Vitamin Information Center

The human body is an amazing factory, with all kinds of parts working together to make chemicals necessary for good health. But one thing it can’t make on its own is vitamin D. Research shows that defect can be troubling, especially among children.

To create vitamin D, which plays an important role in bone health and development, the body needs exposure to sunlight. As some countries move into autumn, the days get shorter and colder and exposure to sunlight decreases, making the colder months of the year a crucial time to watch vitamin D intake. Supplements can play an important role but one question is, how much?

Most of a child’s bone mass is built up early. A vitamin deficiency can prevent a child from building adequate bone mass now, and they won’t be able to make it all up later.

Although a study released this week found that vitamin D deficiencies are common in children around the world, there is minimal data on how much supplementation is necessary or safe.

Vitamin D is a fat — soluble vitamin directly or indirectly involved in several key body processes: regulating calcium and phosphorus levels in the blood, promoting bone formation and mineralisation, restricting parathyroid hormone secretion and promoting anti-tumour activity.

A review of medical literature on the vitamin published last year in The New England Journal of Medicine found that vitamin D is also associated with a reduced risk of type 1 diabetes in children, and may inhibit future hip fracture.

The main source of vitamin D is sunlight, which the body uses to convert vitamin D into a useable form. It’s also found naturally in eggs and fatty fish like salmon or tuna, and milk and some breakfast cereals are fortified with the vitamin.

The Institute of Medicine recommends that children get 200 IUs of vitamin D daily, but some experts say that up to 800 IUs is better.

The new study found that high doses of the vitamin were safe for children, whether taken over the short-term or for a longer period of time, and helped increased bone mass in 10 to 17 year olds.

A study released this summer found that even children who are otherwise healthy can have low levels of vitamin D, resulting in low levels of bone mineral content.

The risk for low vitamin D levels begins in infancy —breast milk, like cow’s milk, is naturally low in vitamin D. And if a mother doesn’t have enough vitamin D, her breast milk won’t either.

A vitamin D deficiency can affect bone growth even if there are no obvious problems.

A bottle of vitamin supplements
The American Academy of Paediatrics says that rickets, bone softening that can lead to fractures and deformity, in infants due to low vitamin D intake is seen in several US states.

The agency recommends that breast-fed infants receive vitamin D supplement drops.

Children at risk
“It is recommended that all infants, including those who are exclusively breastfed, have a minimum intake of 200 IUs of vitamin D per day beginning during the first two months of life,” said a clinical report for the health agency done by Dr Lawrence Gartner and Dr Frank Greer.

“In addition, it is recommended that an intake of 200 IUs of vitamin D per day be continued throughout childhood and adolescence, because adequate sunlight exposure is not easily determined for a given individual.”

The risks to bone health don’t end in infancy.
A Canadian study released last year found that despite guidelines for its prevention, vitamin D-deficiency rickets in childhood is still seen in the country, with an annual incidence of 2.9 cases per 100,000.

Children living in countries where exposure to sunlight is low had the highest incidence, and most of the affected children had medium to dark skin tones and had been breast fed.

“Since there were no reported cases of breast-fed children having received regular vitamin D (400 IU/d) from birth who developed rickets, the current guidelines for rickets prevention can be effective but are not being consistently implemented,” the study concluded.

Adequate vitamin D levels in the blood are important because the body can’t absorb dietary calcium without vitamin D, so in its absence it steals calcium from the bones, which increases the risk of rickets, osteoporosis and fractures.

This also places teenagers at risk because they have weaker bones that are more likely to fracture.

Children at particular risk include infants who are breast-fed exclusively and don’t receive supplementation, children who use sunscreen in summer, children who don’t use sunscreen in the summer but spend less than 15 minutes a day in direct sunlight, children who receive no supplementation in the winter, and children with chronic diseases that affect fat malabsorption, such as cystic fibrosis or celiac disease, according to the Hospital for Sick Children.

TORONTO (Reuters) - The human body is an amazing factory, with all kinds of parts working together to the make the chemicals necessary for good health. But one thing it can’t make on its own is vitamin D. Research shows that defect can be troubling, especially among children.

To create vitamin D, which plays an important role in bone health and development, the body needs exposure to sunlight. As we move into autumn, the days get shorter and colder and our exposure to sunlight decreases, making the colder months of the year a crucial time to watch vitamin D intake. Supplements can play an important role but one question is, how much?

Most of a child’s bone mass is built up early. A vitamin deficiency can prevent a child from building adequate bone mass now, and they won’t be able to make it all up later. Although a study released this week found that vitamin D deficiencies are common in children around the world, there is minimal data on how much supplementation is necessary or safe.

Vitamin D is a fat-soluble vitamin directly or indirectly involved in several key body processes: regulating calcium and phosphorus levels in the blood, promoting bone formation and mineralization, restricting parathyroid hormone secretion and promoting anti-tumor activity. A review of medical literature on the vitamin published last year in The New England Journal of Medicine found that vitamin D is also associated with a reduced risk of type 1 diabetes in children, and may inhibit future hip fracture.

The main source of vitamin D is sunlight, which the body uses to convert vitamin D into a useable form. It’s also found naturally in eggs and fatty fish like salmon or tuna, and milk and some breakfast cereals are fortified with the vitamin. The Institute of Medicine recommends that children get 200 IUs of vitamin D daily, but some experts say that up to 800 IUs is better.

This week’s study found that high doses of the vitamin were safe for children, whether taken over the short-term or for a longer period of time, and helped increased bone mass in 10-17-year olds.

Vitamin D deficiency is particularly a problem for North Americans, research shows, due in part to the higher latitudes at which they live. As well, because of concerns about skin cancer, many people now wear sunscreen, which inhibits the body’s ability to use sunlight to make the vitamin. The Hospital for Sick Children in Toronto says that sunscreen with an SPF above 8 blocks all vitamin D production through the skin. And darker-skinned individuals living in Canada and the United States may be at particular risk because they have more melanin in their skin, which means they need more sunlight than a lighter-skinned person to make the same amount of vitamin D.

A study released this summer found that even children who are otherwise healthy can have low levels of vitamin D, and resulting low levels of bone mineral content. More than 12 percent of the 400 kids studied by researchers at the Children’s Hospital in Boston had levels of vitamin D in their blood low enough to qualify them as deficient, and 40 percent of the children had less than the recommended level
The risk for low vitamin D levels begins in infancy - breast milk, like cow’s milk, is naturally low in vitamin D. And if a mother doesn’t have enough vitamin D, her breast milk won’t either.

A vitamin D deficiency can affect bone growth even if there are no obvious problems. The American Academy of Pediatrics says that rickets (), bone softening that can lead to fractures and deformity, in infants due to low vitamin D intake is seen in several U.S. states. The agency recommends that breast-fed infants receive vitamin D supplement drops.

“It is recommended that all infants, including those who are exclusively breastfed, have a minimum intake of 200 IUs of vitamin D per day beginning during the first 2 months of life,” said a clinical report for the health agency done by Drs. Lawrence Gartner and Frank Greer. “In addition, it is recommended that an intake of 200 IUs of vitamin D per day be continued throughout childhood and adolescence, because adequate sunlight exposure is not easily determined for a given individual.”

The risks to bone health don’t end in infancy. A Canadian study released last year found that despite guidelines for its prevention, vitamin D-deficiency rickets in childhood is still seen in the country, with an annual incidence of 2.9 cases per 100,000. Children living in the northern part of the country, where exposure to sunlight is the lowest, had the highest incidence, and most of the affected children had medium to dark skin tones and had been breast fed.

“Since there were no reported cases of breast-fed children having received regular vitamin D (400 IU/d) from birth who developed rickets, the current guidelines for rickets prevention can be effective but are not being consistently implemented,” the study concluded.

Adequate vitamin D levels in the blood are important because the body can’t absorb dietary calcium without vitamin D, so in its absence it steals calcium from the bones, which increases the risk of rickets, osteoporosis and fractures. This also places teenagers at risk because they have weaker bones that are more likely to fracture.

Children at particular risk include infants who are breast-fed exclusively and don’t receive supplementation, children who use sunscreen in the summer, children who don’t use sunscreen in the summer but spend less than 15 minutes a day in direct sunlight, children who receive no supplementation in the winter, and children with chronic diseases that affect fat malabsorption, such as cystic fibrosis or celiac disease, according to the Hospital for Sick Children.

Because natural sources are so rare, it’s difficult to get adequate vitamin D in the diet. One tablespoon of cod liver oil has 1,360 IUs, a serving of cooked salmon has 360, a cup of fortified milk has 98 and a whole egg has 20. Fifteen minutes of direct sunlight is enough for many people to reach their needs for vitamin D, but darker-skinned people need longer exposure and because winter sunlight in North America is indirect, supplementation may be recommended.

Do you supplement with extra vitamin D? Let us know: HealthMatters@reuters.com

Healthnotes Newswire (August 28, 2008)—Building and maintaining bone is complex work involving many nutrients, such as calcium, vitamin D, magnesium, boron, vitamin K, and essential fatty acids. A new study found that low levels of vitamins B6 and B12 and high levels of homocysteine were associated with increased risk of hip fracture.

B vitamins, homocysteine, and changes in bone

The study, published in the Journal of Clinical Endocrinology and Metabolism, included 714 senior men and women who were participating in the longstanding Framingham Study. Tests to measure bone density and blood levels of homocysteine, folic acid, and vitamins B6 and B12 were done at the beginning of the study and bone density was measured again after four years.

People with low vitamin B6 levels experienced more bone density loss than people with normal B6 levels, and people with B6 deficiency lost the most bone. Low and deficient levels of vitamins B6 and B12, as well as high levels of homocysteine (a potentially toxic amino acid byproduct), were each independently associated with more hip fractures.

How B vitamins and homocysteine are connected

Folic acid and vitamins B6 and B12 are all involved in the metabolism of homocysteine, and when any of these vitamin levels drops, homocysteine can accumulate, potentially leading to negative health effects. Getting more of these vitamins through diet or supplements can bring down high homocysteine levels. A high homocysteine level is a risk factor for heart disease, and some evidence suggests it might also be a risk factor for a number of other conditions including stroke, clotting problems, inflammatory bowel disease, Alzheimer’s disease, hypothyroidism, death from diabetes, pregnancy complications, and osteoporosis.

Despite their connection, B vitamins and homocysteine appear to have distinct effects on bone loss and fracture risk. “This study suggests that low vitamin B6 status, but not elevated homocysteine, is an important determinant of bone loss in community dwelling elders,” the study’s authors concluded.

Getting more B vitamins

The best way to get more vitamin B6 and folic acid is to eat plenty of fruits, vegetables, whole grains, and legumes. Vitamin B12 is found in animal foods and fish, and possibly sea vegetables and tempeh, a cultured soy food. Eating more of all three of these vitamins, especially folic acid, from food and supplements is a good strategy for reducing high homocysteine levels.

Although vitamin B6 and folic acid are usually readily absorbed, some health conditions can interfere with vitamin B12 absorption, such as gastritis, inflammatory bowel disease, infections of the digestive tract, and any condition that causes malabsorption. People with these conditions might need to take high-potency supplements and should consult their doctor first.

(J Clin Endocrinol Metab 2008;93:2206–12)

Maureen Williams, ND, received her bachelor’s degree from the University of Pennsylvania and her Doctorate of Naturopathic Medicine from Bastyr University in Seattle, WA. She has a private practice in Quechee, VT, and does extensive work with traditional herbal medicine in Guatemala and Honduras. Dr. Williams is a regular contributor to Healthnotes Newswire.

Copyright © 2008 Healthnotes, Inc., dba Aisle7. All rights reserved. Republication or redistribution of the Aisle7 content is expressly prohibited without the prior written consent of Aisle7. Healthnotes Newswire is for educational or informational purposes only, and is not intended to diagnose or provide treatment for any condition. If you have any concerns about your own health, you should always consult with a healthcare professional. Aisle7 shall not be liable for any errors or delays in the content, or for any actions taken in reliance thereon. Aisle7 and the Aisle7 logo are registered trademarks of Aisle7.

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.”

New research has concluded vitamin K2 consumption can aid recovery from hip fractures as well as have potential osteoporosis benefits.

Published in the European Journal of Epidemiology, Japanese researchers found a positive link between vitamin K2 and hip fractures and osteoporosis, and suggested a review of the, “dietary reference value of vitamin K from the perspective of osteoporosis would be useful.”

The current Japanese reference value is 55mcg for women and 65mcg per day for men. In the US and Canada it is 120mcg per day for men and 90mcg per day for women. In France the limit is 65mcg per day for both men and women.

“Since regions which consumed a lot of vitamin K, especially vitamin K2, showed a low incidence of hip fracture, we considered that vitamin K intake, not absorption, of over 300 mcg/day would be helpful to reduce the incidence of hip fracture,” the researchers concluded.

Family K

The vitamin K family includes the forms phylloquinone (K1) that are typically found in cruciferous vegetables and menaquinone (K2), which are sourced from bacteria. Studies have shown K2 to be the more important nutrient in regard to bone health.

“Menaquinone-7 (K2) showed a very long half-life time compared to vitamin K1,” the researchers wrote. With this in mind they recommended higher doses in regions like Europe and North America, where vitamin K1 consumption is higher.

The study also investigated vitamin D, calcium and magnesium, which have strong clinical bone health backing, and found when these were adjusted for, vitamin K2 continued to reveal a beneficial effect.

Dietary sources

The study assessed population diets in various regions of Japan as well as dietary differences, and found that those regions where certain vitamin K-rich fruits and vegetables were prominent had reduced rates of hip fracture.

“There was also a striking pattern of high intake of vitamin K and low incidence of hip fracture in eastern areas of Japan, with the opposite pattern-a low intake of vegetables rich in vitamin K and a high incidence of hip fracture-in western areas,” they wrote.

“These findings lend support to the idea that vitamin K is an important factor explaining regional differences in the incidence of hip fracture.”

Natto, a food made from fermented soy beans, was singled out as being a particularly abundant vitamin K source.

K for bones

The researchers recognised that the role of Vitamin K role in assisting bone health is relatively new.

“Calcium, the most studied nutrient in the area of bone health, is known for its effectiveness in retarding bone loss in postmenopausal women,” they said. “Magnesium and vitamin D play important roles in calcium and bone metabolism. Vitamin K, originally recognised as a factor required for normal blood coagulation, is beginning to receive more attention for its role in bone metabolism.”

Due to the ecological nature of the study, a “causal linkage between the incidence of hip fracture and intake of vitamin K” could not be confirmed but the researchers said, “further research using more robust epidemiological methods is warranted.”

Estimates suggest that in the absence of primary prevention the number of hip fractures worldwide will increase to approximately 2.6 million by the year 2025, and 4.5 million by the year 2050.

Osteoporosis weakens bone strength which increases the likelihood of hip fracture, a problem that increases with age.