By Todd Neale, Staff Writer, MedPage Today April 28, 2010 Reviewed by Robert Jasmer, MD; Associate Clinical Professor of Medicine, University of California, San Francisco and Dorothy Caputo, MA, RN, BC-ADM, CDE, Nurse Planner
PRAGUE — Among patients who have suffered a traumatic brain injury, vitamin D deficiency is associated with an increased likelihood of having chronic fatigue, Dutch researchers found.
Of 90 such patients, 80% who were fatigued had the vitamin deficiency, compared with 40% of those who were not fatigued (P<0.05), Jessica Schnieders, MD, of Rijnstate Hospital in Arnhem, the Netherlands, reported at the European Congress of Endocrinology in Prague.
Having a sleep disorder strengthened the association between vitamin D deficiency — defined as a level less than 50 nmol/L — and fatigue, Schnieders said in an interview.
“I think it’s important to get knowledge to the patients, the rehabilitation doctors, and the family doctors that they should look at vitamin D and sleep in these patients,” she said.
Schnieders said all of the patients who had a vitamin D deficiency were treated, and many said they felt better.
Although the study could not establish a causal relationship between low vitamin D levels and fatigue, treating the vitamin deficiency can benefit other areas, including bone health, she said.
Previous studies have shown that some patients with a traumatic brain injury have hormone deficiencies related to damage to the pituitary gland. Schnieders and her colleagues wanted to find out whether this, as well as other factors like vitamin D deficiency, might explain the fatigue commonly seen after traumatic brain injury.
The researchers randomly selected 100 former patients of their rehabilitation center to participate in the study, and 90 agreed (26 females and 64 males). It had been about 10 years since the traumatic brain injuries.
All filled out a fatigue questionnaire and provided information on emotional well-being, quality of life, attention, coping style, daily activity, and physical performance as assessed on a cycling test. The researchers also measured vitamin D levels.
Slightly more than half (51%) of the patients reported being severely fatigued. As expected, these patients had more anxiety and a lower quality of life.
Deficiency in at least one of the pituitary hormones was identified in 29%, growth hormone deficiency was found in 24%, and gonadal hormone deficiency was observed in 10%. None of these deficiencies was significantly related to fatigue.
In a multivariate analysis including hormone deficiencies, vitamin D deficiency, sleep problems, attention, body mass index, and gender, vitamin D deficiency was the only factor independently associated with fatigue (P<0.05).
It is unclear why sleep problems strengthened the negative effect of vitamin D deficiency on fatigue, but Schnieders said there is some evidence linking melatonin, which is involved in regulating circadian rhythms, and vitamin D.
The observational study could not prove that vitamin D deficiency was causing the fatigue.
Schnieders said another possible explanation for the findings could be that fatigued patients are more likely to remain inside and not get enough exposure to sunlight.
“But I think it has something to do with the immunological system because both sleep and vitamin D are involved in the immunological system,” she said.
Schnieders reported no conflicts of interest.
Recent evidence has shown that pregnant mothers who were given 4,000 IU (ten times the usual dose) of vitamin D daily had only half the risk of giving birth to premature babies as those who were not supplemented.  That amount can also be produced by about 20 minutes of full- body exposure to non-burning sunlight at midday.
The importance of this information is shown in the fact that annually, half of all premature babies die in the first month after birth, according to the March of Dimes. In North America, about 500,000 premature births occur annually. If vitamin D supplementation could prevent half of these deaths, that would save the lives of 250,000 babies per year. Worldwide, the lives saved might be as many as 7 million, since approximately 13 million babies are born prematurely each year. We also know that the average cost for each premature baby in the first year of life is about $49,000. http://www.marchofdimes.com/aboutus/22684_55250.asp
Premature babies, of course, are also low-birth-weight babies in most cases, which present an additional problem. Here is one more reason for mothers to get back in the sunlight: the potential for low birth weight in their babies.
Low birth weight is associated with poor mood, anxiety, depression, high blood pressure and other problems during childhood and afterward. Recent research shows that low birth weight is related to exposure by pregnant women to winter temperatures during a critical developmental time for the fetus.  This could indicate vitamin D deficiency of the pregnant mother during “vitamin D winter,” the time of year in northern latitudes when the sun is too low in the sky to produce vitamin D. The answer, of course, is to use a tanning bed or take vitamin D3 supplements (3,000-5,000 IU) during the winter. Remember never to burn!
Those who make a living frightening people out of the sunlight are responsible for much of the vitamin D deficiency in the population of North America. Don’t expect them to change. Non-burning sunlight is a wonderful gift for health, and we must stop the insanity that is causing vitamin D deficiency. The child needs every possible advantage prior to birth, and one of the advantages is a mom with high vitamin D levels. The only source of vitamin D for the fetus is the mother’s body, and the only natural way to obtain vitamin D is exposure to sunlight.
 Hollis, B. and Wagner C. Report from an international conference on vitamin D in Bruges, Belgium.  March of Dimes statement Oct 4, 2009, based on World Health Organization (WHO) statistics.   Elter K, et al. Exposure to low outdoor temperature in the midtrimester is associated with low birth weight. Aust N Z J Obstet Gynecol 2004;44:553-7.  Murray, L. et al. Links of Season and outdoor ambient temperature: effects on birth weight. Obstet Gynecol. 2000 Nov;96(5 Pt 1):689-95. – See more at: http://www.sunlightinstitute.org/do-250000-north-american-babies-die-each-year-due-vitamin-d-deficiency#sthash.LO4THgwB.dpuf
It appears that the first case of drug-resistant TB has arrived in the US from Peru. It is nearly 100% resistant to antibiotics, and does not bode well for the country, since it could cause an immense killer epidemic. There seems to be no answer to the “superbug” that causes it. Or is there an answer? Could sunlight and its skin-produced hormone, vitamin D, provide answers to this latest health threat?
Sunlight has a long history of treatment for tuberculosis. Much of the following discussion of TB comes from Dr. Fielder’s history of heliotherapy.
As early as 1857 Madame Duhamel of France exposed children with TB to sunshine because it hastened their recovery. Many doctors of that same era used heliotherapy (sunlight treatments) with great success, and as Dr. Fielder states, “As a general rule, the experience of all the Hygienists in their use of sunbathing was so successful that all question of doubt as to its place in the Hygienic System was ensured.”
Madame Duhamel was correct about sunbathing healing tuberculosis (TB). Later on, a disillusioned physician, Dr. Rollier, gave up a promising surgical practice and moved to the mountains of the Swiss countryside to practice medicine there. However, he discovered that the people needed little help, as they were seldom sick. People were always telling him, “Where the sun is, the doctor ain’t [sic].” In fact, Dr. Rollier’s fiancée had TB and would have died without intervention. He brought her to the Alpine area, exposed her regularly to sunshine, and she completely recovered.
Dr. Rollier opened a sanatorium in 1903 that was really just an extremely large solarium (sunbathing facility) with patient living quarters. There were 2,167 patients under Dr. Rollier’s care for TB following World War One. Of these, 1,746 completely recovered their health. Only those in the most advanced stages of the disease failed to recover.
In 1895, Dr. Niels Finsen made use of the first artificial UV light in treating patients with a particularly virulent form of TB known as lupus vulgaris (a skin disease). Though the disease was considered incurable, 41 of every 100 patients under his care recovered. Finsen’s work earned the Nobel Prize in medicine in 1903.
These researchers and physicians were not alone in their observations of the therapeutic power of sunlight. In 1877 two scientists, Arthur Downes and Thomas Blunt, discovered that sunlight was bactericidal. In 1890, the German microbiologist Robert Koch (who had isolated and described the tuberculosis bacterium in 1882), showed that sunlight killed TB bacteria.
Recently, the interest in Vitamin D to thwart TB is being revisited.   and it has been shown that Black immigrants to Australia have much lower vitamin D levels than the general population and a much higher risk of TB. Moreover, the effectiveness of vitamin D was demonstrated against the TB bacteria in an experiment in which a single dose of vitamin D (100,000 IU) significantly increased immunity to the TB bacterium. The effectiveness of vitamin D against TB is determined by the production of cathelicidin, an antibacterial peptide, which we could call the “body’s natural antibiotic.”
Further corroborating vitamin D’s essential role is that people who lack vitamin D receptors (VDR) are three times more likely to contract TB as those with normal VDR. Vitamin D also inhibits the body’s inflammatory response to TB infection in the lungs.  Considering the efficacy of sunlight therapy and vitamin D in inhibiting or even curing tuberculosis, doesn’t it seem that it’s time to return to the sun? Remember that you should never burn yourself in the sunlight.
 http://www.sphere.com/nation/article/first-case-of-highly-drug-resistant…  Fielder, J. Heliotherapy: the principles & practice of sunbathing. Soil and Health Library (online) http://www.soilandhealth.org/index.html.  Hobday, R. The Healing sun. Findhorn Press 1999:132  Martineau, A. Effect of vitamin D supplementation on anti-mycobacterial immunity: a double-blind randomized placebo-controlled trial in London tuberculosis contacts. Int J Tuberculosis Lung Dis 2005;9:S173.  Martineau, A. et al. Vitamin D status of tuberculosis patients and healthy blood donors in Samara City, Russia. Int J Tuberculosis Lung Dis 2005;9:S225.  Nnoaham, K. et al. Low serum vitamin D levels and tuberculosis: a systematic review and meta-analysis. Int J Epidemiol 2008;37:113-19. Gibney, K. et al. vitamin D deficiency is associated with tuberculosis and latent tuberculosis infection in immigrants from sub-Saharan Africa. Clin Infect Dis 2008’46:443-46. Martineau, A et al. A single dose of vitamin D enhances immunity of mycobacteria. A J Respir Crit Care Med 2007;176:208-13. Liu, P. et al. vitamin D mediated human antimicrobial activity against mycobacterium tuberculosis is dependent on the induction of cathelicidin. J Immunol 2007;179:2060-63. Liu, W. et al. A case-control study on the vitamin D receptor gene polymorphisms and susceptibility to pulmonary tuberculosis. Zhonghua Liu Xing Bing Xue Za Zhi 2003;24:389-92.  Selvaraj, P et al. Regulatory role of promoter and 3’ UTR variants of vitamin D receptor gene on cytokine response in pulmonary tuberculosis. J Clin Immunol 2008; January 30. Epub ahead of print. Vidyarani, M. et al. 1, 25 Hydroxyvitamin D3 modulated cytokine response in pulmonary tuberculosis. Cytokine 2007;40:128-34. – See more at: http://www.sunlightinstitute.org/will-vitamin-d-stop-new-killer-strain-drug-resistant-tuberculosis-or-sunlight-cure#sthash.PTDnd37d.dpuf
40% of Children Have Vitamin D Deficiency How to Make Sure Your Kid Isn’t One of Them
By Dan Shapley April 6, 2010
At least 40% of infants and toddlers, and 42% of teens, aren’t getting enough vitamin D, the “sunshine vitamin,” according to new research.
Vitamin D is produced when the body reacts to sunlight, and helps the body absorb calcium. Without it, people are prone to bone disease, autoimmune diseases like diabetes, multiple sclerosis and certain cancers, as the Washington Post put it — as well as increased risk for heart attacks (learn more here).
The new Boston Children’s Hospital research, on infants and toddlers, suggests that nursing mothers should be giving their children Vitamin D supplements, since human breast milk lacks the fortification given to store-bought milk.
Teens may also need supplements, researchers told the Post.
Another solution we humbly suggest? Go outside. While it is important to be careful to avoid overexposure to the sun, there’s no reason people can’t get more Vitamin D the natural way.
In our hyperconnected, hyperfearful times, we’re more apt to stay indoors plugged into a computer, video game, television or PDA than to take a walk outside, play sports, fish or otherwise get some sun. Parents are increasingly concerned about the threat of pedophiles and the like, so children are less apt to just take off for the great outdoors unsupervised.
There were already good reasons to make sure – via whatever extra effort is necessary – that children aren’t suffering from so-called nature deficit disorder. There’s the food for the soul argument, the inspiration for creativity argument, the exercise for health argument, and now there’s another: good nutrition.
It’s a poignant commentary about a society when its children lack the sunshine vitamin.
Children who took vitamin D supplements during the cold and flu season escaped seasonal flu and asthma attacks, according to a study published in the American Journal of Clinical Nutrition and reported by Reuters.
For the three-month study, done during cold and flu season, researchers from the Jikei University School of Medicine in Tokyo randomly assigned 167 children, ages 6 to 15, to take 1,200 international units (IU) of vitamin D-3 or a placebo each day.
Vitamin D-3 is more readily absorbed and more potent than vitamin D-2 (usually found in multivitamins).
Scientists noted that only 18 children taking vitamin D caught influenza A compared with 31 kids taking the placebo. Overall, the vitamin D group was 58 percent less likely to catch influenza A.
In addition, vitamin D also seemed to suppress asthma attacks in children with a history of asthma. Two children taking the supplement had asthma attacks compared with 12 children taking the placebo.
Based on the study, researchers concluded that vitamin D-3 supplements may reduce influenza A. They also suggested parents check with their pediatricians about giving their children 1,200 IU of vitamin D per day starting in September to prevent asthma and flu during the flu season.
By BJS —
Forty-three percent of patients scheduled to undergo orthopaedic surgery have insufficient levels of vitamin D and two out of five of those patients had levels low enough to place them at risk for metabolic bone disease, according to a study published this month in the October 6th issue of the Journal of Bone and Joint Surgery (JBJS).
According to the National Institutes of Health (NIH) , vitamin D helps the body absorb calcium and is essential for bone growth and bone remodeling. Without sufficient vitamin D, bones can become thin, brittle or misshapen. People can obtain vitamin D in three ways:
•by eating certain types of food (including fish, dairy products, eggs and
•receiving sun exposure; and
“Given the importance of vitamin D in musculoskeletal health and its role in bone healing following orthopaedic procedures, low levels may negatively impact patient outcomes,” said orthopaedic surgeon Joseph M. Lane, MD, study co-author and chief of the metabolic bone disease service at the Hospital for Special Surgery in New York.
All 723 patients in the study had been cleared by a specialist in internal medicine for elective surgery in one of the following orthopaedic service areas: Trauma, Foot and Ankle, Sports Medicine (only ACL and/or meniscal repair), Arthroplasty (only primary total hip and knee replacement), Hand (only distal radial or ulnar fracture) and Metabolic Bone Disease (only vertebral compression fracture).
The researchers found that, of the 723 patients studied,
•411 (57 percent) had normal Vitamin D levels,
•202 (28 percent) had insufficient levels; and
•110 (15 percent) were vitamin D deficient.
“We found that nearly half of the patients who were considered ‘healthy’ enough for surgery had significantly low levels of vitamin D, placing them at risk for poor bone healing, osteomalacia (bone and muscle weakness) or even secondary hyperparathyroidism (increased secretion of the parathyroid hormone) in the most severe cases,” said Dr. Lane, who is also a professor of orthopedic surgery at Weill Cornell Medical College in New York. “This was very disconcerting since vitamin D levels can be determined with a simple blood test and low levels can be easily treated with supplements in just a few weeks.”
When results were broken down by orthopaedic service area, researchers uncovered a surprising finding: Despite having the youngest mean population (age 45 ± 14.9 years), the Sports Medicine group of patients had the second-highest rate of vitamin D insufficiency (52 percent) — exceeded only by patients in the Trauma group (66.1 percent). The remaining groups had insufficiency levels of 40 percent (Hand), 38 percent (Arthroplasty), 34 percent (Foot and Ankle) and 18.6 percent (Metabolic Bone Disease).
The researchers noted that their results are consistent with those of similar studies investigating the prevalence of vitamin D deficiency in the general population, including identification of risk factors including obesity and dark skin tone.
“This study should serve as a wake-up call to orthopedists that vitamin D deficiency is widespread, not necessarily tied to age, sex or background and screening for it should be part of routine pre-surgical care for adults,” said Dr. Lane. “Meanwhile, patients who are planning to undergo any orthopaedic procedure can request a screening (specifically, a blood test called the 25 hydroxy Vitamin D test) or ask to be placed on a medically supervised Vitamin D supplement regimen prior to surgery.”
Study specific details: In a retrospective chart review, Dr. Lane and his colleagues measured Vitamin D levels of 723 patients who were scheduled for orthopaedic surgery between January 2007 and March 2008 and determined the prevalence of normal, insufficient and deficient levels according to the following parameters:
•Normal: equal to or greater than 32 nanograms per milliliter (ng/mL)
•Insufficient: less than 32 ng/mL
•Deficient: less than 20 ng/mL
How much Vitamin D does the skin make? Our skin makes a lot of Vitamin D when we spend time in strong sunlight. With about 5-30 minutes of sunlight exposure of head, face, hands, arms, or legs), our skin can make about 1000 IUs of Vitamin D (Vitamin D is measured in units called “International Units,” or IUs.) Vitamin D is therefore known as “the sunshine vitamin.” However, as you age you can lose your ability to manufacture Vitamin D through sunlight.
How much Vitamin D is enough? The American Academy of Orthopaedic Surgeons (AAOS) and recent research support that the body needs at least 1000 IU per day for good health — depending on age, weight, and growth. Indeed, many people need much more than 1000 IU to keep Vitamin D levels in a good range.
In general, babies (especially mothers who are breastfeeding) and small children should intake at least 400 IU of Vitamin D daily. Children over age 5, adolescents, and adults should get a minimum of 1000 IU of Vitamin D each day. Disclosure: The HSS study was supported by funding from the Cohn Foundation and the Weill-Cornell Clinical Translation Science Center (UL1RR024996-01). Dr. Lane and his co-authors received no compensation for their research.
By Irene Lane, DC Healthy Living Examiner March 4, 2010
Vitamin D deficiencies among young people are more prevalent than one would think. If you adhered to medical advice and shunned the sun for most of your adult life or maintained a strict vegetarian diet, you may be at risk for a vitamin D deficiency. Increasingly, research is revealing the importance of vitamin D as protection against a host of health problems including cardiovascular disease, cognitive impairment, asthma and cancer. Are you at risk?
Dr. Mary Wilkinson, an oncologist / hematologist who practices in Northern Virginia and who has been consistently listed in Washingtonian Magazine as a leading doctor in the Washington, D.C. area says, “The medical community is just realizing that there is a more complex interaction between vitamin D and cellular growth than what has been previously identified. Nonetheless, people who have used sunscreen liberally or have just stayed away from the sun entirely are more likely to have a vitamin D deficiency.”
What are the lifestyle and individual risks for a vitamin D deficiency? Known as the sunshine vitamin, vitamin D is produced by the body in response to sunlight and is essential for strong bones because it helps the body absorb calcium. It is also occurs naturally in a few foods — including fish, egg yolks and fish liver oils as well as in fortified dairy and grain products. But a deficiency can occur for a number of reasons including:
- Following a strict vegetarian diet since the natural sources are animal-based
- Limiting your exposure to the sun
- Having dark skin because the pigment melanin reduces ability to make vitamin D
- Inability for your kidneys to convert vitamin D into its active form
- Inability to absorb vitamin D due to Crohn’s disease, cystic fibrosis or celiac disease
- Having a body mass index of 30 or greater
What are its symptoms? Vitamin D deficiency may be characterized by muscle weakness or bone pain, increased rate of fractures, low energy and fatigue, lowered immunity, symptoms of depression and mood swings and sleep irregularities. Over time, if the deficiency is not detected, osteoporosis, depression, heart disease and stroke, colon or prostate cancer in men, breast cancer in women, diabetes, parathyroid problems, immune system malfunction and weight loss may develop. Dr. Wilkinson adds, “Since we’ve only been measuring vitamin D levels more readily in the last few years, we are unsure if the deficiency causes breast cancer, for example, or if a vitamin D deficiency is merely associated with breast cancer.”
What test confirms the deficiency? The most accurate way to measure how much vitamin D is in your body is the 25-hydroxy vitamin D blood test. In the kidneys, 25-hydroxy vitamin D changes into an active form of the vitamin that helps to control calcium and phosphate levels in the body. Those levels can be measured through the blood test. The normal range is 30.0 to 74.0 nanograms per milliliter (ng/mL). A lower level indicates a vitamin D deficiency. Dr. Wilkinson emphasizes that “being in the middle of the range is very important since we do know that cancer recurrence is associated with both low and high levels of vitamin D. In this case, being in the middle of the range is best.”
How is one treated for the deficiency? Treatment involves getting more vitamin D — through diet, prescription supplements and spending more time in the sun.
How can one prevent the deficiency?
1. Allow yourself limited (no more than 15 minutes) unprotected sun exposure 2. Eat a diet rich in nutrient-dense foods such as fatty fish, egg yolks, fortified organic milk and other dairy products, and organic meats like liver 3. Take a multivitamin that includes fish oil every day 4. Take a vitamin D supplement
By Robert Dominguez
Looks like there’s a scientific reason why “Jersey Shore’s” tan addicts “The Situation” and Pauly D are constantly on the prowl.
Sunbathing boosts the male sex drive.
That’s according to researchers in Austria, who found that testosterone levels in men rise at the same rate as doses of vitamin D, reports Britain’s Daily Telegraph.
Scientists at the Medical University of Graz discovered that men with more vitamin D in their blood had more testosterone than men with less levels of the main male sexual hormone.
Stimulated by exposure to the sun, 90% of vitamin D in the body is produced by the skin. According to telegraph.co.uk, the new study confirms earlier research that just one hour of sunshine can pump up a man’s testosterone level by nearly 70%.
That doesn’t mean that men looking to lift their libidos should go light on the sunblock – you can also get a healthy dose of vitamin D by eating oily fish and meat.
Sharp rise in problem blamed on kids indoors playing computers and parents using too much sunscreen
By Owen Bowcott January 22, 2010
Computer-obsessed children who spend too long indoors and over-anxious parents who slap on excessive sunscreen are contributing to a sharp rise in cases of the bone disease rickets, doctors are warning.
Vitamin D deficiency, which causes the condition, could be rectified by adding supplements to milk and other food, a research team at Newcastle University suggests.
There are several hundred cases of the preventable condition among children in the UK every year, according to a clinical review paper in the British Medical Journal by Professor Simon Pearce and Dr Tim Cheetham.
“More than 50% of the adult population [in the UK] have insufficient levels of vitamin D and 16% have severe deficiency during winter and spring,” they say. “The highest rates are in Scotland, Northern Ireland and northern England. People with pigmented skin are at high risk as are the elderly, obese individuals and those with malabsorption.”
Most vitamin D is synthesised in the body by absorption of sunlight. Some comes from foods such as fish oil. People with darker skins need more sunlight to top up their vitamin D levels.
One of the main reasons for the reappearance of rickets – once considered a disease of the industrial poor in 19th-century cities – is the changing ethnic makeup of the population, Pearce explained.
The most commonly affected are people of Asian or African descent who live in northern cities. He has examined cases among young Somali speakers who live in east Newcastle. But changing lifestyles are also contributing to lowering vitamin D levels in the general population.
“Some people are taking the safe sun message too far,” Pearce said. “It’s good to have 20 to 30 minutes of exposure to the sun two to three times a week, after which you can put on a hat or sunscreen.
“Vitamin D levels in parts of the population are precarious. The average worker nowadays is in a call centre, not out in the field. People tend to stay at home rather than going outside to kick a ball around. They stay at home on computer games.”
Pearce has written to the Department of Health proposing that vitamin D is added to milk. It is already added as a supplement to artificial baby milk. He has also asked the Royal College of Paediatrics to record cases of rickets but said figures were not being collected.
“A more robust approach to statutory food supplementation with vitamin D (for example in milk) is needed in the UK,” the paper concludes.
Meanwhile, figures obtained by the Tories show the number of patients leaving hospital with malnutrition has hit record levels in the last year. Those affected are primarily elderly people. The NHS figures show that last year 175,000 people were malnourished on entry to hospital but nearly 185,500 were in a similar condition on discharge, meaning more than 10,000 patients were more malnourished after medical treatment.
Low levels of vitamin D in lymphoma patients are associated with cancer progression and even death, according to findings from a Mayo Clinic and University of Iowa study reported by ScienceDaily.
“These are some of the strongest findings yet between vitamin D and cancer outcome,” said lead investigator, Matthew Drake, MD, PhD, an endocrinologist at Mayo Clinic in Rochester.
Researchers studied 374 newly diagnosed cancer patients suffering from diffuse large B-cells lymphoma (a fast-growing, aggressive form of non-Hodgkin’s lymphoma) and found half had vitamin D deficiency. Patients deficient in vitamin D had a greater risk of cancer progression and were more likely to die than patients with optimal vitamin D levels.
“The exact roles that vitamin D might play in the initiation or progression of cancer is unknown, but we do know that the vitamin plays a role in regulation of cell growth and death, among other processes important in limiting cancer,” Drake said.
These findings support the growing connection between vitamin D and cancer risks and outcomes as well as reinforce other field research about the vitamin’s overall health benefits, Drake added.
Vitamin D is obtained from sunlight and converted into its active form by the skin. It is also found in food (naturally or fortified as in milk) and is available in supplement form.