Vitamin Information Center

VITAMIN D: “The Sun Vitamin”

Nicholas H.E. Mezitis MD and Despina Komninou MD, PhD, CNS

Did you know that vitamin D, as a hormone, has an important role in metabolic harmony?

Recent studies have shown that vitamin D in its active form is vital for bone health, since it ensures dietary calcium absorption, and helps prevent heart disease, cancer (breast, prostate, lung and colon ), as well as many other illnesses such as diabetes mellitus, rheumatoid arthritis, psoriasis, multiple sclerosis and tuberculosis.

Vitamin D regulates the calcium and phosphorus levels in the blood by promoting their absorption from food in the intestinal tract and by limiting the excretion of calcium by the kidneys. It influences the cells involved in remodeling bone (osteoclasts and osteoblasts) and it inhibits the secretion of parathyroid hormone, which signals calcium release from bone matrix. Importantly, it has a role to stimulate the immune system, promoting phagocytosis and anti-tumor activity among other functions.

The body produces vitamin D when bare skin is exposed to the sun, hence the term �sun vitamin�. Exposure to sunlight for at least 15 minutes two to three times a week produces adequate quantities of this vitamin for the body�s needs. It is estimated that the body can produce more than 20000 IU (international units) of vitamin D with just 20 minutes of sun exposure.. Once adequate amounts of vitamin D have been formed the body, excess amounts formed are rapidly degraded to protect from overload, in the event of prolonged exposure to the sun. However, conditions such as cloudy skies, northern climates, and atmospheric pollution, limit solar ultraviolet radiation exposure and restrict our ability to replete vitamin D stores.

Vitamin D can also be obtained from dietary sources. It is lipid-soluble and is therefore stored in fat. That is why we find it in fatty fish (like salmon and tuna), eggs, cod-liver oil and fortified milk. In our daily diet, 3 servings of milk (about 250 ml) provide us with approximately 900 mg of calcium and 300 IU of vitamin D.

The recommended daily intake (RDI) of vitamin D is 200 IU for infants, youths and adults up to the age of 50 years. The requirement increases to 400 IU for adults ages 51 to 70 and to 600 IU for people older than 70 years. The RDI and the normal reference values for vitamin D in the blood, are based on levels reported to the prevent rickets and osteomalacia, the two main diseases attributed to lack of this vitamin. Rickets is a childhood disease characterized by poor growth and bone weakness, while osteomalacia is the clinical expression of vitamin D deficiency in adults and is characterized by demineralized bones, fractures, bone pain and generalized weakness. Osteoporosis represents abnormal weakening of bone structure with demineralization of the skeleton, and may also be associated with low levels of vitamin D.

Recent studies confirm that optimal vitamin D status is achieved when the 25- OH vitamin D level in the blood is more than 30 ng/ml. Levels between 10-30 ng / ml represent vitamin D insufficiency (hypovitaminosis D) which can either be moderate (21-30 ng/ml) or severe (10-20 ng/ml). Vitamin D levels below 10 ng/ml are considered vitamin D deficiency and have serious consequences. We now know that long before the full clinical presentation of painful osteomalacia, hypovitaminosis D may cause non-specific symptoms such as persistent musculoskeletal pain regardless of age, gender and ethnic origin.

It is worth noting, that a significant proportion of the population has insufficient levels of vitamin D, mainly due to lack of sun exposure, especially during the winter months, which is not compensated by the usual diet. Indeed, today many of us work in buildings with sealed and tinted glass windows and drive everywhere with very few opportunities to walk in the sunlight. During our limited sun exposure opportunities we frequently use a sun screen lotion further obstructing the beneficial effects of sunlight. In areas above 40˚ latitude (e.g. New York, Northern California), sunshine adequate for vitamin D synthesis in the skin is restricted to the months from May through September. Therefore, a large proportion of the population in the United States is at increased risk for vitamin D deficiency

The prevention of hypovitaminosis D has important public health implications. Millions of health care dollars are spent in dealing with the illnesses and complications associated with this problem and additional funds are lost due to curtailed productivity on a societal level. Since sun exposure has its limitations, the diet is our primary source for this vitamin to ensure an intake of at least 1000 IU daily.

The proper diet must be rich in fatty fish such as salmon, mackerel and sardines, mushrooms (Shitake, sun dried, provide 1600 international units per 100 grams), free-range eggs and fortified milk products. Supplementation of vitamin D and calcium is advisable, especially for children and the elderly. Finally, regular, weight-bearing exercise ensures that calcium absorbed through the activity of vitamin D is used to mineralize the skeleton. Similar to a musical composition, health is ensured through harmony in diet and exercise.

More on the maintenance of metabolic harmony will be discussed in our next article *.

* This article is part of medical communication produced by the MEZITIS EDUCATION AND RESEARCH INSTITUTE for the print media, television and radio programs(Cosmos FM “����� ��� ���” every Saturday at 12:30 pm on 91.5 FM and the internet, live streaming, at gaepis.org) focusing on topics in general health, metabolism and nutrition.

By Maureen Williams, ND

Healthnotes Newswire (September 11, 2008)—People with digestive diseases, such as ulcerative colitis and Crohn’s disease, are especially susceptible to osteoporosis and bone fractures, due in part to nutrient deficiencies caused by malabsorption and medication side effects. A new study found that people with good vitamin D status early in the course of their disease had higher bone density and a greater likelihood of increasing bone density over time.

Healthy vitamin D levels predict healthy bones

The study, published in the American Journal of Gastroenterology, included 101 people who had recently been diagnosed with inflammatory bowel disease (IBD). Vitamin D levels in the blood and bone mineral density were measured at the beginning of the study, and bone density measurements were repeated approximately two years later.

Only 22% of the people had optimal vitamin D levels at the beginning of the study. Higher vitamin D levels were associated with higher bone density in the spine, hip, and total body. People with better vitamin D status were more likely than others to have an increase in bone mineral density over the course of the study.

The link between IBD and bone density

IBD is a group of inflammatory conditions affecting the large and small intestines. Ulcerative colitis and Crohn’s disease are the most common types, both of which are believed to be autoimmune (when the immune system attacks the body’s cells) in nature. People with IBD usually experience chronic abdominal pain and diarrhea, often with bleeding and mucus.

In people with IBD, inflammation in the bowel wall and diarrhea compromise absorption and result in nutrient deficiencies. In addition, corticosteroid medicines that are used to treat IBD can interfere with calcium absorption and metabolism. Maintaining healthy bone density requires the integrated work of a number of nutrients, including calcium and vitamin D, so it is not surprising that people with IBD have high rates of low bone density (osteopenia and osteoporosis).

Improving vitamin D status

Vitamin D is made in the body through a series of chemical reactions that begins in sun-exposed skin. Modern lifestyles with limited outdoor time and widespread use of sunscreens have led to increasing rates of vitamin D deficiency in the general population, and these rates are even higher in the elderly and people with chronic disease.

“Poorer vitamin D correlates with lower baseline bone mineral density and better vitamin D status is correlated with a gain in total bone mineral density. Early optimization of vitamin D may play an important role in preventing IBD-related bone disease,” said the researchers from the University of Manitoba in Winnipeg. Small amounts of vitamin D are found in eggs and fish, as well as fortified dairy foods and some dairy substitutes, but the authors noted that their findings suggest that adding vitamin D supplements is warranted for most people with IBD.

A slew of recent books and studies have touted the benefits of vitamin D and the perils of not getting enough vitamin D; some even encourage lying in the sun and taking vitamin supplements in order to prevent depression. But dermatologists say more time soaking up the rays isn’t necessary—most Americans get all the vitamin D they need just by going outside in the course of their daily duties, and beyond that, it’s easy to get adequate levels of the vitamin through nutrients in food. “Sunlight helps us produce vitamin D, but the amount of sunlight you need is so low that you could walk outside for probably five minutes and have enough,” says Craig Austin, a New York-based dermatologist and founder of AB Skincare.

Vitamin D is important because it helps with calcium absorption; it’s found in foods ranging from milk and cheese to liver, beef, fish and eggs. Many cereals are now fortified with vitamin D, as well; most people who follow normal diets probably don’t need to take vitamin D or calcium supplements, Austin says. “Vitamin D deficiency, I don’t think, is really all that common.”

During the winter, people who live in northern climates might consider taking daily supplements, says New Jersey-based dermatologist Eric Siegel. But overdoing the vitamins has side effects, too, including nausea, vomiting, poor appetite and constipation. “You can also start suffering kidney disease, and, believe it or not, once you go past a certain dose of vitamin D, you can start clogging up the kidneys, because there’s too much calcium absorbed into the blood,” he says.

So don’t use vitamin D as a reason to lie in the sun that extra half hour, Siegel says. “Why not get [vitamin D] out of food or supplements?” he asks. “Why give yourself skin cancer?”

DEAR DR. DONOHUE: I am a 76-year-old female. Until December 2005, I thought I was in fairly decent health. That’s when I suffered a fractured hip. I didn’t fall, just sort of slipped down. I have recovered and feel great, and I exercise. Last April, my doctor prescribed 50,000 IU vitamin D once a week. I have been taking it ever since. I get lots of sun. I also take 600 mg of calcium with 200 IU vitamin D twice a day. And I take one multivitamin a day, a Centrum Silver. My doctor wants me to consider taking Fosamax. What’s going on? I worry about getting too much vitamin D. How does a person know how much is too much?

— T.W.

Most adults get too little vitamin D. The official recommendation for daily vitamin D intake is 200 IU for those from 19 to 50, 400 IU for those between 51 and 70, and 600 IU for those 71 and older. Many experts believe these recommendations are insufficient and that the daily dose should be 800 IU to 1,000 IU. Vitamin D enhances calcium absorption and plays a critical role, therefore, in keeping bones strong and in preventing fractures. There are hints that vitamin D prevents osteoarthritis, lessens the risk of prostate cancer and helps prevent diabetes and heart disease. Time will tell if all this is true. The stuff about bones is true.

We get vitamin D when sunlight strikes the skin. It turns a substance in the skin known as a “provitamin” into vitamin D. Ten minutes of sunlight on the face and arms, three times a week to daily, is all the sunlight needed for this conversion. Older people’s skin is not so efficient in making the vitamin, and those living in northern latitudes can’t depend on sunlight conversion in the winter months.

From your weekly 50,000 IU tablet, you get about 7,000 IU of the vitamin daily. Centrum Silver has 500 IU. You get another 400 IU with your daily calcium tablets. So your daily intake is around 8,000 IU. Too much vitamin D can be a problem. It can damage the kidneys and can actually draw calcium from the bones. The upper daily limit is set at 10,000 IU. You haven’t crossed the border, but you’re in its neighborhood. The 50,000 IU tablet can correct a vitamin D deficiency in six to eight weeks. I’d say you’ve made that correction. Ask your doctor about stopping this high-dose vitamin therapy. If there is a question about the adequacy of your body store of vitamin D, a blood test can determine if it is too low, too high or just right.

DEAR DR. DONOHUE: Our 21-year-old daughter has been diagnosed with peripheral neuropathy. Her finger turned a shade of blue. She went to the emergency room and got the diagnosis there. What kind of doctor should we consult to determine if this is her condition?

— V.C.

Your family doesn’t have a history of having peripheral neuropathy, right? So let’s remove all the genetic causes of it from consideration.

Twenty-one is young to come down with it. It’s more of an older person’s illness. People with diabetes and a few other diseases also are targets for it, but your daughter is in otherwise good health.

A blue finger isn’t a usual sign. Your daughter should see a neurologist or a vascular specialist to confirm this diagnosis, which appears a bit strange to me.

Readers may write to Dr. Donohue or request an order form of available health newsletters at P.O. Box 536475, Orlando, FL 32853-6475. Readers may also order health newsletters from www.rbmamall.com.

You are female, over 50, post-menopausal and you keep breaking bones. In fact, you need a hip or knee replacement. The diagnosis? Most likely, your problem will be blamed on osteoporosis.

But the real reason you have brittle bones could be a vitamin D deficiency.

In a recent review of women with osteoporosis hospitalized for hip fractures, 50 percent were found to have signs of vitamin D deficiency, according to Dr. Kenneth Mathis, chairman of orthopedic surgery at the Methodist Center for Orthopedic Surgery in Houston, Texas.

It isn’t only older women who are suffering due to the deficiency. “I am seeing many active, young women and men who have dangerously low vitamin D levels,” said Dr. Mathis.

Osteoporosis is a condition characterized by abnormally porous bone that is fragile and tends to be compressible like a sponge, rather than strong and dense like a brick. In the U.S., more than 10 million people have osteoporosis and an additional 34 million more have low bone density.
The bone disorder is a serious health problem in the U.S. In fact, 50 % of white women will experience a bone fracture due to osteoporosis in her lifetime and 20 % of those who experience a hip fracture will die within a year of the fracture.

A long-term deficiency of vitamin D contributes to osteoporosis because it reduces calcium absorption. The vitamin regulates the amount of calcium that remains in the blood and how much moves into bones and teeth. In addition, vitamin D has also has been found to reduce the risk of breast, colon and ovarian cancer.

“I believe if these people begin taking the daily recommended amount of vitamin D when they are younger, and get their levels tested regularly, that they might be able to prevent osteoporosis and certain cancers when they get older,” Dr. Mathis stated.

Sources of vitamin D include fortified milk, cod liver oil, certain fish (sardines, tuna, salmon and mackerel), yogurt and sunlight. Unfortunately, people who wear a sunscreen with a SPF of 8 or more may have a difficult time converting sunlight into vitamin D.

According to Dr. Mathis, most adults over age 50 should take a daily supplement of vitamin D, if they don’t think they are getting the daily recommended amount (adults under age 50, including pregnant women, need 200 IU of vitamin D daily, people over age 50 need 400 IU daily and those over 70 need 600 IU per day).

However, taking too much vitamin D is not a healthy idea. Dr. Mathis noted the correct amount is important because vitamin D is stored in the liver and in fatty tissues. The vitamin is not water soluble like B vitamins or vitamin C so it cannot leave the body as easily if taken in excess. Vitamin D in very high dosages can build up too much calcium in the blood, leading to kidney stones and/or kidney failure.

One of Dr. Mathis’ patients, sixty-year-old Darlene Yates, was found to have a vitamin D deficiency and she has begun a strict vitamin D regimen to build up her levels following several episodes of broken bones.

She reports her energy has improved and she feels better in general after the treatment.
“I’m hoping that I can get to where I don’t break any more bones and have to have any more surgeries,” Yates said. “If I would have known about the link between vitamin D and bone weakness 40 years ago, you can bet I would have done something about it.”

Sixty-year-old Darlene Yates has had two hip replacements, a knee replacement and this past year shattered her left femur while she was walking in her neighborhood. Her diagnosis seemed obvious — osteoporosis. But it turns out she had bone weakness caused by a vitamin D deficiency.

“I thought with my age and all my broken bones that I definitely had osteoporosis,” Yates said. “The low vitamin D levels really took me by surprise.”

Vitamin D promotes the absorption of calcium and phosphorus. It regulates how much calcium remains in the blood and how much makes its way to the bones and teeth. It also has been found to reduce the risk of breast, colon and ovarian cancer. Vitamin D deficiency contributes to osteoporosis by reducing calcium absorption and osteoporosis is an example of the long-term effects of vitamin D deficiency.

In a recent review of women with osteoporosis hospitalized for hip fractures, 50 percent were found to have signs of vitamin D deficiency. Low levels are most often seen in older women; however, times appear to be changing.“I am seeing many active, young women and men who have dangerously low vitamin D levels,” said Dr. Kenneth Mathis, chairman of orthopedic surgery with The Methodist Center for Orthopedic Surgery. “I believe if these people begin taking the daily recommended amount of vitamin D when they are younger, and get their levels tested regularly, that they might be able to prevent osteoporosis and certain cancers when they get older.”

Sources of vitamin D include fortified milk, cod liver oil, fish such as sardines, tuna, salmon and mackerel, some yogurt and breakfast cereals, and the sun. However, if you wear an SPF of eight or more, you will have a tough time converting the sunlight into vitamin D.

Most adults over age 50 need to take a daily supplement of vitamin D if they don’t think they are getting the daily recommended amount. Adults under age 50, including pregnant women, need 200 IU of vitamin D daily. A person over age 50 needs 400 IU daily and it goes up to over 600 IU at age 70.

Mathis says taking the correct amount is important because too much vitamin D can be toxic. Vitamin D is stored in the liver and in the fat tissue. When you take too much it cannot leave the body as easily as water soluble vitamins such as vitamin C. The excess vitamin D can lead to too much calcium in the blood, which can cause kidney stones and/or kidney failure.

Yates has begun a strict vitamin D regimen to build up her levels. She says she has more energy than she ever has and is feeling better.

“I’m hoping that I can get to where I don’t break any more bones and have to have any more surgeries,” Yates said. “If I would have known about the link between vitamin D and bone weakness 40 years ago, you can bet I would have done something about it.”

DR. DAVID WONG
The Guardian

Question: I am the mother of three lovely children. When our third child was born six weeks ago, our family doctor told me that I should give him vitamin D everyday because I am breast-feeding him.

I breast-fed our two older children but I never gave them any vitamin D, and they are perfectly fine. I wonder whether I should follow our doctor’s suggestion.

Answer: Your doctor is correct, you should give him vitamin D 400 international units (IU) a day because you are breast-feeding him. Recent research shows that many children and adults in Canada are not getting enough Vitamin D, and this can affect our health.

Vitamin D is normally produced in our skin when it is exposed to ultraviolet light rays from the sun. If a white-skinned person in a bathing suit is exposed to summer sun around noon time for 15 to 20 minutes, about 10,000 IU of vitamin D will be produced by the skin. However, if a dark-skinned person is exposed to the sun in the same way, only about 2,000 IU of vitamin D is being produced.

Melanin, a dark pigment present in the skin, blocks the ultraviolet rays. As a result, less vitamin D is produced. In the same way, if we put on sunscreen lotion or wear long-sleeve shirts and long pants to prevent sunburn, the amount of vitamin D produced in the skin also decreases.

Vitamin D is best known for the growth and development of bones in children. The importance of vitamin D was first discovered in England in the mid-17th century. Physicians at that time saw young children with bone deformities they called rickets. They recognized rickets was most common during winter months and they suspected a link between rickets and exposure to sunlight.

Over time, cod-liver oil was found to be effective in the prevention and treatment of rickets. As a result, vitamin D was discovered and was shown to be important for calcium absorption from the intestines and deposition in the bones.

Because of the importance of vitamin D in the prevention and treatment of rickets, all cow’s milk (except yogurt drinks), soy milk and some orange juice sold in North America are fortified with vitamin D. For a long time, many people, including physicians, thought that these measures had eradicated rickets completely.

In 1984, several Canadian researchers reported 16 Inuit infants living in high Arctic coastal communities with vitamin D deficiency rickets. This report rekindled interest in vitamin D and the fact that rickets still occurs in spite of years of fortification of cow’s milk and other products.

In 2007, another group of researchers reported a two-year study which identified 104 children across Canada with rickets due to a lack of vitamin D in their diet. Most of these children lived in the far north, many were breast-fed and had no vitamin D supplement given to them. Their mothers also lacked vitamin D because of limited exposure to the sun and did not have enough vitamin D from their diet or supplementation during pregnancy and while they were nursing.

These findings highlighted the importance of lack of sun exposure for Canadians, especially during the fall and winter months, and a deficiency of vitamin D in the body. Unless the diet is rich in vitamin D, supplementation is necessary to prevent a vitamin D deficiency state.

Aboriginals have changed their diet in recent years. They used to hunt and fish and stay active outdoors much of the time. Their source of food used to have good amount of vitamin D. However, with a more westernized diet, their intake of vitamin D has decreased.

Although breast milk is the most natural and nutritious food for babies, it does not contain enough vitamin D unless the mother’s vitamin D level is high, either from lots of sun exposure or taking significant amount of vitamin D (from food or supplements, or both) during pregnancy and breast-feeding.

Because of these findings, the Canadian Paediatric Society now recommends that all breast-fed babies should be supplemented with 400 IU of vitamin D everyday during the first year of life.

For those who live in areas further north than approximately Edmonton, Alta., the amount of vitamin D required from all sources should be increased to 800 IU per day between October and April.

It is also recommended that pregnant and breast-feeding women should receive 2,000 IU of vitamin D a day. This recommendation is based on the lack of sunshine in Canada, as well as the importance of vitamin D in the development of bones and other organs in babies before and after birth.

Recent research also suggests vitamin D is important for most parts of the body, not only for bones. All chemicals interact with cells in the body through receptors, which are like doors that allow chemicals to enter cells. Most cells in the body have vitamin D receptors, which means that vitamin D is important in the function of most cells in the body.

A number of medical conditions have been linked to a lack of vitamin D. These include osteoporosis, asthma, rheumatoid arthritis, multiple sclerosis (MS), inflammatory bowel diseases (Crohn’s disease and colitis), diabetes, disturbed muscle function, tuberculosis and several types of cancer. Many of these diseases are much more common in countries like Canada and northern Europe.

Because of recent research findings, the Canadian Cancer Society recently recommended that all white adults take 1,000 IU of vitamin D a day in fall and winter, while non-whites should take this amount year-round.

Most multivitamin pills only have 400 IU of Vitamin D, although 1,000 IU vitamins D pills are becoming more available recently.

Although vitamin D is very important for the body in many ways, we still don’t know what is the maximum safe dose that one can take.

More does not necessary mean better or safe. Excessive amount of vitamin D can increase calcium level in the blood and cause calcium deposits in places where it shouldn’t happen.

Until research can answer some of these questions, the safest way is to follow the recommendations of these professional societies. In the meantime, it likely won’t hurt for you to get some natural vitamin D on a sunny day, although this has to be balanced with danger of sunburn and long-term risk of skin cancer.

Dr. David Wong is a consultant pediatrician in Summerside and president of the Community Paediatric Section of the Canadian Paediatric Society. His column is in The Guardian every four weeks. You can find his previous columns at www.askdrwong.ca. If you have a question for Dr. Wong, mail it to: Ask Dr. Wong, P.O. Box 21018, Summerside, P.E.I., C1N 6A1.

It takes more than drinking milk to strengthen our bones. Milk is certainly a good source of calcium, but it is only one option to prevent or retard osteoporosis, the disease that affects one out of every two women over the age of 50.

Bone density begins its slow decline between the ages of 25 and 30. By the age of 70, women can lose up to 30 percent of that density. By age 75, osteoporosis becomes as common in men as it is in women.

Osteoporosis means “porous bones” and is considered the third-leading health issue in our country, after cardiovascular and cancer problems. The most threatening areas for fractures to occur are in the spine, hips and wrists.

When bones become weak and brittle, actions as easy as bending over or even coughing can cause fractures. While hip fractures usually are a result of a fall, many fractures occur without involving any falls.

Compression fractures can develop when bones in your back simply become too weak, resulting in a stooped posture. This will increase pressure around your spine, eventually causing more compression fractures.

Three of the major risk factors for osteoporosis that we can control are lack of regular exercise, too little calcium intake and an inadequate amount of vitamin D, which is essential for calcium absorption.

People who have been physically active in their younger years have an advantage over their non-active friends: While the active types may lose some bone as they age, their chances of suffering fractures from having brittle bones are greatly reduced.

It never is too early or too late to begin strengthening the muscles and the bones. Exercise can improve muscle strength, bone density, posture and balance, all of which will help prevent falls.

If you already have osteoporosis, exercising can help maintain your bone mass. You should replace any high-impact exercise that could place stress on your spine (such as jogging) with more gentle weight-bearing exercises (walking).

Similarly, bending and twisting movements at the waist (such as in golf, tennis and situps) should be avoided, because they could cause the already weakened spinal bones to compress and possibly fracture.

It is important to check with your physician or physical therapist before you begin exercising, because you need to find the safest and most enjoyable exercises depending on your degree of bone loss.

Exercise prevents osteoporosis

Muscles become stronger and bone density increases as you place demands upon them; bone is a living tissue that reacts positively to exercise.

Commitment to consistent exercise is essential, because once you cease exercising, bone density benefits will also cease.

For strengthening and helping to maintain healthy bones, it is recommended to do weight-bearing exercises a minimum of 30 minutes for three days per week and resistance exercises two or three times a week.

What type of exercise is best

Weight-bearing exercises require your body to work against gravity: jogging, brisk walking, stair climbing, racquet sports and dancing are good examples. Swimming and biking, while excellent for cardio workouts, are not considered a weight-bearing exercise.

However, in some stages of osteoporosis, water exercises may be used in rehabilitation. Resistance exercise (strength training) strengthens muscles and bones throughout the entire body. These exercises involve using your muscular strength to work against the weight of another object, such as using free weights, weight machines or resistance bands.

For some resistance exercises, you can even use your own body weight as the exercise load. Balance, coordination and flexibility exercises for fall prevention include standing on one leg, sitting and exercising on an exercise ball, tandem walking, stretching, dancing, tai chi and yoga.

Nutritionally speaking

According to the National Institutes of Health, people with vitamin D deficiencies absorb less than 10 percent of available calcium they ingest. Three of the leading contenders for calcium are plain low-fat yogurt, fruit yogurt and whole, low-fat or fat-free milk.

Our body’s absorb vitamin D through sunlight and vitamin D-fortified foods, such as milk. Here are a few added suggestions to fortify your 206 bones:

• Treat yourself to 15 minutes a day without any sunscreen. That is what your body needs to produce vitamin D, the “sunshine vitamin.”

• Almonds are packed with bone health. A handful counts for about 70mg of calcium.

• Studies indicate that a cup of tea a day increases bone density.

• Eat brown instead of white. Brown rice has three times the calcium than white rice.

• Try having chopped figs over yogurt for a snack; it will give you almost half the needed calcium requirements for the day.

If you are 50 or older and have not been exercising, check with your physician before beginning ANY exercise program. Sally Anderson, a trainer, is happy to hear from readers but cannot respond to individual queries. Write her in care of LifeTimes, St. Petersburg Times, P.O. Box 1121, St. Petersburg, FL 33731.

Hip extensions

Strengthens hips and thighs. Place one hand on a countertop. Keeping hips facing forward, slowly lift one leg out to the side, knee facing forward, as Royce demonstrates at left. Hold a few seconds, then slowly return leg to ankle, never touching the floor. Repeat 8 to 10 times. Priscilla shows the next movement: Lift leg diagonally to the back. Hold, then slowly release leg; repeat 8 to 10 times. Tips: Contract abdominals and do not lock knees. You may add ankle weights later.

Tandem walk

Develops balance. (Not shown.) Stand with fingers lightly supported on a counter or a wall. Looking straight ahead, walk, placing one foot directly in front of other foot, making sure front heel is close to back toes; aim for 15 to 20 steps. Then, if you do not have foot or ankle issues, try walking on your heels, with the balls of your feet lifted up. Tip: Walk tall, do not lean forward.

Wringing the towel

Strengthens the wrist. Hold a towel in both hands, keeping elbows close to your sides. Wring the towel out as hard as you can, extending one wrist and flexing the other wrist at the same time; do 10 to 15 repetitions. Tip: Use your wrist muscles, not your fingers.

Back extension

Strengthens shoulders, back, neck, spine and hips. Begin by lying on your stomach on a mat with arms in front of you, palms facing downward. Keeping legs on mat, lift head, arms and chest off the mat. Bend elbows, bringing them in toward your shoulders, feeling a slight pinch of the shoulder blades. Hold for several seconds, then extend arms to original position and repeat several times. Tip: Do not hold your breath.

Wringing the towel

Strengthens the wrist. Hold a towel in both hands, keeping elbows close to your sides. Wring the towel out as hard as you can, extending one wrist and flexing the other wrist at the same time; do 10-15 repetitions. Tip: Use your wrist muscles, not your fingers.

Seattleites need more vitamin D. We don’t get enough sunshine, says a Kirkland rheumatologist (and pretty much every other physician around).

During the past year, Dr. Richard Neiman tested the vitamin D levels of 145 of his patients. Using blood tests, he found only 39 patients had normal levels. The average age of the patient was about 59, and most were female.

The levels weren’t only low in winter, though, when the sun rarely peeks though the clouds in Seattle. Patients weren’t building levels during summer, either when maximum sunlight shines here, Neiman said. (He suggested vitamin D should be added to the water.)

Often called the “sunshine vitamin,” Vitamin D is made in the body after exposure to ultraviolet rays from the sun. It helps with calcium absorption, key for growing bones and preventing osteoporosis.
A Seattle PI story warned of the need for more vitamin D for Seattlites.

The solution? Vitamins, supplements, move to a different city maybe?

A study by researchers at the Institute for Cancer Research in Oslo, Norway has given further credence to the claim that the benefits of modest sun exposure outweigh the risk of skin cancer for most people. Johan Moan, the researcher who led the study said, “Modest sun exposure gives enormous vitamin D benefits.”

He estimated that doubling the amount of sun exposure for residents of Norway would double the number of deaths due to skin cancer to 300. However, the great benefit to this would be a decrease of 3,000 people who die from other cancers [1].

The human skin synthesizes vitamin D when exposed to the ultraviolet type B (UVB) radiation in sunlight. Solar radiation is the main source of vitamin D for most people. Modest sun exposure causes a significant amount of vitamin D to accumulate in the body and protect from some internal cancers and other illnesses such as diabetes and rickets. Vitamin D promotes bone mineralization and calcium absorption thus protecting against osteomalacia and osteoporosis. The vitamin also helps the body’s immune system function properly [2]. When deficient, the human body is at great risk of acquiring these conditions and deficiency is linked to heart attacks and mental depression. Most people could experience the benefits by increasing their sun exposure, but not too much as to cause any burning.

Vitamin D deficiency has been measured to be as high as 21 to 58 percent in adolescents and adults in the United States [3].

Several factors reduce individuals’ exposure to sunlight and UVB light rays: the amount of time spent in the sun is the most obvious. Also, more polar latitudes, the time of day such as dusk compared to noon, high cloud cover, smog, and sunscreen use lower the amount of UVB radiation that reaches people.

Geographic latitude plays a significant role. Generally, the farther an individual is from the equator, the more difficult it is to synthesize enough vitamin D. For example, in Boston, MA, from November through February, the average amount of sunlight is inadequate for an individual to synthesize enough vitamin D [4]. Additionally, the researchers at the Institute for Cancer Research in Oslo determined that, given the same amount of sunlight, inhabitants of Australia just below the equator produced 3.4 more times the vitamin D than people in Britain and 4.8 times that of Scandinavians [1].

It’s essential to learn the optimal amount of sun exposure that is healthy for you without causing sunburn. Moan recommended that a person’s daily sun exposure should be about half the time that it would take to burn. Lighter skinned people are more sensitive to sunburn and skin damage, but they are more proficient at creating vitamin D with less sun exposure than a darker skinned person (Please see [5] below for a related, generally accepted theory for skin color variance). Light skinned peoples in Southern United States can synthesize enough vitamin D by exposing their face and arms to the sun without sunscreen for about 15 minutes a few times a week. Dark skinned people need about 5 to 10 times more exposure [2].

A consensus has not been made for how much vitamin D is a healthy level for most people, but it’s generally agreed that for people up to the age of 50, 200 IUs (international unit) is the Adequate Intake (AI). For 51 to 70 year olds, 400 IUs is the AI and for individuals over 70, 600 IUs is recommended. The ability to synthesize vitamin D decreases with age. However, recent studies have shown amounts of vitamin D of 2,000 IUs and higher to be more effective and still safe [6]. If a person works outside under the summer sun for hours in a tank-top and shorts, his skin will have made thousands of IUs. Of course, a baseline tan to prevent burning would be a good idea. Normal body levels of vitamin D can’t reach the level that a large vitamin D pill would produce. The body self-regulates; reducing vitamin D synthesis when levels are getting high from sun exposure.

Is there a difference between taking say, 1,000 IUs in pill form and synthesizing it via UVB radiation? Is putting a 1,000 IU pill in your body versus forming it all over your skin comparable to drinking 8 glass of water at once versus spreading it throughout the day? This, I am unsure of.

Within UVB light are a range of wavelengths. Some are more optimal for vitamin D synthesis than others. A person at sea level will receive these wavelengths when the sun is 45 degrees above the horizon or the UV index for the day is above 3. When the sun is at or above this elevation in the sky, sufficient amounts of vitamin D can be made by the skin in about 15 minutes a few times a week. The area of the planet within the tropics provides this solar elevation daily, but it occurs daily only in the spring and summer seasons of temperate regions, and nearly never in the arctic circles [7]. Seasonal supplementation seems to be appropriate.

Sunscreen with a sun protection factor (SPF) of 8 prevents more than 95% of vitamin D production [11]. So when you lather up with this sunscreen, it will take 20 times longer than usual to make enough vitamin D. This effect was observed during a campaign in Australia to increase sunscreen use to prevent skin cancer. The result was an increase in Australians with vitamin D deficiency [8].

If the minimum level of sun exposure can not be obtained, people should look to their diet for vitamin D. Since few foods contain enough vitamin D, some foods are fortified with vitamin D and supplements can be taken to attain an adequate level.

To complicate matters further, there are 5 forms of vitamin D. The two major forms are vitamin D2 (ergocalciferol) and D3 (cholecalciferol). Both forms are present in human nutritional supplements. When our skin comes into contact with UVB radiation, it synthesizes only vitamin D3. Both of these forms are prohormones, precursors to the vitamin D hormone that goes on to perform all of the beneficial processes that have been mentioned. However, the vitamin D3 form is about 3 times more effective at creating the vitamin D hormone and its duration of action is longer that the D2 form. Supplementing with vitamin D3 would be the wiser choice [9].

UVA and UVB radiation exposure is a double edged sword. Excessive exposure will cause damage to the skin and more importantly, to the DNA inside the cells. With more DNA damage comes a greater chance of developing skin cancer. However, only a small percentage of skin cancers are the type that will metastasize (to spread throughout the body from the origin of formation). The wavelengths of UVA light are longer and penetrate farther into the skin. UVA radiation is a more potent cause of skin cancer than the shorter UVB light.

Skin cancers are among the fastest growing types of cancer in the United States and make up about 1 out of 3 new cancers.

With the rise in popularity of sun bathing, something must be said about tanning beds. Although the time spent in a tanning bed is typically much less than say, an afternoon at the beach, the radiation levels are more intense than from sunlight and the UVA to UVB radiation ratio is much higher than from the sun. The amount of UVA radiation in the light of tanning beds is typically between 3 to 8 times greater than in sunlight [10]. Recall that UVA radiation, and UVB less so, put individuals at risk for DNA damage and skin cancer, but only exposure to UVB radiation will produce vitamin D, which protects against many illnesses. Therefore, it is this author’s humble opinion that, while tanning beds may be more convenient, it is safer to get your healthy glow from the sun and good nutrition.

References:

[1]“Addressing the health benefits and risks, involving vitamin D or skin cancer, of increased sun exposure”((http://www.pnas.org/cgi/content/abstrac…)

[2]((http://www.medicinenet.com/script/main/…)

[3]“Vitamin D Deficiency-The Once and Present Epidemic” (http://www.aafp.org/afp/20050115/editorials.html)

[4](http://healthlink.mcw.edu/article/982088787.html)

[5]“Skin Color Adaptation” (http://anthro.palomar.edu/adapt/adapt_4.htm)

[6](http://www.vitamindcouncil.com/treatment.shtml)

[7]((http://upload.wikimedia.org/wikipedia/c…)

[8]Nowson C, Margerison C (2002). “Vitamin D intake and vitamin D status of Australians”. Med J Aust 177 (3): 149-52. PMID 12149085.

[9]“Vitamin D2 Is Much Less Effective than Vitamin D3 in Humans” ((http://jcem.endojournals.org/cgi/conten…)

[10]Woollons, A., Clingen, P.H., Price, M.L., Arlett, C.F., Green, M.H.L. (1997). Induction of mutagenic DNA damage in human fibroblasts after exposure to artificial tanning lamps. British Journal of Dermatology 1997; 137: 687-692.

[11]((www.motherearthnews.com/Natural-Health/…)