Sunlight is not enough.
It’s that time of year when I endure my run of doctor visits, lab tests and diagnostic imaging, hoping that once again, NED will be my companion when they’re all done. I just picked up a copy of three pages of lab results, all good, and one of them prompted me to dash off a quick post.
Research into Vitamin D has been prolific in recent years, with results that have implications for many of us. Vitamin D helps us absorb calcium and other bone-building nutrients. Inadequate Vitamin D forces the body to steal calcium from bones and thus increases our risk of fractures and osteoporosis. The most readily available source of D is from sun exposure, but weather, geographic latitude and the risk of skin cancer all limit how much we can get from the sun. Some studies have confirmed the fact that many if not most of us in North America do not get enough D, because adequate sunshine is just not available. A cogent summary published by Harvard Health reports on these findings. Not only can we not get enough D from sun exposure, but the old minimum daily requirement of 400 IUs daily is inadequate. Most of us may need at least 1,000 IUs daily to keep our bones healthy.
More than just bone health.
Bone health is crucial for all of us, but it’s not the only reason we need adequate D. According to the Harvard piece, “it’s active in many tissues and cells besides bone and controls an enormous number of genes, including some associated with cancers, autoimmune disease, and infection. Hardly a month goes by without news about the risks of vitamin D deficiency or about a potential role for the vitamin in warding off diseases, including breast cancer, multiple sclerosis, and even schizophrenia.” Multiple studies, summarized in the International Journal of Health Studies, have reported an association between deficient D and a higher risk for developing “obesity, diabetes, hypertension, depression, fibromyalgia, chronic fatigue syndrome, osteoporosis and neuro-degenerative diseases including Alzheimer’s disease. Vitamin D deficiency may even contribute to the development of cancers, especially breast, prostate, and colon cancers.” Even in the Middle East, where inadequate sun ought not to be a factor, studies have found significant D deficiencies among men and women.
Several studies in particular have demonstrated an association between low D and increased risk of breast cancer, particularly in premenopausal women. It was the combination of reading these studies on breast cancer as they began to emerge a few years ago and my mother’s osteoporosis, causing severe spinal deformity that eventually contributed to her death, that prompted me to start taking 1,000 IUs of D3 a day. After six months of this self-imposed regimen, I asked my primary care doc to test my vitamin D level, accomplished by a simple blood test, and was astonished to find that my D was still below normal. I immediately increased it, and now take 20,000 IUs of D3 a week, in the form of readily available D3 gel capsules, which gives me about 2,800 IUs a day. It’s important to take D supplements in the right form. D3 is the one that is most readily absorbable. The good thing about D is that, because it is fat soluble and thus stored in the body, you have the option of taking it daily or weekly, as you prefer. I have been taking my weekly dose for about 3 years now.
After about 4 months of taking this much D, I noticed that my lifelong struggle with recurring depression abated. For the first time in many years, I no longer had to take an SSRI, and have not had to take one since. Amazing. And without taking calcium supplements, my next bone density scan showed a slight improvement in my bone density. Also amazing.
For women who take aromatase inhibitors, which notoriously can wreak havoc on bone density, having your blood Vitamin D levels checked is crucial. Your doctor should also check your blood calcium level. You need to have enough of both, and infrequently, D supplementation may cause a higher than normal level of calcium, and require you to adjust your supplement level. A normal blood level of D is somewhere between 30 and 100 ng/mL (nanograms per milliliter), and researchers have recommended aiming for a level between 40 and 60 ng/mL. A normal calcium level is between 8.9 and 10.3 mg/dL (milligrams per deciliter).
A review of research on D and breast cancer prevention was published recently in PlosOne.org. This review study found that D’s role in preventing breast cancer for postmenopausal women was inconclusive, but did find that better results were found when D was taken in higher doses and taken with calcium. It also suggests that studies currently underway may yield clearer results.
Research does, however, suggest that D supplementation can mitigate bone loss caused by aromatase inhibitors. And a recent review study reported that, among several different options, D supplements were the one option that did help decrease joint pain among women taking AI’s.
My own labs this year are instructive. I wondered if perhaps my 20K IUs of D3 a week would now be shown to be too much. But my recent lab results showed that my D was nicely in the middle of normal range, as was my calcium. So, I’ll stick to my current dosage.
Now, I just have to get that damn mammogram in a few weeks…