Vitamin D Articles
Vitamin D Helps You Live Longer
High Blood Pressure Linked to Low Levels of Vitamin D
Vitamin D May Help Fight TB
Clear Link Shows Vitamin D Lowers Cancer Risk
People With Undetermined Pain
Tend to Be Vitamin D Deficient
MS threat may drop by taking
vitamin D
Vitamin D cuts colon cancer risk
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Vitamin D Helps You Live Longer
The importance of vitamin D in slowing down the aging process is confirmed in a new study.
In the American Journal of Clinical Nutrition, this new research shows scientists studied 2,160 women, aged 18 to 79 years old and measured leukocyte telomere length (LTL). LTL is a predictor of aging-related disease and decreases with each cell cycle and increased inflammation, the scientists said.
In more than 2,000 women, those who had higher levels of the vitamin in their body had longer telomeres. Telomeres are the part of the chromosome which shortens with age.
The scientists measured concentrations of 25-hydroxyvitamin D (the 'storage' form of vitamin D) and found a link between increased concentrations and telomere length.
They found that after taking into account the age of the volunteer, women with higher levels of vitamin D were more likely to have longer telomeres.
"The difference in LTL between the highest and lowest tertiles of vitamin D was 107 base pairs, which is equivalent to five years of telomeric ageing. This difference was further accentuated by increased concentrations of C-reactive protein, which is a measure of systemic inflammation," they stated.
To summarize; higher vitamin D concentrations, which are "easily modifiable through nutritional supplementation", are associated with longer LTL, which underscores the potentially beneficial effects of vitamin D on aging and age-related diseases.
Dr Brent Richards, the head researcher said: "These results demonstrate for the first time that people who have higher levels of vitamin D may age more slowly than people with lower levels of vitamin D.
"This could help explain how vitamin D has a protective effect on many aging related diseases, such as heart disease and cancer. Further research is needed to confirm these findings."
Another finding was that 700 women, who were already taking vitamin D supplements, had longer telomeres than those who weren't taking the supplements. There were no conclusions, however, as to the level of vitamin D needed to obtain these results.
Many are calling for an increase in vitamin D supplementation and presently, the recommended daily intake is set at 400 IU, and the tolerable upper intake level (UL) in Europe and the US is set at 2000 International Units (IU), equivalent to 50 micrograms per day. Research, particularly from clinical trials, suggests that this should be raised.
The Council for Responsible Nutrition (CRN), which is a US trade organization, concluded that the UL could be raised to 10,000 IU (250 micrograms per day).
The American Journal of Clinical Nutrition, November 2007
"Higher serum vitamin D concentrations are associated with longer leukocyte telomere length in women."
Brent Richards, Ana Valdes, Jeffrey Gardner, Dimitri Paximadas, Masayuki Kimura, Ayrun Nessa, Xiaobin Lu, Gabriela Surdulescu, Rami Swaminathan, Tim Spector and Abraham Aviv.
www.nutraingredients.com, 9/11/2007
High Blood Pressure Linked to Low Levels of Vitamin D
A new study reports that people with low levels of vitamin D may be at risk for high blood pressure - and the solution may easily be supplements.
There are an estimated 10 million people in the UK with hypertension, which is defined as having blood pressure higher than 140/90 mm Hg. Those people with this condition have a greater chance for developing cardiovascular disease. (CVD) In the EU, 50% of deaths are caused by CVD which is reported to cost the EU economy an estimated €169bn ($202bn) per year.
The main author of this study, Robert Scragg, wrote in the American Journal of Hypertension, "This finding may have public health significance, as vitamin D levels can easily, and cheaply, be increased by a modest increase in sun exposure or vitamin D supplementation,".
"However, first it needs to be confirmed by large, well-designed intervention studies," he cautioned.
Researchers, from the University of Auckland, University of Michigan, Hunter New England Area Health Service (Australia), compiled data from Third US National Health and Nutrition Examination Survey (NHANES III). The analysis did not include those on hypertensive medication. In all, 12,644 people (aged 20 or over, 6547 women) were reviewed.
Vitamin D ranking was measured using blood levels of 25- hydroxyvitamin D (25(OH)D).
Vitamin D refers to two biologically inactive precursors - D3, also known as cholecalciferol, and D2, also known as ergocalciferol. D3, produced in the skin on exposure to UVB radiation (290 to 320 nm), is said to be more bioactive. D2 is derived from plants and only enters the body via the diet, from consumption of foods such as oily fish, egg yolk and liver.
Both D3 and D2 precursors are hydroxylated in the liver and kidneys to form 25- hydroxyvitamin D (25(OH)D), the non-active 'storage' form, and 1,25-dihydroxyvitamin D (1,25(OH)2D), the biologically active form that is tightly controlled by the body.
Findings in the report state that non-Hispanic whites had the highest blood levels, followed by Mexican Americans, while non-Hispanic blacks had the lowest vitamin D levels.
The researchers stated, "Age- and gender-adjusted mean blood pressures were higher in non-Hispanic blacks than in Mexican Americans and non-Hispanic whites, consistent with results from the first phase (1988 to 1991) of NHANES III," .
"The finding that ethnic differences in vitamin D status explained about half of the increased prevalence of hypertension in non-Hispanic blacks, compared with non-Hispanic whites, supports the previous suggestion that low vitamin D levels in non-Hispanic blacks may be a factor in their increased hypertension prevalence," they added.
The subjects were then split up into five groups depending on blood levels, and the researchers calculated that people with the highest average 25(OH)D levels (at least 85.7 nmol/L) had systolic diastolic and blood pressure 3.0 and 1.6 mm Hg lower, respectively, than people with the lowest levels (40.4 nmol/L or less).
After adjusting the results to account for BMI, the associations remained statistically significant for systolic blood pressure.
"These results from a nationally representative US sample show that systolic BP and pulse pressure are inversely associated with serum 25OHD... The inverse association between serum 25OHD and systolic BP has clinical significance, because the latter variable is a better predictor of coronary heart disease risk than diastolic BP, particularly in older people," stated the researchers.
Vitamin D levels have been under scrutiny for quite some time with a growing number of authorities and researchers asking for increased levels.
Fifteen vitamin D experts from around the world called for international agencies to "reassess as a matter of high priority" dietary recommendations for vitamin D because current advice is outdated and puts the public at risk of deficiency.
A recent review of the science reported that the tolerable upper intake level for oral vitamin D3 should be increased five-fold, from the current tolerable upper intake level (UL) in Europe and the US of 2000 International Units (IU), equivalent to 50 micrograms per day, to 10,000 IU (250 micrograms per day).Source: American Journal of Hypertension (Elsevier)
July 2007, Volume 20, Issue 7, Pages 713-719
"Serum 25-hydroxyvitamin D, Ethnicity, and Blood Pressure in the Third National Health and Nutrition Examination Survey "
Authors: R. Scragg, M. Sowers and C. Bell
The American Journal of Clinical Nutrition, Vol. 85, pp. 860-868.
www.nutraingredients.com 7/25/2007
Vitamin D May Help Fight TB
With the recent news of a TB scare on a commercial airliner, a British study demonstrates how vitamin D may significantly boost a person's immunity to the disease.
Research at Newham University Hospital and Northwick Park Hospital (London) studied patients who had been exposed to TB and found that more than 90% had a vitamin D deficiency. The researchers then gave either a placebo or 2.5 mg of vitamin D to 192 volunteers and tested their blood to see how their immune systems fought off mycobacteria.
The study coordinator, Adrian Martineau, who is affiliated with Imperial College's (London) division of medicine, stated, "We found that a single large dose of vitamin D was sufficient to enhance a person's immunity to the bacteria. This is very significant, given the high levels of vitamin D deficiency in people at the highest risk of TB infection, and shows a simple, cheap, supplement could make a significant impact on the health of people most at risk of the disease".
Source: AR Martineau et al., "A single Dose of Vitamin D Enhances Immunity to Mycobacteria," American Journal of Respiratory and Clinical Care Medicine. April 26, 2007
Nutritional Outlook, June 2007
Clear Link Shows Vitamin D Lowers Cancer Risk
Greater intake of vitamin D is strongly recommended after studies showed evidence between increased vitamin D and lower cancer rates.
Dr. Cedric Garland, head of a research team from the University of California at San Diego Moores Cancer Center, suggests people consume more vitamin D through diet or supplementation.
Garland's research team reviewed 63 studies, including several large long-term ones, on the relationship between vitamin D and certain types of cancer worldwide between 1966 and 2004.
He said the benefit of vitamin D was as clear as the harmful link between smoking and lung cancer.
Dr. Garland is urging governments and public health officials to do more to get food manufacturers to fortify foods with vitamin D. He states, "There's nothing that has this ability to prevent cancer,"
His studies published in the American Journal of Public Health show a clear link with colon, breast and ovarian cancer. The paper concluded that vitamin D deficiency may account for several thousand premature deaths from colon, breast, ovarian and other cancers annually.
Dr. Garland suggests vitamin D could be especially important for people living in northern areas, which receive less vitamin D from sunshine. African Americans, who don't produce as much of the vitamin because of their skin pigment, could also benefit significantly from a higher intake.
Vitamin D is found in milk, as well as in some fortified orange juice, yogurt and cheeses, usually at around 100 international units (IU) a serving.
People might want to consider a vitamin supplement to raise their intake to 1000 IUs per day, Garland said, adding that it was well within the safety guidelines established by the National Academy of Sciences.
Another paper published in The Lancet this month (vol. 367, No.. 9504, pp 36-43) found that Vitamin D supplementation of pregnant women, especially during winter months, could lead to healthier bones in their offspring.
A team of researchers at the University of Southampton in the UK, is the latest in a series of reports showing the role of this vitamin in protecting bones. Vitamin D has been known to promote calcium and phosphorous absorption from food. It is essential in tooth and bone formation and now the new research shows the importance of bone health from the very start of life.
When the body is exposed to sunshine, vitamin D is produced. Vitamin D can also be consumed when eating milk, fish, liver or egg yolk. Some estimates, however, claim that as much as 60% of the population is vitamin D deficient because of poor diet or lack of sunshine.
American Journal of Public Health
Lancet, January 2006 (vol. 367, No. 9504, pp 36-43)
People With Undetermined Pain Tend to Be Vitamin D Deficient
People with persistent, nonspecific musculoskeletal pain should be regularly screened for
vitamin D deficiency, reports a study in a recent issue of Mayo Clinic Proceedings. Research conducted at the University of Minnesota found that 93% of all subjects with nonspecific musculoskeletal pain were vitamin D deficient.
A study of 150 children and adults at the University of Minnesota found that 100% of African American, East African, Hispanic, and Native American subjects were vitamin D deficient. In addition, all study patients under the age of 30 were vitamin D deficient. Of these, 55% were severely deficient. Five patients unexpectedly had no vitamin D at all.
"These findings are remarkably different than what is taught in medical school. We would expect vitamin D deficiency in older persons or housebound persons," says Greg Plotnikoff, MD, MTS, professor at the University of Minnesota's Center for Spirituality and Healing and lead researcher on the study. "We found the worst vitamin D deficiency in young persons-especially women of childbearing age. We were stunned to find no vitamin D at all in five patients who had been told that their pain was 'all in their head.' This study supports more routine testing for vitamin D deficiency.
"This pain is the most common type of complaint seen by primary care doctors. Patients with this type of pain should be tested for vitamin D deficiency," says Plotnikoff.
Vitamin D deficiency is associated with significant risks for osteoporosis, hypertension, diabetes, cancer, and autoimmune diseases such as multiple sclerosis. It is also harmful for developing fetuses and causes rickets in children.
According to the November 12, 2003, edition of the pain management issue of The Journal of the American Medical Association, unsuccessfully treated pain costs $61.2 billion per year.
An unrelated study in the December 2003 issue of Psychosomatics found that 37% of physician visits are for symptoms of no known cause, most frequently unexplained back, head, arm, and leg pain. A trial to assess management of persistent, nonspecific pain by prescription of vitamin D replenishment is recommended by Plotnikoff.
University of Minnesota, Minnesota, US
MS threat may drop by taking vitamin D
Women's risk cut by 40%
A huge study testing a long-held theory about the cause of multiple sclerosis has found that women who took a vitamin D supplement cut their risk of developing the incurable neurological disorder 40 percent. The study, which involved 187,563 women, is the first large, prospective examination of an observation that has been around for decades: MS may be caused, in part, by a lack of sunlight sufficient to allow the body to make its own vitamin D.
"What we found is it (vitamin D) is protective against MS," said Kassandra Munger, the study's lead author and a researcher in the department of nutrition at the Harvard School of Public Health. "How long that protection lasts, I'm not sure."
The study, published in this month's issue of Neurology, is part of the ongoing Nurses' Health Study. The women in this study were followed for 10 to 20 years. Those who took a daily multiple-vitamin supplement with at least 400 international units of vitamin D had 40 percent less incidence of MS than those who did not take a supplement with vitamin D. Depending on a person's age, 200 to 600 international units a day is recommended. Supplemental vitamin D can be toxic, and doctors cautioned against taking more than the recommended daily amount.
In the United States, as many as 350,000 people have the disease. Vitamin D from food sources did not seem to lower the incidence of MS.
Milwaukee Journal Sentinel, Jan. 13, 2004
Vitamin D cuts colon cancer risk
A diet rich in vitamin D appears to protect people from developing potentially cancerous growths in the colon, a study of more than 3,100 veterans found.
Patients who consumed the amount of vitamin D contained in daily servings of milk and fish were 40 percent less likely to develop polyps than those who got little or no vitamin D.
The study also confirmed previous research that found that cereal fiber and regular use of pain relievers such as aspirin and ibuprofen reduce the risk of advanced polyps and that smoking, heavy drinking and a family history of polyps raise the risk.
Diets high in calcium have been linked with a reduced colon cancer risk, and vitamin D is needed to help the body absorb calcium. But evidence about any protective effect from vitamin D alone is sparse, said Dr. David Lieberman, the lead author and a gastroenterologist at the Portland, Ore., Veterans Affairs Medical Center.
The study appears in Wednesday's Journal of the American Medical Association. (December 10, 2003)
It involved mostly men ages 50 to 75 who underwent routine colon cancer screening exams called colonoscopies between 1994 and 1997. The exams, in which a long flexible tube is snaked through the rectum into the entire large intestine, can detect and remove abnormal growths.
The American Cancer Society recommends the tests every 10 years starting at age 50 to help detect colorectal cancer, which is diagnosed in about 147,000 Americans each year.
Study participants filled out detailed health questionnaires before their exams asking about diet, family medical history and lifestyle habits. Participants were not asked about exposure to sunlight, which interacts with chemicals in the skin to produce vitamin D and is a major source of the vitamin.
Advanced polyps were found in 299 participants and colon cancer was detected in 30 participants.
Participants who reported consuming more than 645 international units of vitamin D daily were 40 percent less likely to have advanced polyps than those who consumed little or none of the vitamin. Experts generally recommend about 200 to 800 IUs of vitamin D a day for adults.
Food sources of vitamin D include some types of fish and fortified milk. For example, one tablespoon of cod liver oil has 1,360 IUs; 31/2 ounces of salmon have 360 IUs; and a cup of fortified milk contains 100 IUs.
Supplements are frequently combined with calcium and often contain at least 200 IUs, Lieberman said.
Dr. David Beck, chairman of colorectal surgery at the Ochsner Clinic Foundation in New Orleans, said the link between vitamin D and reduced risk of polyps is not surprising. Beck, however, questioned how accurately the researchers were able to assess people's vitamin intake since they relied on questionnaires rather than giving participants vitamin D-rich foods or supplements. Chicago, Illinois (AP) December 9, 2003
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