Vitamin D has been in the health press spotlight recently as researchers link vitamin D deficiencies to a range of health problems. On the US-based Medline Plus website, numerous articles have been posted detailing research relating to Vitamin D which suggests that low levels of Vitamin D could not only put 40% of US infants and toddlers at risk of developing type 1 diabetes and dental problems, but also raise the death risk of people with heart disease, colon and breast cancer.
Vitamin D is also known as ‘the sunshine vitamin' because it is produced naturally when the body reacts to sunlight. The use of sunscreen and warnings to stay out of the sun due to skin cancer risks could be contributing to reducing levels of vitamin D in many people. Few foods naturally contain Vitamin D, which is essential for strong bones as it helps the body absorb calcium.
According to a study conducted by researchers from Children's Hospital in Boston, which appears in the June 2008 issue of the Archives of Pediatrics and Adolescent Medicine, at least 40% of American infants and toddlers aren't getting enough Vitamin D. Because human breast-milk lacks sufficient Vitamin D, the number of babies in the research sample being breast-fed was important to the findings.
"These data underscore the fact that breast-fed infants should be supplemented with vitamin D," said study author Dr. Catherine Gordon, director of the bone health programme at Children's Hospital. She added that mothers who are breast-feeding often need vitamin D supplements as well.
In addition to helping maintain bone health, Gordon said that vitamin D also appears to play a role in maintaining the immune system and that people with low vitamin D levels may be more susceptible to autoimmune diseases, such as type 1 diabetes, multiple sclerosis and certain cancers.
The link with type 1 diabetes has been supported by a new analysis of current research that provides ‘the strongest evidence to date' that giving small children supplemental vitamin D will help prevent them from developing type 1 diabetes later in life.
Co-authors Dr Christos S. Ziptis of Stockport National Health Service Foundation Trust and Dr A.K. Akobeng of Booth Hall Children's Hospital in Manchester U.K. have noted in their report in the Archives of Disease in Childhood that there are a number of clues suggesting a link between low vitamin D levels and type 1 diabetes.
The investigators reviewed all published research on vitamin D supplementation and diabetes risk and overall they found that infants who were supplemented with vitamin D were 29% less likely to develop type 1 diabetes than children who had not received supplements.
It has also been revealed in a study at the International Association for Dental Health in Toronto, Canada that by maintaining adequate vitamin D levels during pregnancy, mothers may be protecting their babies against early tooth decay in childhood.
Dr Robert Schroth from the University of Manitoba reported that mothers of children who developed cavities at an early age had significantly lower vitamin D levels during pregnancy that those whose children were cavity-free.
Another new study has found that women with breast cancer who have a vitamin D deficiency at the time of diagnosis are more likely to have a recurrence or to die from the disease. The researchers also found that only 24% of the patients had adequate levels of vitamin D when they were diagnosed.
Dr Nancy Davidson, director of the breast cancer programme at the John Hopkins Kimmel Cancer Centre and President of the American Society of Clinical Oncology said, "This study found that vitamin D deficiency is very common among women with breast cancer, and it suggests that vitamin D deficiency is linked to poorer outcomes in these women."
Although previous studies that indicated high levels of vitamin D may reduce the risk of getting colon cancer by 51% were disputed by others studies, a new study has now suggested that high blood levels of vitamin D could boost the survival odds of colon cancer patients by 48%.
"Vitamin D has been studied for many years, and there is a lot of data that could be implicated in cancer pathogenesis," explained lead researcher Dr Kimmie Ng. from the Dana-Farber Cancer Institute in Boston. "Vitamin D is involved in a lot of things that can go wrong in cancer," she noted.
According to Ng., the vitamin may improve survival in colon cancer patients by slowing the growth of tumour cells and may also be involved in killing cancer cells and inhibiting the growth of blood vessels in tumours.
While vitamin D deficiencies have been associated with falls, fractures, cancer, immune dysfunction, cardiovascular disease and high blood pressure, a new study now links insufficient vitamin D with the risk of dying, states a report published in the June 23, 2008 edition of the Archives of Internal Medicine. The researchers wrote ‘apart from the proved effects that vitamin D has on bone metabolism and neuromuscular function, appropriate serum levels are associated with a decrease in mortality.'
Although he was not involved in the study, Robert U. Simpson, a professor in the department of pharmacology at the University of Michigan School of Medicine states, "This is a very important study that shows low levels of vitamin and low vitamin D hormone levels are associated with cardiovascular mortality and mortality itself in a population of patients with coronary heart disease. This study supports the current interest in raising the minimum daily requirement for vitamin D and encouraging greater surveillance of vitamin D status in the general population and specifically heart disease patients."
There is still, however, a lot of confusion about the health benefits of vitamin D and daily allowance recommendations vary greatly around the world.
For the full stories on vitamin D refer to www.nlm.nih.gov/medlineplus/news.