Vitamin Information Center

By Skowron, Jared M

Myth 1: Vitamin D is a vitamin. The Truth: Vitamin D is a hormone. It’s derived from cholesterol. It activates cellular processes and does not do so as a co-factor. Vitamin D receptors nave direct effects on the following cells: adipose, adrenal, bone, brain, breast, cancer, cartilage, colon, endothelium, epididymis, ganglion, hair follicle, intestine, kidney, liver, lung, muscle, osteoblasts, ovary, pancreatic B, parathyroid, parotid, pituitary, placenta, prostate, skin, stomach, testis, thymus, thyroid and uterus.

Myth 2: Normal activity provides us enough vitamin D from sun exposure.

The truth: Most people do not get enough sunshine to maintain adequate vitamin D levels. Our ancestors spent most of the day in the sun, farming, fishing and hunting. Our bodies physiologically developed to need that much vitamin D. Today’s indoor society of office workers, television watchers and hermits gets much less sun exposure and vitamin D production. Add on clothing and sunscreen, which also inhibit vitamin D production, and you understand the problem.

Myth 3: Supplemented vitamin D in foods is adequate.

The truth: Vitamin D^sub 2^ is one-third as effective in the body as naturally occurring vitamin D^sub 3^. Most foods have D^sub 2^ added. A study that analyzed vitamin D^sub 2^ levels in milk off supermarket shelves showed almost 50 percent had less than the label claim of 400 IU of D^sub 2^. A support scientist from the USDA believes no food-label claims are accurate and these labels cannot be trusted.

Myth 4:1,25(OH)D3 is the best analysis for vitamin D levels.

The truth: Vitamin D is mostly stored in adipose and should not be routinely measured. It then converts to 25(OH) D3, which has a long half-life and is the best analysis of vitamin D levels. It then converts to bi-hydroxy forms such as 1,25(OH)D3, 24,25(OH) D3 and other forms, which have the actual action of the cell receptors. However, this form has a short half-life and is not a good measurement.

Myth 5: The reference range for vitamin D levels is accurate.

The truth: The reference range for 25(OH)D3 is horribly inaccurate and is maintaining our vitamin D deficiency in this country. The current reference range of 20-100 is too low. Levels <25 are disease level. Levels between 25 and 75 are suboptimal. Levels between 75 and 200 are optimal.

Myth 6: Vitamin D supplementation is nontoxic.

The truth: The major consequence of vitamin D toxicity is hypercalcemia, which should be monitored periodically while under therapy. Changes in cardiac rhythms or lithiasis are common concerns. Urine calcium monitoring is not accurate. Serum calcium .should be monitored monthly to check vitamin D toxicity, which normally occurs at 40,000 IU/day. Right now, 10,000 IU/day is being proposed as the safe upper limit.

Myth 7: The RDA for vitamin D is accurate.

The truth: People taking only the RDA of vitamin D will lower their 25(OH) D3 levels. The RDA is too low. When treating with vitamin D supplementation, three months of daily dosing is sufficient to max out 25(OH)D3 levels. Five thousand IU/day for three months should elevate 25(OH) D3 by 80 nmol/L, and 10,000 IU/ day for three months should elevate 25(OH) D3 by 120 nmol/L. People on 1,000 IU/day will elevate their levels by only 10 nmol/L.

Myth 8: Different forms of vitamin D are all the same.

The truth: Vitamin D^sub 3^ is the preferred form. Avoid D^sub 2^ at all costs. D^sub 3^ is derived either from plant sources or from lanolin. Lanolin-derived D^sub 3^ is more active and absorbable. I take the 10,000 IU capsules of D^su 3^.

Myth 9: Vitamin D only treats osteoporosis and rickets.

The truth: The therapeutic benefits of vitamin D are still being discovered. Benefits relative to cancer, cardiac, immune-boosting, diabetes and neurological (such as multiple sclerosis) therapies, as well as low bone density, are just the tip of the iceberg. I test all of my patients for vitamin D deficiency and supplement regularly up to the 75-200 reference range of 25(OH)D3.

Myth 10: Vitamin D should be avoided in pregnancy and breastfeeding.

The truth: Pregnant women should receive 4,000 IU of daily vitamin D supplementation. Breast-feeding women should receive 6,000 IU of daily vitamin D supplementation. Vitamin D, not 25(OH)D3, crosses into the breast milk, and daily doses are preferred over weekly doses. Avoid supplementing the infant and instead supplement the breast-feeding mother directly. If the infant is bottle-fed, supplement with 400-800 IU/day.

By Jared M. Skowron, ND

Bio

Dr. Jared M. Skowron is in private practice in Hamden, Conn., where he specializes in pediatrics and treating autistic spectrum disorders in children. He is the senior naturopathic physician with Metabolic Maintenance and an adjunct professor at the University of Bridgeport, teaching pediatrics, CPD and EENT.

Vitamin D helps build strong bones by promoting the absorption of calcium.

There’s something simple you can do to help protect yourself against ailments ranging from cancer to depression. Chances are, you’re not taking the cure.

It’s vitamin D and some experts believe as many as 50 percent of healthy adults and children are deficient in this essential nutrient.

Doctors across the country have begun prescribing high doses to patients who are surprised to learn they’re deficient. Yet doctors and researchers say the vitamin D problem could be solved if we just got out in the sun.

Question: What’s so important about vitamin D?

Answer: For years, doctors have known vitamin D helps build strong bones by promoting the absorption of calcium. (The vitamin was added to milk more than 50 years ago to successfully combat the common childhood bone disease of rickets.) But recent research indicates D is important to almost all body tissues. Low levels of vitamin D have been linked to increased risk of breast and prostate cancer, colon polyps, multiple sclerosis, Type 1 diabetes, muscle weakness , even depression and schizophrenia.

Q: Why are so many people deficient?

A: Two reasons. People aren’t spending enough time in the sun and it’s hard to get enough vitamin D from food. The best way to get it is by being in the sun, since skin produces plenty of D when exposed to the sun’s rays. But office workers and kids playing video games often don’t spend enough time outdoors to make the D they need. And when they are outside, they’re probably wearing sunscreen. Sunscreen with an SPF of 8 blocks more than 95 percent of the sun’s capacity to make vitamin D in your skin.

Fortified milk, yogurt and orange juice contain about 100 International Units of vitamin D per one-cup serving. Canned salmon contains 300 to 600 IU. Doctors used to think 400 IU daily was enough for most adults. But new research indicates that is too low. Dr. Michael McClung, director of the Oregon Osteoporosis Center, recommends adults get 1,000 to 2,000 IU of vitamin D each day, unless their blood calcium is too high or they’ve had kidney stones.

Q: Who is most at risk of vitamin D deficiency?

A: “The farther you live from the equator and the less opportunity you have for regular sun exposure, the more likely you are to be deficient,” says Charlotte internist Dr. Charles Rich.

Older adults are more at risk. Obesity and liver or kidney disease also increase your risk. Blacks and people with darker skin are more at risk, because their skin is less able to synthesize Vitamin D from the sun.

Q: What are the symptoms of deficiency?

A: Often there are none. Debra Wilform, 49, of Charlotte, N.C., learned she was low in vitamin D after a blood test during a routine physical last year. She had no symptoms. Her doctor prescribed 50,000 IU of D2 once a week for six weeks, then once a month for six months. She’ll be re-tested in March.

Q: How much Vitamin D do I need and what are the best sources?

A: There’s still disagreement on how much D is enough. The New England Journal of Medicine says adults and children need 800 to 1,000 IU of vitamin D daily if they’re not getting enough sun exposure. McClung says it’s safe for adults to take 1,000 to 2,000 IU daily. (You’d need to drink 10 glasses of milk to get 1,000 IU.) Cautious sun exposure is the easiest way to get enough vitamin D. The National Institutes of Health says 10 to 15 minutes in the sun at least twice a week with your arms, hands, face or back exposed without sunscreen is usually enough.

Children and healthy adults make about 25,000 IU of D by spending 15 minutes in the sun with their face and arms exposed before applying sunscreen, says McClung. Because D is stored in fat and muscle, you can build up reserves to draw on later. But the farther north you live, the harder it is to get enough D from sun exposure alone. From November through February, people living north of Atlanta make little or no vitamin D by being outdoors.

Q: Should I be tested?

A: Ask your doctor. The test costs about $100 and is often covered by insurance. For many people, McClung just recommends over-the-counter supplements.

By spending 10 to 15 minutes in the sun at least twice a week with your arms, hands, face or back exposed you can increase your vitamin D intake.