine Vitamin”


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