Vitamin Information Center

Unalaska has many great things to offer, but intense sunlight is not one of them. Although the lack of powerful sun may be good for reducing our skin cancer risk, it is not good for our vitamin D levels. The body uses sunlight to make vitamin D from molecules in the skin. Many who live at northern latitudes, especially in the winter, have inadequate vitamin D levels. A study in the British Medical Journal estimates at least 1 billion people worldwide are vitamin D deficient.

Most tissues in the body have receptors for this important vitamin. All of its many functions are still being discovered. The primary role of vitamin D is maintaining normal blood levels of calcium and phosphorous. Long term vitamin D deficiency leads to rickets in children and a softening of the bones in adults.

Currently there is much research being done to discover the additional effects of vitamin D in our bodies. A recent study published in the journal Dibetologia suggests that vitamin D may play a role in preventing type 1 diabetes in children. Vitamin D deficiency has been associated with increased risk of cardiovascular disease, according to a 2008 article in the journal Circulation.

A 2007 article in the New England Journal of Medicine states that people who live at higher latitudes who have vitamin D deficiency, or lack exposure to the sun, have an increased risk of many cancers. The same article suggests vitamin D may also provide protection from hypertension, psoriasis, several autoimmune diseases (including multiple sclerosis and rheumatoid arthritis) and reduce the incidence of fractured bones.

Make sure that you are getting enough vitamin D. It is difficult to get enough from the sun in the summer in Unalaska and impossible in the winter. Check out this Web site from the Norwegian Institute for Air Research to calculate how much vitamin D you are getting from the sun based on your location, weather, skin color, and clothing: http://nadir.nilu.no/~olaeng/fastrt/VitD_quartMED.html.

Obtaining adequate levels of vitamin D from your diet is not easy either. Good dietary sources include fortified milk, eggs, and fatty fish. Some studies, such as one published in the European Journal of Clinical Nutrition last year, have shown that the vitamin D fortification of milk products is not adequate to prevent vitamin D deficiency.

Infants who are breast fed are at particular risk vitamin D deficiency according to a 2004 study published in the American Journal of Clinical Nutrition. Human milk contains little vitamin D, and women who are vitamin D deficient provide even less to their breast-fed infants.

There are differing opinions on the recommended daily intake, especially in light of new studies coming out every day. The USDA recommended daily intake is 400 IUs for a healthy adult. Some physicians recommend much more than that, particularly for those deficient in the vitamin. Because vitamin D can be stored in our bodies, there are high dosages available that can be taken only once a week or once a month.

A 2003 study published in the Journal of Pediatrics looked at the vitamin D levels of women and infants in Alaska. Based on this study, the American Academy of Pediatrics recommends a universal supplement for all infants not receiving vitamin D fortified milk. Talk to your health care provider about getting the right amount of vitamin D for your health.

Tiffany Kelly is medical student from the University of Washington who visited Unalaska for the month of July, 2008. She now lives in Anchorage.

Newswise — Long known for its role in preventing anemia in expectant mothers and spinal birth defects in newborns, the B vitamin folate, found in leafy green vegetables, beans and nuts has now been shown to blunt the damaging effects of heart attack when given in short-term, high doses to test animals.

In a new study, an international team of heart experts at Johns Hopkins and elsewhere report that rats fed 10 milligrams daily of folate, also known as folic acid or vitamin B9, for a week prior to heart attack had smaller infarcts than rats who took no supplements. On average, researchers say, the amount of muscle tissue exposed to damage and scarred by the arterial blockage was shrunk to less than a tenth.

The team’s findings, set for publication in the April 8 edition of the journal Circulation, come just weeks after other international studies in humans suggested that low-dose folic acid supplements may prevent dementia in the elderly and premature births.

“We want to emphasize that it is premature for people to begin taking high doses of folic acid,” says senior study investigator David Kass, M.D., a professor at The Johns Hopkins University School of Medicine and its Heart Institute.

“But if human studies prove equally effective, then high-dose folate could be given to high-risk groups to guard against possible heart attack or to people while they are having one,” says Kass.

The more likely and most practical advantage to ingesting supplements, he says, lies in folic acid’s potential to act as a short-term buffer for people who may be having a heart attack and who rush to their local emergency room complaining of chest pain.

Clinical trials are expected in the near future, although Kass says a major challenge in testing is that a high dose of folic acid for humans comparable to that given the rats would require an average-size adult to swallow more than 200 one-milligram pills per day, “an impractical and unrealistic regimen, even if the body excretes the excess.”

In addition, he cautions, “we do not yet know if folate is safe to consume in this high a dose, or how much or how little of it is needed to be effective,” citing 25 milligrams per day as the highest dose previously tested safe to consume in adults as.

Kass says that such large amount of folate may also yield unpredictable side effects. Some studies have linked the nutrient supplement to increased rates of colon and prostate cancer.

Each year, an estimated 565,000 first-time heart attacks occur in the United States, with an additional 300,000 recurrent heart attacks.

Results from the new study, conducted in rats - dozens were fed supplements and dozens more did not receive any - showed that overall pumping function during heart attack remained strong in vitamin B9-fortified animals.

The amount of blood pumped by the treated hearts during a 30-minute window when blood flow to the heart was restricted to simulate a heart attack stayed near normal for rodents, at an average ejection fraction of 73 percent. Meanwhile, it fell in the untreated group to 27 percent.

Similarly, the muscle wall at the front of the heart kept contracting during heartbeats, thickening by 37 percent in the supplement-fed group, but the muscle could barely compress, thickening by 5 percent, in the untreated group. (Sixty percent would be the normal amount of thickening in a healthy rat heart.)

Moreover, researchers found that an injection of folic acid into the bloodstream of rats that had never before taken supplements, within the first 10 minutes of a heart attack, was almost equally as effective as preventive therapy in reversing muscle damage, and in lowering infarct size by a factor of 10.

“Folic acid is already well known to be safe to consume in high doses in the short term, and it is very inexpensive, costing pennies per milligram, so its prospects look promising,” says Kass.

Researchers plan further tests to determine precisely why folate protects the heart, and to determine how effective it is in not-as-high doses. But they point out that it has long been known for its role in the normal workings of the cell’s principal energy source, the mitochondria, whose function is essential to maintaining healthy blood vessels.

It was this evidence that led to the latest study, which, says lead investigator An Moens, M.D., suggests that folate acts as an energy reserve in the heart, “providing much needed energy for muscle contraction, in the form of ATP, at the same time the heart is being starved for oxygen-carrying blood by a blocked artery.”

According to Moens, a postdoctoral cardiology research fellow at Johns Hopkins, study results showed that high-energy phosphate levels went down 43 percent in the blood of treated rats, but levels dropped by one-third more (by 66 percent) in untreated rats.

“With more fuel, the heart kept pumping even though its blood flow was reduced,” says Moens, now a cardiologist at the University of Antwerp in Belgium. “The smaller heart attacks seemed related to this better energy balance in the heart produced by the folate.”

In the study, heart function was monitored by more than two dozen key tests, such as echocardiogram and magnetic resonance imaging, as well as by blood analysis before, during and after the heart attack, when blood flow was allowed to resume in the coronary artery that had been blocked.

Among the team’s other findings that backed up the protective effects of folate on the heart were mild, slight dips in systolic blood pressure during heart attack in treated rats, while pressure fell in untreated animals by 25 percent. Similarly, blood flow was stable in the treated group, but dropped by 40 percent in untreated animals. Post-heart attack buildup of dangerous chemicals, known as reactive oxygen species, was halved in treated rats. And fatal arrhythmias, unstable heartbeats that can immediately follow a heart attack, also went down from 36.7 percent to 8.3 percent in the supplement-fed group.

“In future, we might just pop in an I.V., and give people high-dose folate while they are waiting for their catheterization or CT scans to search for blockages,” says Moens.

Funding for the study of folate, one of eight B vitamins, was provided by the National Institutes of Health and the Peter Belfer Laboratory Foundation, with additional support from the American Heart Association, the Belgian American Educational Foundations, as well as the University of Antwerp, Belgium.

In addition to Kass and Moens, other Hopkins researchers involved in this study were Hunter Champion, M.D., Ph.D.; Azeb Haile, M.S.; Muz Zviman, Ph.D.; Djahida Bedja, M.S.; Kathy Gabrielson, D.V.M., Ph.D.; Nazareno Paolocci, M.D., Ph.D. Kass is also the Abraham and Virginia Weiss Professor of Cardiology at Hopkins. Additional researchers from Belgium included Marc Claeys, M.D., Ph.D.; Dirk Borgonjon, M.S.; Luc Van Nassauw, Ph.D.; Floris Wuyts, Ph.D.; Rebecca Elsaesser, Ph.D.; Paul Cos, Ph.D.; Jean-Pierre Timmermans, Ph.D.; and Christiaan Vrints, M.D., Ph.D., from the University of Antwerp; and Barbara Tavazzi, M.D., Ph.D., and Guiseppe Lazzarino, M.D., Ph.D., from the University of Rome. Further assistance with biochemical analysis was provided by Pawel Kaminski, M.D., Ph.D., and Michael Wollin, M.D., Ph.D., both from the New York University School of Medicine.

BALTIMORE, March 27 (UPI) — Folate — vitamin B 9 – potentially may be used to limit the damage of a heart attack, U.S. researchers say.The study, scheduled to be published in the April 8 edition of the journal Circulation, finds the vitamin blunted the damage from heart attack in animal studies.

“We want to emphasize that it is premature for people to begin taking high doses of folic acid,” senior study investigator Dr. David Kass, of The Johns Hopkins University School of Medicine in Baltimore says in a statement. “But if human studies prove equally effective, then high-dose folate could be given to high-risk groups to guard against possible heart attack or to people while they are having one.”

“We do not know how much or how little of it is needed to be effective,” Kass cautions. A large amount could yield unpredictable side effects and studies have linked folic acid supplements to increased rates of colon and prostate cancer, Kass says.

Folate — naturally found in leafy green vegetables, beans and nuts — is sometimes used as a general term to include folic acid — the form of vitamin B9 put in supplements and added to foods, especially grain products.