Vitamin D and the Reduced Risk of Many Diseases
Vitamin D deficiency is associated with osteoporosis, bone fracture, muscle weakness, cancers (particularly breast and colon), autoimmune diseases, obesity, diabetes, schizophrenia, depression, asthma, lung dysfunction, influenza, kidney disease, and high blood pressure, and cardiovascular disease. During pregnancy and infancy vitamin D insufficiency is also associated with preeclampsia (pregnancy-induced hypertension), low birth weight, neonatal hypocalcemia (low blood calcium), poor postnatal growth, bone fragility, and increased incidence of autoimmune diseases and childhood asthma.
There is no debate in the medical community that there is a vitamin D deficiency epidemic that is causing a myriad of problems, and that people need to be supplementing with much higher doses than the traditionally-recommended dose of 400 IU per day. It’s clear that optimal supplementation should be at least 2000 IU/day, if not 4000 IU/day or higher.
Vitamin D Helps Prevent Osteoporosis
For years, the recommended dose of vitamin D (400 IU/day) was to help strengthen bones and reduce falls and hip fractures. However, there has been an explosion of research (both retrospective and prospective controlled studies), particularly over the last 5 years advancing our understanding that the worldwide vitamin D deficiency epidemic has an effect on much more than bone development and maintenance.
Vitamin D May Help Prevent Insulin Resistance
Adult-Onset Diabetes begins with insulin resistance. It is known that vitamin D deficiency is a common cause of insulin resistance. Although not all studies have been consistent, the studies that have shown a reduction in insulin resistance revealed the association at blood serum vitamin D concentrations ( 25-hydroxvitamin D, or 25-OH-D) in the range of 35 – 42 ng/ml. 1, 2, 3
Vitamin D is Associated with Decreased Risk of Breast and Colon Cancer
Blood serum levels of vitamin D (25-OH-D) above 40 ng/ml are associated with a decreased risk of breast and colon cancer. Vitamin D appears to enter breast cancer cells and trigger apoptosis (programmed cell death), much like many antioxidants.
Pooled data from observational studies showed that women whose serum 25-OH-D levels were at least 52 ng/ml had a 50% associated decreased incidence of breast cancer. Certainly, prospective controlled studies are needed to provide further information, but given the safety of vitamin D and encouraging studies thus far there appears to be no reason for anyone to wait on supplementing with optimal doses now. 4, 5, 6, 7
Vitamin D and Reduced Risk of Heart Disease
Although further studies are needed to determine the full extent of the protective nature of vitamin D against heart disease, it is apparent that vitamin D deficiency increases the risk of both ischemic and non-ischemic heart disease. Vitamin D may influence how heart muscle functions, helps control blood pressure, influences parathyroid hormone levels, and plays a role in reducing inflammation and calcification of blood vessels, thus reducing plaque formation.
When 25-hydroxy-vitamin D levels are below 15 ng/ml the risk for heart disease is particularly elevated. With 25-OH vitamin D levels above 30 ng/ml cardiac benefits may be substantial, and possibly even greater at the optimal serum range of 50 – 80 ng/ml. 8
Vitamin D and Reduced Risk of Influenza
Vitamin D reduces the incidence of respiratory infections. 9, 10 Children with the lowest levels of vitamin D are 11 times more likely to develop respiratory infections. 11 When 60,000 IU of vitamin D was given each week for six weeks to children susceptible to respiratory infections the children were completely free of all such infections over the following six months. 12
The influenza virus (the “flu”) causes damage and kills people by causing massive inflammation through uncontrolled over-production of pro-inflammatory cytokines. Vitamin D down-regulates the expression of pro-inflammatory cytokines (such as tumor necrosis factor-alpha). 13 This is the same destructive pro-inflammatory cytokine process that occurs as we age …leading to aging and chronic disease of all organs, vessels, joints, and neurons. 14 , 15
Much could be said about reducing the incidence and severity of influenza, let alone chronic disease, simply by down-regulating the excessive pro-inflammatory cytokine production with optimal supplementation of vitamin D, …in particular with other vitamins, minerals, and antioxidants. If this weren’t enough, vitamin D up-regulates the expression of anti-microbial peptides, (bits of proteins) in immune cells. Anti-microbial peptides damage influenza viruses, bacteria, and fungi (by damaging their outer lipid membranes), allowing the immune system to eliminate them from the body. 16
Vitamin D and Reduced Risk of Complications of Pregnancy
Vitamin D is essential and a key modulator of calcium metabolism in children and adults, to avoid rickets and osteomalcia, respectively. As the fetus grows during the third trimester calcium demands rapidly increase, and vitamin D requirements become crucial for proper skeletal growth and optimal maternal and fetal outcomes. As with the majority of the population, and despite prenatal vitamin supplementation, vitamin D deficiency is an epidemic among pregnant and lactating women. (As a result vitamin D deficiency is common, if not an epidemic, among breastfed infants as well.)
Adverse health outcomes such as preeclampsia, low birth weight, neonatal hypocalcemia, poor postnatal growth, bone fragility, and increased incidence of autoimmune diseases have been linked to low vitamin D levels during pregnancy and infancy. 17, 18
Minimum adequate blood levels of vitamin D (25-OH-D) during pregnancy should be greater or equal to 32 ng/ml (and possibly closer to 50 ng/ml). In order to achieve and maintain 25-hydroxvitamin D serum levels at 32 – 50 ng/ml, pregnant and lactating women need to supplement with at least 2000 to 4000 IU/day of vitamin D3 per day, which is both safe and effective.
Childhood Asthma Linked to Vitamin D Deficiency.
Vitamin D deficiency may partially explain the asthma epidemic. Recently, low serum vitamin D levels have been associated with higher risks for asthma exacerbations. Vitamin D plays a role in fetal lung growth and development. Epidemiologic studies have also suggested that higher prenatal vitamin D intakes have a protective role against wheezing illnesses in young children. Vitamin D may protect against wheezing illnesses through its multiple immune effects. In addition, vitamin D may play a therapeutic role in steroid resistant asthmatics. 19
Supplementing with vitamin D may help prevent asthma and the exacerbation of this disease, as well as help treat steroid resistance.
Measuring Your Vitamin D Status
The only true way to know your vitamin D status, and therefore your proper daily dose, is with a blood test, in which the metabolically-active form of vitamin D, 25-hydroxvitamin D (25-OH-D, or calcidiol) is measured. Relatively recently (over the past 5 to 7 years) when vitamin D’s role in the prevention of degenerative diseases beyond prevention of osteoporosis was recognized, the medical experts recommended a minimum target blood level of 30 ng/ml of 25-hydroxyvitamin D. (I emphasize that “minimum target level” means just that, “minimum!” It does not mean “optimal.”) Therefore, the reference lab ranges was raised to 32 – 100 ng/ml. Most experts in the field of researching and treating vitamin D deficiencies have recommended that “optimal” serum 25-OH-D levels begin at 42 ng/ml, with the ideal target range being achieved 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. To attain the optimal levels between 50 and 80 ng/ml that same person may need to supplement with 4000 IU per day or more.
On the other hand, a person who weighs 225 lbs. may require 10,000 IU/day to maintain 25-hydroxy vitamin D blood serum levels between 50 and 80 ng/ml. In all instances, the only way to accurately know the “true daily dosage” for a particular person would be to first estimate a starting vitamin D dose, get a serum 25-OH vitamin D test; adjust the dose accordingly, and get re-tested several weeks later.
Are High Doses of Vitamin D Safe?
What dose of vitamin D, or more accurately, what serum blood level, is required to prevent chronic disease and maintain optimal health AND not have toxic side effects? In other words, is long-term “high dose” vitamin D3 supplementation safe?
There is concern that high doses of vitamin D may elevate serum calcium levels and cause kidney stones in those at risk. To partially answer that question we can look at one study in which participants were administered extremely high doses of vitamin D. In a 12 week study, 69 vitamin D deficient patients received either a single oral, or a single intramuscular injection of 300,000 IU of vitamin D. During the 12 week study no cases of hypercalcemia (elevation of blood calcium) were observed. 20
There are no credible reports of vitamin D toxicity with chronic daily vitamin D3 supplementation up to 10,000 IU/day. 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. 21
Are there Contraindications for High-Dose Vitamin D?
Primary hyperparathyroidism is the main contraindication. Also, high dose vitamin D 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 Ratio and Balance
Vitamin D is one powerful, important, and safe nutrient in which we all should be taking. However, it should be taken with a full balance, and proper spectrum and ratio of vitamins, minerals, essential fatty acids and other antioxidants for optimal health. One example of proper ratios and understanding of supplementation is the fact that supplementing with vitamin A can neutralize the beneficial effects of vitamin D. 22
Most people are aware that high levels of vitamin A can cause birth defects and harm the liver. 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. 23, 24
preparations contain vitamin 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 important 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 4000 IU/day and having your blood tested to achieve the target range of 50 – 80 ng/ml.
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