It is well known that vitamin D deficiency is associated with osteoporosis, bone fracture, increased falls, muscle weakness, increased risk of certain cancers (particularly breast and colon, and possibly prostate), autoimmune diseases, obesity, insulin resistance and type 2 diabetes, schizophrenia, depression, asthma, lung dysfunction, influenza, kidney disease, high blood pressure, and cardiovascular disease. Even complications of pregnancy, preeclampsia (pregnancy-induced hypertension) and gestational diabetes, are associated with vitamin D deficiency. In infants, the vitamin's insufficiency has also been linked to low birth weight (caused by low levels from the mother during pregancy) neonatal hypocalcemia (low blood calcium), poor postnatal growth, bone fragility, and increased incidence of autoimmune diseases and childhood asthma.
Prevention of Osteoporosis
The standard recommended dose of 400 IU/day of vitamin D was in general to help maintain "good health," and to help reduce the risk of osteoporosis, falls, and hip fractures. Over the last 5 years, there has been an explosion of studies expanding our knowledge and indicating that higher doses have much more of an effect on overall health and on the prevention of various chronic diseases than just bone development and the prevention of osteoporosis. This was standard while I was practicing medicine to recommend calcium, magnesium, and vitamin D to women of menopausal age. However, I now recommend doses much higher than 400 IU/day.
Insulin Resistance
A common problem I saw in my medical practice, associated with aging and increased weight was insulin resistance, which often led to metabolic syndrome or full-blow Type 2 diabetes. To help reduce the risk of diabetes, metabolic syndrome, and insulin resistance I would encourage my patients to maintain a low-glycemic diet, exercise at least 4 times a week, and be on a broad spectrum nutritional supplementation program. Often this made the difference for people who took it seriously and made significant changes.
Insulin resistance begins with oxidation of insulin receptors. Anything that cause more oxidation, and therefore more inflammation, can lead to insulin resistance, and ultimatley Type 2 diabetes. Continued consumption of high-glycemic food (simple sugars and starches) will damage insulin receptors via inflammation/oxidation. With continued oxidation and inflammation of insulin receptors full-blown Type 2 diabetes develops. Lately, it has been discovered that vitamin D deficiency is a contributing cause to insulin resistance, giving further support to my recommending higher doses.
Although not all studies have been consistent and demonstrating a reversal of insulin resistance with vitamin D supplementation, the studies that have shown benefits in reversign insulin resistance have been the studies demonstrating blood serum 25-hydroxvitamin D (or 25-OH-D) concentrations that were at least in the range of 35 - 42 ng/ml. This may suggest that high doses may be needed to see a benefit in the prevention, and possible reversal of insulin resistance.
Decreased Risk of Breast and Colon Cancer Associated with Supplementation
As a former practicing board-certified Ob/Gyn, I had many patients who had a history of breast cancer, or a family history of breast cancer. Colon cancer was also a concern, as its incidence is second to breast cancer. A decreased risk of breast and colon cancer (and possibly prostate cancer) has been associated when blood serum levels of 25-hydroxvitamin D (25-OH-D) are 40 ng/ml or above. For most women, this would require a dailly dose near 4000 IU/day.
I had many patients using tamoxifen to treat or suppress the recurrence of breast cancer. However, tamoxifen has its own concerns (among them possible endometrial cancer). Interestingly, much like drugs that are used to treat breast cancer, such as tamoxifen, vitamin D enters breast cancer cells and triggers apoptosis; whicself-destruction, or "cellular death," of cancer cells. Actually, several various antioxidants; e.g., turmeric extract, polyphenolic compounds; such as grape seed extract, cruciferous extract, resveratrol, green tea extract, and olive extract) all cause apoptosis, or cellular self-destruction. The benefit of apoptosis compared to chemotherapy drugs and radiation therapy is that it causes cancer cell dealth without toxicity or destruction to normal cells.
Although the knowledge and use of antioxidants to kill cancer cells is as of yet limited, and thefore too early to be used to replace current toxic therapies for cancer, there is much promise for vitamins and other antioxidants in the near future. According to the research, I am a believer that antioxidants, and like substancs may help to prevent to the initiation of cancer, and therefore, along with a proper diet and lifestyle, everyone should be taking quaility supplements.
Specifc to this article, as I have searched to find out what dose of vitamin D women "should be" taking for preventative measures against breast, ovarian, and colon cancer, I have discovered that the studies have shown an association between women whose serum 25-OH-D levels of at least 52 ng/ml or higher and a 50% decreased incidence of breast cancer. Ovarian and colon cancers are similar in that there is a significant decreased incidence when 25-OH-D levels are above 50 ng/ml; and particular when they reach 80 ng/ml.
As I speak on the "Power of Nutritional Supplementation," both in lectures and on my audio CD, I suggest that among other nutrients, when one considers there are so many potential health benefits to be obtained from nutritional supplementation of specific vitamins, let alone a full-range of quality supplements, with virtually no toxic effects, I have to ask why would anyone wait to supplement?
Reduced Risk of Heart Disease Associated with Vitamin D
Vitamin D deficiency increases the risk of both ischemic and non-ischemic heart disease. Supplementation also helps control blood pressure, it influences parathyroid hormone levels, influences the function of heart muscle, and plays a role in reduction of inflammation and calcification of blood vessels, thus helping to reduce atherosclerosis.
The risk for heart disease is particularly high when 25-OH-D blood levels are below 15 ng/ml. With 25-OH-D levels above 30 ng/ml cardiac benefits may possibly be significant. Obviously, more studies are needed to draw conclusions about this vitamin's role in maintaining and/or reducing cardiovascular disease, but once again, I can only say that there is now enough evidence when taken as a whole, for everyone to consider supplementing with adequate doses of this all-important vitamin for any or "all" of the potential health benefits.
Reduced Risk of Influenza with Vitamin D
It is well established that vitamin D reduces the incidence of respiratory infections. Children who have been found to have the lowest 25-hydroxyvitamin D blood levels are 11 times more likely to develop respiratory infections. I have been asked about the safety and effectiveness of children supplementing with this vitamin. One can only look to clinical information. Children with recurrent respiratory infections have been given as high a dose as 60,000 IU of vitamin D3 (the active form) each week (for six weeks), and found to have not one such infection for the following 6 months!
Many people suffer and die from influenza, or the "flu." They don't die of the viral infection per se, as much as they die from the body's over-reaction. The influenza virus causes an uncontrolled over-production of inflammatory cytokines. Interestingly, vitamin D turns down this process by "down regulating" the expression of pro-inflammatory cytokines, such as tumor necrosis factor-alpha.
Actually, the pro-inflammatory cytokine process is the same inflammatory process that occurs in chronic disease, such as inflammation of arteries in atherosclerosis, inflammation in arthritis, damage to neurons, and inflammation and damage caused by cancer cells and by the aging process itself.
Think about the possibilities of reducing inflammation, by down regulating cytokines (tumor necrosis factor alpha, etc.) and thus reducing the incidence and progression of many chronic degenerative diseases, including heart disease, cancer, Alzheimer's disease, arthritis, diabetes, respiratory infections, liver and kidney disease, and the aging process itself!
Regarding vitamin D (really a hormone) and the protection of respiratory infections and influenza, in addition to the down regulation of inflammatory cytokines, this unique hormone also up-regulates the expression of anti-microbial peptides in immune cells. Anti-microbial peptides damage the outer lipid membranes of influenza viruses, bacteria, and fungi allowing the white blood cells (macrophages) from the immune system to eliminate them from the body.
I suggest that adults and children supplement with much higher doses than what was has been traditionally recommended to reduce the incidence of respiratory infections and help support the immune system, particularly during winter months when exposure to sunlight is decreased.
Vitmain D May Help Reduce the Risk of Complications of Pregnancy
Maintaining health during pregnancy is a chief concern of mine because it is critical that women get proper cellular nutrition throughout their pregnancies. Optimal supplementation should take place before a woman even knows she's pregnant. This is one reason why I recommend all women of child-bearing age be on a full-spectrum of quality nutritional supplements. Now, with recent information about the benefits of vitamin D during pregnancy, the amount of vitamin D in prenatal vitamins is quite inadequate,...at least in my opinion.
Vitamin D plays a key role for calcium metabolism during pregnancy and development in order to prevent infantile rickets and adult osteomalacia. During pregnancy, calcium demands rapidly increase, particularly in the third trimester. Because of this, vitamin D, which is required for calcium incorporation into the bones becomes crucial for proper skeletal growth and optimal maternal and fetal outcomes. Despite widespread use of prenatal vitamins containing what is thought to be "adequate" doses of vitamin D, there is still a vitamin D deficiency epidemic among pregnant and lactating women.
It is even more important that a pregnant woman have optimal vitamin D blood levels than a non-pregnant woman, as her baby's health depends on it,...not only during fetal life, but during the next two decades of that baby's life!
Low vitamin D levels during pregnancy and infancy are associated with maternal preeclampsia and pregnancy-induced hypertension, neonatal low birth weight and hypocalcemia, poor postnatal growth, bone fragility, and increased incidence of autoimmune diseases and asthma of the child.
During pregnancy a minimum blood level of vitamin D (25-hydroxyVitamin D) should be at least 32 ng/ml or greater; and optimally closer to 50 ng/ml. In order to achieve and maintain 25-hydroxvitamin D serum levels at 32 - 50 ng/ml, I suggest that pregnant and lactating women would possibly need to supplement with a dose between 2000 and 4000 IU/day of vitamin D3 per day, which is both safe and effective. Of course, this is beyond the level found in all prenatal vitamins.
Childhood Asthma Linked to Vitamin D Deficiency
The asthma epidemic may be explained in part by the vitamin D deficiency epidemic. There is a direct correlation between low serum vitamin D levels and higher risks for asthma exacerbations. Vitamin D plays a role in fetal lung growth and development. Epidemiologic evidence suggests that higher prenatal vitamin D intake has a protective role against wheezing illnesses in children. Vitamin D may protect against wheezing illnesses through its multiple immune effects as discussed above. In addition, vitamin D may play a therapeutic role among asthmatics from becoming steroid resistant.
Above I indicated that vitamin D plays an important role in reducing the risk of respiratory infections. In children, and adults for that matter, with asthma, supplementation with high dose vitamin D is of even more importance, as a respiratory infection can trigger attack.
Measuring Your Vitamin D Status
The question on most people's mind is, "How much vitamin D is the right dose?" The best way to know one's "correct" dose is to know your 25-hydroxyVitamin D blood level. This is the metabolically-active form of vitamin D, and is also known as calcidiol. It is abbreviated as 25-OH-D. In the past, "adequate" blood levels were set to prevent rickets and then osteoporosis. The myriad benefits and safety of vitamin D is coming to light.
Most laboratories have a normal reference range for 25-OH-D of 32 - 100 ng/ml. After studying what many of the experts in the field of vitamin D deficiency treatment have recommended, it varying widely, I am in line with suggesting that one's "optimal" serum 25-OH-D level should be between 50 - 80 ng/ml.
What Dose of Vitamin D is Optimal?
The vitamin D dose required to attain a serum level range of 50 - 80 ng/ml will vary from person to person, mostly based upon body mass (weight) and sun exposure. Although this will vary considerably, a 150 lb person who supplements with 2000 IU of vitamin D per day may attain blood level range of 25-OH-D between 30 and 45 ng/ml, depending upon sun exposure. In my experience, it seems that this same person may need to take 4000 IU/day, or more, to attain optimal blood levels between 50 and 80 ng/ml.
Again, from my experience, and it this will vary widely. A person who weighs 225 lbs. may require a dose of 10,000 IU/day to maintain 25-hydroxyVitamin D blood serum levels between 50 and 80 ng/ml. A person's true dose can only be determined by blood tests and titration (adjustments based upon the blood tests).
My suggestion would be to start with vitamin D at either 4000 to 6000 IU/day, depending upon your weight; or you may safely opt to take 10,000 IU/day, and then have your 25-OH-D blood level tested about 6 to 8 weeks later. Your optimal blood level target range for optimal health is 50 - 80 ng/ml. Therefore, once you know your blood level, you may adjust your daily vitamin D intake accordingly.
Are High Doses of Vitamin D Safe?
Is long-term "high dose" of vitamin D3 safe? There may be concern that high doses of vitamin D may elevate serum calcium levels and cause kidney stones in those at risk. There was a study in which vitamin D deficient patients received either a single oral, or a single intramuscular injection of 300,000 IU of vitamin D and followed for 12 weeks. During the 12 weeks not one person had elevated levels of serum calcium (or hypercalcemia).
This doesn't mean that chronic super high doses of vitamin D will not raise blood calcium levels; however, there are no credible reports of vitamin D toxicity with chronic daily vitamin D3 supplementation up to 10,000 IU/day, including elevation of blood calcium. In fact, many vitamin D expert clinicians are routinely recommending doses well above 10,000 IU/day. Hypercalcemia (an elevated serum calcium level) is only observed with synthetic vitamin D analogues, such as calcitriol.
Since it is safe for most people to supplement with vitamin D with doses as high as 10,000 IU/day (and possibly higher) without concern, my recommendation of a starting dose between 4000 - 6000 IU/day is quite conservative.
Are there Contraindications for High-Dose Vitamin D?
Primary hyperparathyroidism is the main contraindication. Also, high dose vitamin D3 supplementation may cause elevation of serum calcium levels in patients with sarcoidosis, tuberculosis, or lymphoma. Therefore, in such cases, patients dosing with levels above 2000 IU per day should do so only with caution AND under the care and direction of a physician.
One Last Word: Maintain Proper Ratios and Balance of Vitamins
Vitamin D3 is obviously safe. It has been underestimated as an important vitamin for many decades for maintaining optimal health at least, and possibly for reducing the risk of many chronic diseases if boosted to optimal blood levels. However, as will all vitamins, minerals, antioxidants, essential fatty acids, or any other nutrient, vitamin D should be taken in balance! All nutrients should be used to supplement a healthy diet, and used in conjunction with exercise and a healthy lifestyle.
Balance and proper ratios of nutrients are critical, as in the case of vitamin D with vitamin A. Vitamin A can neutralize the beneficial effects of vitamin D. In addition, many people are aware that high doses of vitamin A can be toxic to the liver and cause birth defects. However, most are not aware that vitamin A and vitamin D compete for each other's function in the body. Supplementing with excess amounts of vitamin A can suppress the important cancer-fighting effects of vitamin D.
Most multivitamin preparations contain vit A. Vitamin A (or pre-formed vitamin A) is different from pro-vitamin A, or beta-carotene. Beta-carotene does not interfere with vitamin D. Nor is beta-carotene associated with birth defects or liver problems.
Therefore, in choosing a quality, broad spectrum supplement brand, it is my suggestion to choose one that provides beta-carotene (a.k.a. "pro-vitamin A"), not vitamin A. This is just one of many criteria in choosing a quality supplement brand. As it relates to this article, choose a supplement that provides a daily dose of vitamin D3 of at least 2000 IU/day,...and consider taking at least 4000 IU/day and having your blood tested to achieve the target range of 50 - 80 ng/ml.
We should never rely on one vitamin, juice, or magic potion to cure all our problems. However, we should not ignore the ever-emerging evidence and promise that science is uncovering of the benefits nature has to offer in helping us to maintain optimal health.
I am a major proponent of using a broad spectrum of high quality vitamins, minerals, antioxidants, and essential fatty acids at proper doses and balance, along with healthy eating and proper lifestyle. I do not claim that all the answers are found in one vitamin or antioxidant, but many of the answers to optimal health are found in the synergistic action of the blend and balance of the fullest range of supplementation we are willing to incorporate into our lives.
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