Why our daughters need their D level checked: It’s been know for decades that vitamin D deficiency weakens muscles. A study in the Dec, 2008. issue of Journal of Clinical Endocrinology & Metabolism reports its association with Cesarean delivery. Vitamin D levels were measured in 253 mothers. The rate of C-section was 14% for levels over 15 ng., and 28% for levels less than 15 ng. Normal is 32 to 100 ng). Many pregnant women would benefit if physicians ordered D levels for all their pregnant patients and treated to at least a level of 32 ng.

As for yourself - Vitamin D receptors are present in the brain. A recent study in the Journal of Geriatric Psychology and Neurology studied 2000 people over 65. Those with the lowest Vitamin D levels were more than twice as likely to have cognitive problems (an early sign of Alzheimers disease) than those with the highest. This shows that D deficiency may be an important not previously recognized link to Alzheimers.

And for infants- Autism is an epidemic that didn’t exist when we were born. It is a complex disease with various factors, as yet not fully understood, contributing to its origins. Studies have shown a higher incidence of autism in women who were pregnant during the winter when Vitamin D levels are lowest. Other studies have shown higher autism rates within the same state in counties that have more rainfall (and therefore less sunshine). Autism is higher in African Americans (who have levels 10 to 15 ng. lower because less sunlight is absorbed through darker skin). The New York Times in March, 2009, reported a surge of autism in Minneapolis among Somalian immigrants. Sweden is now reporting a rate of autism among Somalians at 3 times the rate of non-Somalians.. This is just some of the growing evidence that vitamin D deficiency is an important factor in autism. It will take decades to prove it, studies are only being talked about at this point, and the theory is relatively new. Some case reports have shown some improvements with correction of vitamin D insufficiency, but no large studies have been done. The tests done for an autistic child are quite extensive but routinely don’t include a 25-hydroxyvitamin D level. The Vitamin D Council is recommending that every such child should be tested; and any insufficiency should be treated by their physician. For this and many other reasons, 25-hydroxyvitamin D levels should be a routine pre-natal test. Any pregnant woman should be proactive and insist her obstetrician get the test.

The missing link- Why didn’t we hear of vitamin D deficiency 30 years ago? A March, 2009 study in Archives of Internal Medicine did a vitamin D level on about 15,000 blood samples that had been stored from both 1990 (average 30 ng.) and 2003 (average 24 ng.) The drop was 20%, and only 25% of 2003 levels were normal. Less sunlight exposure is felt to be the main explanation. This largely explains the increasing incidence of osteoporosis and other conditions associated with vitamin D deficiency.

Is Vitamin D a “secret?” Major publications have written about vitamin D in the past few years. In September,2006, Reader’s Digest published an article entitled:”The Miracle Vitamin: New evidence shows that getting enough D may be the most important thing you can do for you health.” In February, 2008, Parade Magazine listed vitamin D levels as one of “5 Medical Tests That May Keep You Well;” In the same month, Jane Brodie of the New York Times wrote “An Oldie Vies for Nutrient of the Decade.” Suggestions have even been made by prominent experts that the Surgeon General issue a report on Vitamin D because of the beneficial effect public awareness would have on decreasing health care costs and improving public health. I believe that the realization of the pandemic of vitamin D deficiency is the most important medical discovery in at least 40 years.

A guiding principle with taking Vitamin D

For those who like to keep things simple as more information becomes discovered about Vitamin D, the following should be remembered. If preventing osteoporosis was the ONLY thing that Vitamin D did,that would be enough reason to treat Vitamin D levels to at least 40 nanograms, and probably 50 nanograms.

Vitamin D and Cancer
One of Vitamin D's main actions is to prevent hyperproliferation of cells. That term describes what happens with cancer. There are substantial studies over the past several decades that show that low 25-hydroxyvitamin D levels vary inversely with the incidence of breast, prostate, and colon cancer. In a well publicized large study published in 2007, the lower the level, the more agressive the breast cancer. Prostate cancer studies have shown that vitamin D lowers the PSA level, an important tumor marker, and has effective anti-tumor action against prostate cancer.

Other cancers:
There are also many studies showing that vitamin D has activity in actually treating established cancer, especially breast and prostate cancer. Fewer studies have been done with less common cancers.

Thyroid cancer: There are in vitro and animal studies showing that thyroid cancer cells are significantly slowed down in their multiplication with Vitamin D. Thyroid nodules (which are a pre-cancerous lesion) are very common in hyperparathyroidism, and this condition is almost always associated with a low 25-hydroxyvitamin D level, which overstimulates the parathyroid glands.

Pancreatic cancer: Studies show that the incidence of pancreatic cancer is twice as common with low vitamin D levels.

Lung Cancer: Studies show a strong correlation of lung cancer with vitamin D levels, and substantial evidence that vitamin D has an chemotherapeutic effect when used in established cancer.

Vitamin D and the interaction of other risk factors
Many cancers have identified risk factors. Thyroid cancer is strongly associated with radiation to the neck as a child. Breast, prostate,and colon cancer have a number of proven risk factors. It has been well known and proven since 1965 that cigarette smoking causes lung cancer, and it is less well known that cigarette smoking is a strong risk factor of pancreatic cancer. A low vitamin D level works in conjunction with other risk factors. It is a non-specific stimulus to hyperproliferation of abnormal cells, and if these cells are damaged by other risk factors, it is a lot easier for cancer to develop. 25-hydroxyvitamin D levels, along with genetic factors, may be a large part of the explanation of why some smokers never get lung cancer. The same could be said of other cancers with their own risk factors.

What does this means in real terms? In an estimate so shocking it's hard for many to believe; according to leading Vitamin D experts and based on research studies that have been done, if every woman had a 25-hydroxyvitamin D level of 32 nanograms (the lowest level considered as normal, although it's far below the ideal level), the incidence of breast cancer would be cut 50%. The same probably can be said with men and women for colon, and men for prostate cancer. The same is also likely true for other cancers, but research has not been done yet.

Vitamin D and hereditary cancer genes - a theory
There are no studies that can be found regarding the BrCa1 gene, BrCa2 gene, and other heredity cancer symdromes and 25-hydroxyvitamin D levels. The BrCa1 gene has one of the most profound effects on it's carriers of all known hereditary cancer genes. Not all of it's female carriers get breast cancer, (it's frequently in the 30's when carriers that do get breast cancer become diagnosed, although just about all get ovarian cancer by the age of 58 if the ovaries aren't removed.) Would agressively treating 25-hydroxyvitamin D levels preferably to over 50 nanograms reduce the incidence of breast cancer in BrCa1 gene carriers? This is unknown, but could be an easy study to do, given the large amount of BrCa1 female carriers who follow the path of mammograms and MRIs of the breasts starting in their 30's. Unfortunately, I don't think this study is imminent. Carriers shouldn't wait; they should treat their vitamin D insufficiency to ideal levels.