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Vitamin D Supplements
Type 2 Diabetes and Vitamin D -- (4/1/2018) Maintaining an adequate level of vitamin D is associated with a lower risk of type 2 diabetes. But does giving vitamin D to people with existing type 2 diabetes help them with glucose control? Find out what research is showing in the What It Does section of the Vitamin D Supplements Review. (Also see our Top Picks among vitamin D supplements.)
High-Dose Vitamin D & Cholesterol -- (3/17/2018) Giving high-dose vitamin D to people who are not deficient in it may backfire and increase cholesterol levels, as seen in a recent study. Get the details in the Concerns and Cautions section of the Vitamin D Supplements Review. (Also see our Top Picks among products).
Link Between Vitamin D and Multiple Sclerosis? -- (1/16/2018) Although some studies suggest vitamin D deficiency is a risk factor for developing multiple sclerosis, a recent review found vitamin D intake was not associated with a reduced risk. Learn more in the "What It Does" section of the Vitamin D Supplements Review >>
Vitamin D's Cardiovascular Effect -- (1/6/2018) Taking vitamin D can improve aspects of cardiovascular function in certain situations, as shown in a recently published study. Get the details in the "Cardiovascular disease, blood pressure, and cholesterol" section of the Vitamin D Supplements Review. (Also see our Top Picks among vitamin D supplements.)
Autism Risk With Low Vitamin D -- (12/2/2017) Babies born with very low blood levels of vitamin D are more likely to be autistic, according to a new study. This is consistent with a study published last year showing a higher rate of autistic children in mothers with very low vitamin D blood levels during pregnancy. Get the details in the "What It Does" section of the Vitamin D Supplements Review >> (Also see our Top Picks among vitamin D supplements.)
Vitamin D and Cardiovascular Disease -- (11/21/2017) Can high doses of vitamin D improve cardiovascular function? A large, one-year study in England recently sought to answer this question. Learn what the researchers discovered in the "What It Does" section of the Vitamin D Supplements Review (which includes our Top Picks for vitamin D supplements).
Vitamin D for Asthma -- (10/24/2017) Taking vitamin D can reduce the number of asthma exacerbations that require corticosteroid treatment, according to a recent study. Get the details in the "What It Does" section of the Vitamin D Supplements Review >> [Also see our Top Picks among vitamin D supplements in the Review.]
Vitamin D Toxicity -- (10/24/2017) Getting too much vitamin D is associated with negative effects. With continued use of enormous doses of vitamin D, toxic effects can occur, as has been reported with the use of a protein supplement containing vitamin D. See the details in the "Concerns and Cautions" section of the Vitamin D Supplements Review >>
Fatty Liver and Vitamin D -- (10/14/2017) A recent study showed that it is difficult to raise vitamin D levels in some people who have non-alcoholic fatty liver disease -- a condition affecting 30% of Americans. This is concerning, as there may be benefits to raising low levels of vitamin D in such people. Learn more in the "What It Does" section of the Vitamin D Supplements Review >>
Vitamin D2 or D3? -- (7/9/2017) Although both the D2 and D3 forms of vitamin D can raise blood levels of vitamin D, a new study showed one to be significantly better than the other — and there are some interesting explanations for this. Learn more in the "What to Consider When Using" section of the Vitamin D Supplements Review, which includes our Top Picks.
Vitamin D & Alzheimer's Disease -- (6/10/2017) Older people with insufficient levels of vitamin D had nearly triple the risk of developing Alzheimer’s disease that those with sufficient levels, according to a recent study. Those with the lowest levels also experienced a faster rate of cognitive decline. Get the details and information about optimal vitamin D levels in the "What It Does" section of the Vitamin D Supplements Review, which includes our Top Picks among supplements.
Early Menopause & Vitamin D -- (5/11/2017) Women who get more vitamin D from their diets have a lower risk of early menopause, according to a recent study. However, supplements don't seem to help. Get the details in the "What It Does" section of the Vitamin D Supplements Review >>
Vitamin D for Muscle and Balance? -- (4/28/2017) Why did a recent study show that both high and low-dose vitamin D didn’t improve muscle strength or balance in women despite the fact that other studies have shown vitamin D to help? The likely answer has to do with the vitamin D status (i.e., blood levels) of the people chosen to participate in these studies. To find out what you should do to improve your balance and reduce your chance of falling, see the "Muscle, Balance and Falls" section of the Vitamin D Supplements Review >>
Don't Bother with High-Dose Vitamin D -- (4/5/2017) Taking a moderate dose of vitamin D (particularly if you are deficient) can be very helpful, but a growing number of studies show a lack of benefit (and some adverse effects) with high-dose vitamin D. The latest study, released this morning, focused on cardiovascular disease. For details, see the "Cardiovascular disease" section of the Vitamin D Supplements Review >>
Vitamin D and Cancer -- (4/1/2017) Although studies have shown that sufficient vitamin D in the blood is associated with lower risk of developing and dying from cancer, a new study among women found no cancer benefit from taking vitamin D supplements. However, the study had a major weakness. For details, see the "What It Does -- Cancer" section of the Vitamin D Supplements Review >>
Right Dose of Vitamin D to Reduce Falls -- (3/25/2017) As we've reported in the past, vitamin D can reduce falls in older people, but too much can increase falls. A new study helps nail down the ideal dose and blood level to reduce falls. For details, see the "What It Does" section of the Vitamin D Supplements Review >>
Can High-Dose Vitamin D Backfire? -- (3/11/2017) A recent study found that taking very high doses of vitamin D increases the production of an enzyme which inactivates vitamin D in the body -- which may help to explain why taking very high-dose vitamin D has been linked with adverse effects such as muscle weakness and increased risk of fractures and falls in previous studies. For details, see the "How Much Do You Need?" section of the Vitamin D Supplements Review (which includes our tests of products) >>
Better Executive Functioning with Vitamin D -- (3/6/2017) Getting adequate vitamin D appears to help with executive functioning and attention in adolescents, according to a new study — similar to what has been preliminarily shown in men. For details, see the "What It Does" section of the Vitamin D Supplements Review (which includes our tests of products) >>
Statin Drugs and Vitamin D -- (3/4/2017) If you take a statin drug to lower cholesterol, take note that recent studies show it is particularly important that you keep up your level of vitamin D. Also be aware that vitamin D supplements may not raise your vitamin D level quite as much as if you were not taking a statin. For details, see the "Statin Drugs and Vitamin D" section of the Vitamin D Supplements Review (which includes our tests of products) >>
Vitamin D Reduces Risk of Colds & Flu -- (2/16/2017) A study released today shows that taking vitamin D in a certain way reduces the risk of cold and flu infections by up to 70%. The benefits are greatest for people very deficient in vitamin D. For details, see the "What It Does" section of the Vitamin D Supplements Review (which includes our tests of products) >>
Headache and Vitamin D -- (1/7/2017) A large study of middle-aged men found that those with low levels of vitamin D in their blood were twice as likely to have frequent headaches as men with higher levels. For details, see the "What It Does" section of the Vitamin D Supplements Review >>
Vitamin D and Autism Risk -- (12/17/2016) Children whose mothers are vitamin D deficient during pregnancy are much more likely to have autistic traits by age six than those whose mothers have sufficient levels during pregnancy, according to a new study. Get the details, as well as our reviews of vitamin D supplements, in the "What It Does" section of the Vitamin D Supplements Review »
Vitamin D for Autism -- (12/13/2016) A recent study among young children with autism found that high-dose vitamin D reduced autism symptoms from moderate to mild. This is a preliminary study and more research is required. For details about this study and other uses of vitamin D, as well as our tests and comparisons of products, see the "What It Does" section Vitamin D Supplements Review »
Vitamin D Keeping You Up? -- (12/8/2016) A study of women given daily doses of vitamin D found that those who achieved the highest blood levels of vitamin D experienced a deterioration in the quality of their sleep. This is consistent with an earlier study showing decreased production of melatonin with high-dose vitamin D. For details, see the "Concerns and Cautions" section of the Vitamin D Supplements Review >>
Understanding How Much Vitamin D You Need -- (11/16/2016) Misunderstanding the daily requirement for vitamin D is common and can have adverse implications. To address this issue, leading experts recently published an article re-explaining the requirements. We've summarized this in the "How Much Do You Need and How Much Is Too Much?" section in the Vitamin D Supplements Review >>
Vitamin D & Breast Cancer Survival -- (11/12/2016) A new study making headlines this week found that women with "the highest" levels of vitamin D had better survival rates from breast cancer than women with the "lowest rates." What was left out of news stories — and may surprise you — is what these levels are. Find out in the "What It Does" section of the Vitamin D Supplements Review >>
Vitamin D Spray -- (10/31/2016) A study found that vitamin D oral spray was no better than capsules in raising vitamin D levels in healthy men and women. However, a similar study in people with intestinal conditions that can affect absorption suggests a spray may be better. For details (as well as our ratings of products), see the ConsumerTips section of the Vitamin D Supplements Review >>
Vitamin D Sweet Spot -- (10/20/2016) Having the right blood levels of vitamin D has many proven benefits, but too little and too much vitamin D can be problematic. A new study shows this also to be true in people with diabetes with regard to a type of nerve damage that can affect blood pressure and heart rate. For details see the "What It Does" section of the Vitamin D Supplements Review >>
Raising Vitamin D Levels May Reduce Risk Factor For Breast Cancer -- (9/14/2016) A study among postmenopausal women showed that raising vitamin D blood levels helps reduces blood estrogens, which are a known risk factor for breast cancer. And there’s something that reduces estrogen levels even more! For more details, see the "What It Does - Cancer" section of the Vitamin D Supplements Review >>
Vitamin D & Asthma -- (9/7/2016) A daily, moderate dose of vitamin D reduces hospitalizations and use of steroid medication in people with mild to moderate asthma, according to a new study. Get the details in the "What It Does" section of the Vitamin D Supplements Review >>
Vitamin D, Blood Sugar & Insulin Resistance -- (8/20/2016) Vitamin D, Blood Sugar & Insulin Resistance --A moderate, daily dose of vitamin D had positive effects on blood glucose and insulin sensitivity in healthy men and women who largely were deficient in vitamin D, according to a new study. Get the details in the Vitamin D Supplements Review >>
Vitamin D for Asthma -- (8/2/2016) Short term supplementation with vitamin D improved symptoms of asthma in children, according to a new study. Get the details in the "What It Does" section in our Vitamin D Supplements Review >>
Vitamin D & Fatty Liver -- (7/12/2016) Vitamin D supplementation may decrease fat accumulation in the liver in people with non-alcoholic fatty liver disease who are vitamin D deficient. Get the details in the "What It Does" section of the Vitamin D Supplements Review >>
Osteoarthritis and Vitamin D -- (6/4/2016) A large, long-term study among older people with knee osteoarthritis found no benefit from taking vitamin D. More details about this -- and about vitamin D for many other conditions -- are found in the "What It Does" section in our Vitamin D Supplements Review >>
Vitamin D and Cancer -- (4/20/2016) Several studies, including one published this month, show that sufficient levels of vitamin D in the body are associated with decreased risk of various forms of cancer. What’s the best level? See "Cancer" in the What It Does section of the Vitamin D Supplements Review >>
Vitamin D and Allergy -- (4/17/2016) Vitamin D is known to modulate the immune system. Having sufficient levels is associated with reduced risk of allergy and asthma. A recent study showed that giving vitamin D to pregnant women and their infants resulted in fewer infants being allergic to house dust mites and needing to see a doctor for asthma. For details, see "Allergy," as well as "Asthma," in the What It Does section of the Vitamin D Supplements Review >>
Too Much Vitamin D Weakens Legs -- (4/12/2016) In recent months we have reported that giving too much vitamin D to people who don’t need it increases the risk of falls. A major study now shows that it also weakens leg muscles — apparently to the surprise of the researchers. Keep in mind that giving vitamin D to people who are deficient in it can decrease the risk of falls. Get the details in the Vitamin D Supplements Review >>
Vitamin D Improves Heart Output -- (4/5/2016) A recent study in people with chronic heart failure (poor heart output) found that vitamin D improved heart output. However, the study did not achieve its main objective — to increase walking distance. The dose may have been to blame. For details see the "What It Does" section of the Vitamin D Supplements Review >>
Vitamin D and MS -- (3/15/2016) A study found that children born to women significantly deficient in vitamin D during pregnancy were much more likely to develop multiple sclerosis as adults. For details, see the "What It Does" section of the Vitamin D Supplements Review >>
Knee Arthritis & Vitamin D -- (3/8/2016) People with knee osteoarthritis (worn joints) and generally low vitamin D levels given vitamin D for 2 years showed greater improvement in some, but not all, symptoms compared to those given a placebo. Get the details (as well as our product test results) in the Vitamin D Supplements Review >>
Vitamin D and Prostate Cancer -- (3/5/2016) A recent study looked at the association between vitamin D blood levels and the risk of advanced prostate cancer. Based on the findings from this and related studies, there seems to be a reasonable approach with vitamin D to potentially lower prostate cancer risk. Get the details (as well as our tests of products) in the Vitamin D Supplements Review >>
Vitamin D Needed For Nursed Infants -- (2/19/2016) A recent study found that the longer a child is nursed, the higher the risk of being deficient in vitamin D. See the details and recommendations in the Vitamin D Supplements Review >>
Football & Vitamin D -- (2/6/2016) The outcome of today's Super Bowl 50 may be influenced by players' levels of vitamin D. Several studies show that having the right amount of vitamin D in the body reduces the risk of falls in the elderly, but research also shows benefits for younger adults — including fewer injuries among NFL football players. Get the details in the Vitamin D Supplements Review and enjoy the game!
Vitamin D Reduces PMS Symptoms -- (1/23/2016) A recent study found that taking vitamin D significantly improved symptoms of premenstrual syndrome (PMS) in young women who were deficient in vitamin D. Get the details in the Vitamin D Supplements Review >>
Ideal Vitamin D Levels to Reduce Cardiovascular Risk? -- (11/21/2015) A study of a large group of Americans found that the risk of developing cardiovascular disease was 35% higher in people with low levels of vitamin D. Get the details, plus more about maintaining healthful blood levels of vitamin D, and our tests of products, in the Vitamin D Supplements Review >>

Be aware that there is also a risk of getting too much vitamin D >>
Too Much Vitamin D Can Increase Colds -- (11/8/2015) A recent study in people with asthma found that giving high-dose vitamin D increased the risk of developing a cold among those who achieved higher levels of vitamin D or were African-American. Nearly half of those in the study were not vitamin D deficient to start. In contrast, studies have found that giving moderate doses of vitamin D to people who are vitamin D deficient decreases the risk of colds. The point, in our opinion: Maintain an adequate, but not excessive, level of vitamin D. For details (including dosage, levels, and our tests of products) see the Vitamin D Supplements Review >>
Headlines Saying "Vitamin D and Calcium Don't Prevent Colon Cancer" Are Not Quite Right -- (10/17/2015) A study released this week found that vitamin D and calcium supplements did not reduce the risk of developing colorectal polyps in people prone to them. A closer look at the study, however, suggests that this may not be true for everyone. Get the details in the update in the Vitamin D Supplements Review >> and the Calcium Supplements Review >>
Vitamin D Reduces Risk of Falls -- (10/3/2015) A study found that giving a modest daily dose of vitamin D significantly reduced the rate of falls in women who were prone to falls and were deficient in vitamin D. Get details about this and other studies, as well as results of our product tests, in the Vitamin D Supplements Review >>
Adequate Vitamin D Reduces Frequent Respiratory Infections -- (9/20/2015) A study in people with frequent respiratory infections found that taking vitamin D for one year resulted in fewer infections than taking placebo. In contrast, a similar study did not find a benefit. Why the difference? Find out in the Vitamin D Supplements Review >>
Adequate Vitamin D May Lower Risk of Alzheimer's -- (9/16/2015) A study showed that men and women with adequate levels of vitamin D in their blood were less likely to experience declines in cognitive functioning associated with Alzheimer’s dementia than those with lower levels. More about the study, including the vitamin D level considered adequate, as well as our reviews of supplements, is found in the Vitamin D Supplements Review >>
Vitamin D Increases Strength -- (9/2/2015) A recently published review of clinical studies found that supplementing with vitamin D can improve muscle strength in young, healthy men and women. This has also been found in older individuals and may relate to the fact that vitamin D receptors occur in skeletal muscle. However, this benefit may be limited to vitamin D deficient individuals. Get the details in the "Muscle, balance and falls" section of the Vitamin D Supplements Review >>
Vitamin D Reduces Risk of Falls -- (8/19/2015) A recent study found that in older adults, many of whom had insufficient levels of vitamin D and a history of falls, vitamin D supplementation reduced the number of reported falls by almost half. Get the details, including dosage, and our tests of popular products, in the Vitamin D Supplements Review »
More Evidence Against Too Much Vitamin D -- (8/5/2015) A well-controlled study has shown that post-menopausal women do not benefit from taking vitamin D when they are not truly deficient. Get the details on appropriate dosage and use of vitamin D, as well as product test results, in the Vitamin D Supplements Review >>
Vitamin D and Inflammation -- (8/2/2015) A new study of elderly people given vitamin D showed little effect on markers of inflammation in the body. Correcting very low levels of vitamin D may be helpful, but further raising vitamin levels does not seem necessary for proper immune function. In fact, there may be some downside. For details about this and other uses for vitamin D (and our product test results), see the Vitamin D Supplements Review >>
High-Dose Vitamin D Increases Upper Respiratory Infections -- (6/17/2015) A study among older people found that taking a high dose of vitamin D every 2 months increased the risk of upper respiratory infection by 48% compared to taking low-dose vitamin D daily. Infections lasted two days longer for those taking the high dose versus the low dose. For details, including dosage, as well as our test reports on vitamin D supplements, see the Vitamin D Supplements Review >>
Adding Vitamin D to Statin Treatment -- (5/27/2015) A recent study among people taking statin medication for high cholesterol showed significant improvements in cholesterol levels when daily vitamin D was added as treatment. Improvements were greatest among those who began with lower blood levels of vitamin D. More details, along with our reviews of products similar to the one used in this study, are found in the Vitamin D Supplements Review >>
Vitamin D Strengthens Muscle -- (5/20/2015) In a recent study, a modest daily dose of vitamin D led to impressive gains in leg strength in women who were deficient in the vitamin. Details about this study (including dosage) and other studies of vitamin D, along with our reviews of products, are found in the Vitamin D Supplements Review >>
Too Much Vitamin D -- (5/2/2015) A U.S. study showed a recent 26-fold increase in the percentage of people with excessive blood levels of vitamin D, driven by increased supplement use. Although acute toxic effects were rare, potential long-term risks exist with these high levels. See the details in Vitamin D Supplements Review >>
Vitamin D and Statin-Related Muscle Pain -- (4/15/2015) Taking high doses of vitamin D may reduce statin-related muscle pain in people with low blood levels of vitamin D, according to a new study. Get more information and our test reports on vitamin D supplements in the Vitamin D Supplements Review >>
Vitamin D for Diabetic Neuropathy -- (4/1/2015) Supplementing with vitamin D can reduce pain and symptoms of diabetes-related peripheral neuropathy in people with type 2 diabetes who are vitamin D deficient, a recent study reports. More about the use of vitamin D in diabetes and many other conditions, as well as our product test results, are found in the Vitamin D Supplements Review >>
Vitamin D and Reducing Injuries From Falls -- (3/25/2015) Although vitamin D may be able to reduce the risk of falls in women deficient in vitamin D, a new study shows that, among women with sufficient vitamin D, it does not help and may have a negative effect. At the same time, the study showed that an exercise regime cut the rate of injuries from falls by half. Get more details in the Vitamin D Supplements Review >>
Vitamin D for Blood Pressure? -- (3/21/2015) Low levels of vitamin D in the blood are associated with high blood pressure. However, a recent review of many studies concludes that giving vitamin D doesn't help lower blood pressure. For more details about this and other potential uses of vitamin D, as well as our test-based reviews of products, see the Vitamin D Supplements Review >>
Vitamin D Helps in Pregnancy -- (3/7/2015) A new study showed that giving vitamin D to women with low levels of vitamin D resulted in a dramatic reduction in pre-term labor, pre-eclampsia, and gestational diabetes compared to untreated women. For details, see the Vitamin D Supplements Review >>
Vitamin D and Colorectal Cancer -- (1/17/2015) Higher blood levels of vitamin D are associated with a reduced risk of colon cancer, and a new study shows this association to be strongest with a particular subtype of colon cancer. The risk of this cancer in those with higher vitamin D levels is only 10% of that in those with low levels. For details about this and the uses of vitamin D, as well as our ratings of vitamin D supplements, see the Vitamin D Supplements Review >>   
Vitamin D for COPD -- (12/3/2014) A study of people with chronic obstructive pulmonary disease (COPD) found that taking vitamin D significantly reduced the risk of moderate to severe exacerbation, but only among people who began the study deficient in vitamin D. Get the details and information about other uses of vitamin D, along with our quality ratings of vitamin D supplements, in the Vitamin D Supplements Review >> 
Take Vitamin D with a Meal Containing Fats -- (11/26/2014) We've been suggesting this for years and a new study re-emphasizes the point. Get the details in the ConsumerTips section of the Vitamin D Supplements Review >> 
Risk of Bone Fracture Higher With Too Much and Too Little Vitamin D -- (9/27/2014) A large study in elderly men identified a range of vitamin D blood levels associated with the lowest risk of experiencing a bone fracture. Risk nearly tripled among men with higher levels of vitamin D as well as among those with very low levels. For details, including the range of vitamin D associated with lowest risk of fracture, see the update in the Vitamin D Supplements Review >>  
Vitamin D for Asthma -- (9/27/2014) A pilot study in older people with asthma found that daily supplementation with vitamin D improved symptoms among those with uncontrolled asthma. These people were also most likely to have had low blood levels of vitamin D to start. Get the details, including the dose used, and more information about the role of vitamin D in asthma, in the updated Vitamin D Supplements Review >> 
Lower Risk of Surgical Complications with Sufficient Vitamin D -- (8/20/2014) A recent study found that higher blood levels of vitamin D were associated with lower risk of developing serious post-operative complications, including death. As in other studies, the apparent benefit of higher levels of vitamin D increased only up to a point. Get the details in the update to the Vitamin D Supplements Review >> 
Up To a Point, Alzheimer's Risk Falls with Vitamin D -- (8/8/2014) A new study shows that, up to a point, the risks of developing Alzheimer’s disease and other forms of dementia fall with higher blood levels of vitamin D. However, the research also clarifies that exceeding a certain blood level of vitamin D provides no further benefit. In fact, additional research suggests that too much vitamin D can have negative effects. The message: Make sure you have a sufficient, but not excessive level of vitamin D. For details about these levels, as well as results of our tests of vitamin D supplements, see the updated Vitamin D Supplements Review >> 
Vitamin D & Calcium for Diabetes Due to Pregnancy -- (7/12/2014) A new study found supplementation with a combination of vitamin D and calcium improved fasting blood sugar levels, serum insulin levels, and insulin sensitivity in women with gestational (pregnancy-related) diabetes. For more details, including dosage, as well as our tests and comparisons of vitamin D and calcium supplements, see the update to the Vitamin D Supplements Review (Including Calcium, Vitamin K, Magnesium) >>   
Vitamin D May Help Lower Blood Pressure -- (6/24/2014) A recent study in people with mild to moderate high blood pressure showed that taking a vitamin D supplement helped lower blood pressure. Subjects in the study were already taking a calcium channel blocker (nifedipine), but taking vitamin D reduced blood pressure by several additional points. For details, including the dose of vitamin D used, as well as our tests of vitamin D supplements which can provide this dose, see the updated Vitamin D Supplements Review (Including Calcium, Vitamin K, and Magnesium) >>    
Vitamin D and Rheumatoid Arthritis -- (6/13/2014) A recent study shows that people with rheumatoid arthritis tend to have significantly lower levels of vitamin D in their blood than healthy individuals of the same age, gender and body weight. More details, including the vitamin D levels in these groups, is found in the update to the Vitamin D Supplements Review >>   
Vitamin D Helpful for Asthma? -- (5/21/2014) A recent study reported that giving high-dose vitamin D to asthma patients did not significantly reduce the rate of failure with conventional medications. However, a closer look at the study suggests that this conclusion is misleading and that a benefit may exist. Get the details in the update to the Vitamin D Supplements Review >> 
Study Suggests Vitamin D Level for Blood Sugar Control -- (5/11/2014) A certain minimum level of vitamin D in the blood is associated with normal control of blood sugar, according to a recently published study. The study focused on women who were overweight or obese but not diabetic. The vitamin D level is consistent with the range suggested by many other studies. For more details, as well as our tests of vitamin D supplements, see the updated Vitamin D Supplements Review >> 
Vitamin D Deficiency May Predict Advanced Prostate Cancer -- (5/3/2014) According to a new study, prostate biopsies in men who are deficient in vitamin D are more likely to show a higher grade and stage of cancer than biopsies in men with higher levels of vitamin D. For more details, as well as our tests of vitamin D supplements, see the Vitamin D Supplements Review >> 
Reduced Risk of Death with Vitamin D -- (4/6/2014) A recent review of clinical studies involving vitamin D concluded that supplementation with vitamin D-3 significantly reduced overall mortality among older individuals by 11%, while vitamin D-2 had no overall effect. The review did not define exactly when or how much vitamin D is most effective, but you can find sensible guidelines in the Summary section of the Vitamin D Supplements Review >> 
Vitamin D for Weight? -- (3/29/2014) A study of overweight women who were dieting and exercising found that taking vitamin D did not increase the amount of weight they lost. Those attaining the highest blood levels of vitamin D did lose more weight than other women, but this may not have been due to vitamin D. For details about the study, information about other uses of vitamin D, and our tests of vitamin D supplements, see the updated Vitamin D Supplements Review >> 
Vitamin D and Breast Cancer Survival -- (3/8/2014) A new analyses of clinical studies found that women with the highest blood levels of vitamin D had a much higher rate of survival from breast cancer than women with the lowest levels. Details on what may be the most beneficial levels, as well as our test results for vitamin D supplements, are found in the updated Vitamin D Supplements Review >>  
Vitamin D Helps Fibromyalgia -- (1/18/2014) Fibromyalgia is an inflammation of the muscle and soft tissue which causes pain and fatigue. A recent study found that giving vitamin D reduced the pain associated with fibromyalgia. For details about the dose and target vitamin D blood level in the study, as well as our tests of vitamin D supplements, see the updated  Vitamin D Supplements Review >>   
Lower Vitamin D in Blacks May Be Sufficient -- (11/28/2013) The traditional method of assessing vitamin D levels may not be appropriate for most black people, according to a new study. Due to a genetic variant, this approach classifies many black individuals as "deficient" in vitamin D although their levels may be adequate. For details see the update to the  Vitamin D Supplements Review >> 
Vitamin D for Post-Menopausal Women -- (10/6/2013) A study compared the effects of low-dose and high-dose vitamin D on bone mineral density in post-menopausal women who were also supplemented with calcium. Both dosages helped prevent loss of bone mineral density, but the higher dose was less efficient in reducing bone turnover, i.e., bone loss, contrary to what the researchers expected.  For details, including dosage, see the updated Vitamin D Supplements Review>>
Vitamin D for Adolescents -- (10/6/2013) A study found that vitamin D supplementation increased bone density in the hips of adolescent girls, but not of boys. Interestingly, a high dose appeared to have less effect than a low dose. For details, including dosage and our tests of vitamin D supplements, see the updated Vitamin D Supplements Review>>
When Vitamin D Doesn't Help -- (9/29/2013) A recent study in postmenopausal women in New York showed that taking a vitamin D supplement did not reduce bone loss (based on measurements of markers of bone turnover). However, calcium supplementation did appear to help. Why? It all has to do with how much vitamin D and calcium the women were already getting without the supplements. You can find out the amounts and get more details in the update to the Vitamin D Supplements Review >>
Vitamin D for Hypertension? -- (8/18/2013) Some studies have suggested a modest reduction in high blood pressure with vitamin D supplementation. However, a recent study did not find such a benefit - although a closer look reveals why these results may not tell the full story. Get the details, plus more information about vitamin D and cardiovascular health, and test results for 55 vitamin D supplements, in the updated Vitamin D Supplements Review >>
Vitamin D May Protect Bones From Aging -- (7/21/2013) Researchers recently analyzed bone samples from people who were deficient in vitamin D and found changes indicating that the bone had "aged" and was more brittle than bone from people not deficient in vitamin D. For details about this study -- including the levels of vitamin D associated with Vitamin D May Protect Bones from Aging -- Researchers recently analyzed bone samples from people who were deficient in vitamin D and found changes indicating that the bone had "aged" and was more brittle than bone from people not deficient in vitamin D. For details about this study -- including the levels of vitamin D associated with these changes, studies of other effects of vitamin D, as well as test results and comparisons for 55 vitamin D supplements, see the updated Vitamin D Supplements Review >>   
Vitamin D & Depression -- (6/30/2013) Women with depression and type 2 diabetes were given high-dose vitamin D for several weeks in a small, pilot study. By the end of the study, vitamin D levels in the blood had risen considerably and mood was significantly improved, as was blood pressure. Although just a pilot study, this is not the first study to suggest that vitamin D may help with depression. For more details, as well as test results and comparisons for 55 vitamin D supplements, see the updated Vitamin D Supplements Review >>
Does Vitamin D Prevent Ear Infection? -- (6/9/2013) Maintaining adequate levels of vitamin D in children appears to reduce mild ear infections, but too much vitamin D may have a downside. Find out the details in our updated Vitamin D Supplements Review >>
Optimum Level of Vitamin D -- (5/19/2013) New research shows that blood levels which are too low or too high for vitamin D are associated with increased risk of heart attack and earlier death. Find the "sweet spot" for vitamin D levels as well as test results for 55 vitamin D supplements in the updated Vitamin D Supplements Review >>
Vitamin D for Infants -- (5/12/2013) How much is needed and how much is too much? A new study sheds light on what's appropriate for infants. Get the facts and our tests of 55 vitamin D supplements (including baby drops) in the updated Vitamin D Supplements Review >>
Vitamin D & Pneumonia -- (5/5/2013) A new study in men and women ages 53 to 73 found that a low vitamin D level in the blood was almost as strong a risk factor for pneumonia as smoking! Get the details, including the level with lowest risk of pneumonia, in the updated Vitamin D Supplements Review >>
Lower Risk of Fibroids With Vitamin D -- (5/5/2013) A study of women in Washington, D.C. showed that those with higher blood levels of vitamin D had a 32% lower risk of uterine fibroids -- the most common reason for hysterectomy. Unfortunately, most of the women had less than sufficient levels of vitamin D. Find out the levels associated with lowest risk of fibroids, learn how to improve vitamin D levels (without overdoing it), and get the results of our latest product tests in the Vitamin D Supplements Review >>
Vitamin D and Knee Arthritis? -- (1/13/2013) Can taking vitamin D reduce the pain and progression of osteoarthritis of the knee? A new study found no benefit for people who already had sufficient levels of vitamin D. In fact, these people needed more anti-inflammatory medication during the study than those given placebo. However, as seen in many other studies of vitamin D, people who entered the study deficient in vitamin D appeared to benefit from being given vitamin D, experiencing reduced pain. For more details, see the update in the Vitamin D Supplements Review, which includes our tests of vitamin D supplements. If you suffer from osteoarthritis of the knee or other joints, also read about glucosamine and chondroitin, as supplements with these ingredients may help. We have tested many of these products.
Vitamin D and Pregnancy -- (1/6/2013) A recent study shows that low levels of vitamin D in pregnant women are associated with a higher risk of babies born small for their gestational age. For details, see the update in the Vitamin D Supplements Review, which includes our tests of vitamin D supplements and extensive information about the use of vitamin D. More >>
Vitamin D and Diabetes Risk -- (12/2/2012) A new study shows a strong association between lower levels of vitamin D in the blood and a higher risk of developing type 1 diabetes (i.e., requiring insulin). The risk of diabetes was more than 3.5 times as great among people with low levels of vitamin D compared to those with higher levels -- although no additional benefit was found for people with the highest levels of vitamin D. Find out more -- including the specific level associated with the lowest risk of type 1 diabetes -- in the updated Vitamin D Supplements Review, which includes our test results for 51 vitamin D supplements. More >>
Vitamin D and Bladder Cancer -- (11/4/2012) A new study looked at vitamin D levels and the risk of developing bladder cancer. Find out which levels were best, as well as which vitamin D supplements pass our tests, in the updated Vitamin D Supplements ReviewMore >>
Large Study Suggests Best Vitamin D Level -- (10/28/2012) What's the best level of vitamin D in your body for overall health? One way to answer this question is to compare mortality rates (deaths per year) associated different levels of vitamin D. A new study did just this, reviewing information about thousands of Americans. It concluded the best levels are between 20 and 40 ng/mL, as the risk of dying is fairly similar across this range. However, a closer look at the findings suggests an even smaller range actually associated with the lowest mortality. For the details, as well as our suggestions on how to use vitamin D, and quality ratings of products, see the Vitamin D Review.  More >>
Vitamin D for Lupus -- (10/21/2012) A recent small study found that vitamin D supplements helped people with lupus (systemic lupus erythematosus -- SLE), a long-term autoimmune disease. See the update to the Vitamin D Supplements Review which has details on who may benefit, dosage, and results of our product tests. More >>
Does Vitamin D Prevent Colds? -- (10/7/2012) A recent study found vitamin D supplementation did not reduce the number or severity of colds, but a closer look suggests that it can, depending on your vitamin D level. Get the details and our ratings of 51 vitamin D supplements in the updated Vitamin D Supplements Review >>
Vitamin D & Alzheimer's -- (9/16/2012) A seven-year study of women over age 75 found those with higher intakes of vitamin D from their diets were 77% less likely to develop Alzheimer's disease. The amount of vitamin D intake associated with this large benefit was actually fairly modest. Get the details in the updated Vitamin D Supplements Review, which includes our product tests and quality ratings. More >>
Vitamin D Speeds Recovery from Tuberculosis -- (9/16/2012) A study in London found that adding vitamin D to standard antibiotic treatment for tuberculosis significantly reduced inflammation and speeded recovery. The majority of these patients, however, had been extremely deficient in vitamin D. Get the details in the updated Vitamin D Supplements ReviewMore >>
Low Vitamin D Levels and Obesity -- A Dangerous Combination -- (8/19/2012) A new study links low blood levels of vitamin D in obese individuals to a greatly increased risk of insulin resistance (a condition linked to type 2 diabetes). The results add to the growing list of reasons to make sure you maintain a sufficient level of vitamin D. Get the details in the latest update to ConsumerLab.com’s Vitamin D Supplements ReviewMore >>
Is Vitamin D2 or D3 Better? -- (8/2/2012) Over the years, studies have shown vitamin D3 to be either equal to or better than vitamin D2 for raising vitamin D blood levels. A new study further tips the scales. Get the details, as well as our tests of vitamin D supplements, in the updated Vitamin D Supplements ReviewMore >>
Vitamin D Prevents Hip Fracture -- (7/22/2012) We recently reported that a U.S. Task Force found it unclear if vitamin D prevented hip fracture, but a more recent report found otherwise. The new report suggests a specific minimum blood level of vitamin D to help prevent fractures, the dosage found most effective, and the frequency at which vitamin D should be taken. Get the details in the recent update to the Vitamin D Supplements Review, which includes our tests of vitamin D supplements.  More >>
Vitamin D Tests Unreliable -- (7/1/2012) A preliminary report suggests that many vitamin D blood tests are incorrect, often yielding low results. This can lead to the diagnosis of vitamin D deficiency when it does not exist. Certain people may be more prone to a false low reading due to their source of vitamin D. Learn more in the update to the Vitamin D Supplements Review entitled Vitamin D Tests -- Not Always Reliable >>
Does Vitamin D Help Manage Weight? -- (7/1/2012) If you've been reading our recent newsletters, many reports are being published about the effects of vitamin D. Here's one more: People with higher levels of vitamin D tend to put on less weight than people with lower levels. See the details in the update to the Vitamin D Supplements ReviewMore >>
Don't Take Vitamin D? -- (6/17/2012) Recommendations were published this week by an expert panel against the use of certain combinations of vitamin D and calcium in postmenopausal women to prevent fractures -- as the risks outweighed the benefits. However, this does not mean you shouldn’t take vitamin D. In fact the experts recommended that people at increased risk for falls should take vitamin D.  

Find out exactly what was recommended! Read the update to the Vitamin D Review. You’ll get a more complete picture of what vitamin D supplements can and can’t do, the latest information on what levels of vitamin D in your body seem optimal for overall health, and our test findings for vitamin D supplements. More >>
Too much vitamin D may increase the risk of dying -- (6/3/2012) A recent study of nearly a quarter million people found those with vitamin D levels above that considered sufficient, but not much higher, had the lowest risk of dying over the study period. People with high levels of vitamin D were more likely to have died. Some earlier research suggests the same. What does this mean for you? See our update to the Vitamin D Supplements Review for more information. More >>
Vitamin D and the Risk of Death -- (4/1/2012) In a six-year study of over 10,000 people in Kansas, the risk of death was found to be 164% higher among those with lower levels of vitamin D in their blood. These people were also more likely to suffer from hypertension, coronary artery disease, cardiomyopathy, and diabetes than those with higher levels. Only 29% of the people in the study had the higher level of vitamin D. For details, including the level of vitamin D associated with lower risk of death, ways to boost vitamin D, tests of vitamin D supplements, and more, see the Vitamin D Review >>
Vitamin D Effect on Body Fat and Cholesterol -- (3/11/2012) As we have reported earlier, adequate intake of vitamin D may decrease the risk of cardiovascular disease. A new study may help explain why. A 12-week course of vitamin D given to overweight women lead to a boost in HDL ("good" cholesterol) as well as a decrease in body fat. However, total body weight did not change and there was an increase in LDL ("bad") cholesterol, although it appeared to be less plaque-forming in nature. For details, including the dose given, see the updated information in the Vitamin D Supplement ReviewMore >>
Strength Improves with Vitamin D -- (3/11/2012) A review of 13 studies found that vitamin D supplements may improve balance and muscle strength, but not gait, among older individuals. See the update to the Vitamin D Supplements Review for details, including dosage. More >>
Vitamin D to Prevent Menstrual Pain -- (3/11/2012) A new study found that taking a very high dose of Vitamin D reduced pain by 41% for two months among women who suffer from painful menstrual cramps. However, there are potential concerns with such a high dose of vitamin D. For more information, including the dose used and potential concerns, see the update to the Vitamin D Supplements ReviewMore >>
Vitamin D and Inflammation -- (1/22/2012) A new study found that raising low levels of vitamin D appears to reduce inflammation in the body (based on measurements of C-reactive protein, or CRP, a marker of inflammation). However, once vitamin D levels reached what some people consider to be barely sufficient, CRP slowly but progressively increased, suggesting an inflammatory action of vitamin D at higher levels. The study raises the question of what is the ideal level of vitamin D in the body. 

Be sure you have the latest information! See the update to the Vitamin D Supplements Review, which includes details on this and other vitamin D studies, as well as our latest product tests.
Vitamin D and Pancreatic Cancer -- (1/8/2012) A lower risk of developing pancreatic cancer was recently associated with higher levels of vitamin D in the body. See the update to the Vitamin D Supplements Review for the vitamin D levels associated with decreased pancreatic cancer risk, as well as our ratings of vitamin D supplements.
More Vitamin D for Obese Adolescents -- (11/29/2011) Vitamin D is fat soluble, so obese people who are deficient in it need more than other people to increase their vitamin D levels. A recent study in obese adolescents showed just how much more they need. It also determined that a relatively high dose of vitamin D was safe in these adolescents. For details, including the dosage used, see the update to the Vitamin D Supplements Review, which includes ConsumerLab.com's quality ratings and comparisons of vitamin D supplements.
How to Boost Your Vitamin D! -- (9/21/2011) A study of people whose vitamin D levels did not rise enough despite taking a supplement found that just changing when the supplement was taken boosted vitamin D levels by 50%. To find out how and to get more details, see the recent update to the Vitamin D ReviewMore >>
Vitamin D - Depression Link -- (9/11/2011) A study of postmenopausal women found the risk of depression to be 21% lower among those consuming higher amounts of vitamin D. For details, including the vitamin D source and amounts associated with decreased risk, see the update to the Vitamin D ReviewMore >>
Vitamin D and Diabetes Risk -- (8/2/2011) A recent report showed that the risk of developing type 2 diabetes increases when vitamin D intake is low. The increased risk of diabetes is even more dramatic when vitamin D in the blood is below adequate levels. Get the details in the update to the Vitamin D Supplements Review >>.
Kidney Stones Linked to Calcium and Vitamin D Supplementation -- (7/20/2011) A recent report showed that women taking a calcium and vitamin D supplement over a period of several years were 17% more likely to develop kidney stones than women who did not take the supplement. ConsumerLab.com reviewed this study. While the findings are correct, there seems to be no reason to give up vitamin D supplements and a small concern with calcium supplementation. Get the details in the update to the Calcium Supplements Review >>. The new information is also found in an update in the Vitamin D Supplements Review >>.
Does Taking Vitamin D Reduce the Risk of Heart Disease? -- (6/22/2011) Earlier research has suggested an association between higher vitamin D levels in the blood and reduced risk of heart attack. But blood levels are affected by both sun exposure as well as intake of vitamin D. A new study shows that men with higher vitamin D intakes from foods and supplements have a 14% reduction in their risk of cardiovascular disease and stroke. However, the study found no reduction among women. The amount of vitamin D intake shown to be beneficial and possible reasons why a benefit was not found in women are provided in the updated "What It Does" section of our Product Review of Vitamin D SupplementsMore >>
Vitamin D and Allergy? -- (2/27/2011) Recent analyses of data from thousands of individuals across the U.S. show an association between serum vitamin D levels and certain allergies. The association was found in children and adolescents for 11 different allergens, but no association was found in older individuals. See the Vitamin D Product Review for the types of allergies and level of vitamin D at which risk was reduced. More >>
Calcium and Vitamin D for Girls -- (2/2/2011) In a recently published study, girls ages 9 to 13 were given, twice a day, a supplement with calcium and vitamin D. After 6 months, significant increases were found in bone density and strength compared to girls who received placebo. Get the amounts and types of calcium and vitamin D taken, as well as more information, in the Review of Calcium Supplements or the Review of Vitamin D Supplements.




 
 
 


 

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