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Vitamin D Supplements Review (Including Calcium, Vitamin K, Magnesium, and Boron)
Summary: What You Need to Know About Vitamin D Supplements
What does it do? There are many reasons to make sure you're getting sufficient vitamin D: These include improved bone health, reduced risk of heart attack and stroke, reduced risk of asthma and allergy, reduced inflammation, and perhaps others. Not surprisingly, over given periods of time there are fewer deaths among people who have the right amount of vitamin D compared to those who have too little or too much. For details, see What It Does.
COVID-19 UPDATE: Preliminary studies suggest that people with lower levels of vitamin D are more likely to test positive for the coronavirus and have more severe symptoms of COVID-19. Vitamin D may also reduce the need for intensive care. See the COVID-19 section for details.
The right level? You may already get enough vitamin D from the sun (about 15 minutes to the face, arms, and hands at least twice a week without sunscreen) and the foods you normally eat. If you're not sure, get your blood level checked by your doctor. A total serum 25-hydroxyvitamin D level of at least 20 ng/mL is considered "sufficient," (note that 20 ng/mL is equivalent to 50 nmol/L), although there may be additional benefit to being in the 25 to 35 ng/mL range. Don't exceed 39 ng/mL. Be aware that people who are black generally have lower total vitamin D levels than whites, but new research suggests these lower levels may be sufficient for blacks. For details see How Much Do You Need and How Much is Too Much?
How much to take? For every 1 ng/mL increase, you'll need to get an additional 100 IU of vitamin D per day (obese individuals may require double the amount). For example, if your blood level is 18 ng/mL, taking 400 IU of vitamin D daily (or 800 IU if you are obese) should get you to about 22 ng/mL. It can take 6 weeks to reach the peak. Keep taking the vitamin D to stay at that level. See recommended daily requirements for vitamin D. (Note that vitamin D is also shown in mcg: each 400 IU of vitamin D is equivalent to 10 mcg). For details, see What to Consider When Using.
When to take it? Take vitamin D supplements with your biggest meal of the day (the one that contains most fats and oils) as this can increase absorption by as much as 50%! For details, see Take Vitamin D with Food.
Top Picks: Choose a supplement that has been Approved by ConsumerLab.com in the Results table below because not all supplements live up to their ingredient claims (See What CL Found). Also, see CL's Top Picks for those offering the best value, dose, and convenience.
Don't overdo it! Studies show that people with the highest levels of vitamin D actually tend to have more bone fractures, fall more frequently, sleep less well, and die sooner than those with lower, but sufficient, levels. If your level is over 20 ng/mL, you probably don't need a supplement. If your level is above 35 ng/mL, taking a supplement may be doing more harm than good, so consider cutting back. For details see How Much Do You Need and How Much is Too Much?
You must be a member to get the full test results along with ConsumerLab.com's recommendations and quality ratings. You will get results for 21 vitamin D supplements selected by ConsumerLab.com and 4 others that passed testing in its voluntary Quality Certification Program.
In this comprehensive review, you'll discover:
Which vitamin D supplements failed our quality ratings and which passed -- including combinations with calcium, magnesium and/or vitamin K
CL's Top Picks for vitamin D supplements
What vitamin D can and can't do for you, and how too much can actually harm you
What is vitamin D, and is vitamin D2 or D3 best for you?
The best way to take vitamin D
What is vitamin D deficiency and how to gauge if your vitamin D levels are sufficient, too low, or too high -- and how this may differ if you are black
Vitamin D dosage based on your age, gender and needs
How to get vitamin D from the sun and from foods
Side effects of vitamin D supplements and potential drug interactions
Question: Is it true that vitamin D can increase the risk of prostate cancer in men? Get the answer >>
Question: How likely are Americans to be deficient in vitamins or minerals? Get the answer >>
Question: Is it better to get vitamins from foods or supplements, and are natural vitamins better than synthetic vitamins? Get the answer >>
Question: Sometimes my powdered supplements get clumpy. Should I be concerned? Get the answer >>
Question: What Is Marine-D3 and does it live up to anti-aging claims? Get the answer >>
Question: Which supplements are important after bariatric surgery (i.e., weight loss or stomach-reducing surgery)? Are there any I should avoid? Get the answer >>
Question: Which supplements can help lower cholesterol and keep my heart healthy? Are there any to avoid? Get the answer >>
Question: As vitamin D is a fat-soluble vitamin, why is it necessary to take it every day? Get the answer >>
Question: I'm thinking of changing my multivitamin, but the one I'm considering doesn't contain molybdenum. Most others have it. How important is molybdenum? Get the answer >>
Question: I have been having dizziness for the past few months and am wondering if it could be a side effect of supplements I take. Which supplements cause dizziness? Get the answer >>
Question: I'm taking Lumiday, a supplement to improve mood. It seems to help me but is it safe? Get the answer >>
Question: Is it better to eat farmed salmon or wild salmon? Which one has more omega-3s and less contamination with PCBs, mercury, etc.? Get the answer >>
Question: Is there cause for concern with "gummy vitamins?" There are many different gummies out there. Are some better than others? Get the answer >>
Question: Which supplements help reduce the risk of colorectal cancer? Get the answer >>
Question: A blood test showed my vitamin D level is low. How do I know how much vitamin D to take? Get the answer >>
Question: I read that aging lowers the body's capacity to produce vitamin D. Even regular sun exposure will not suffice and one may have to take a vitamin D3 supplement during old age to meet our body's regular requirements. Please comment on this. Get the answer >>
Question: I spend a lot of time in the sun, especially in the summer. Does this mean my vitamin D levels could get too high? Get the answer >>
Question: Is there a difference between taking vitamin D in the dry form versus the oil capsules? Is one better than the other? Get the answer >>
Question: Which supplements can help lower or control my blood sugar? Get the answer >>
Question: If vitamin K absorption appears to be reduced by other fat-soluble vitamins, like vitamin D, why do some "bone health" supplements combine them? Should they be taken separately? Get the answer >>
Question: I am having trouble sleeping. I regularly take a multivitamin, fish oil, magnesium, calcium, vitamins D and K, and a protein supplement. I also take a low-dose blood pressure medication. Could any of these supplements be causing my insomnia? Get the answer >>
Question: I've heard it's best to take fat-soluble supplements, like CoQ10, curcumin, and vitamin D, with fats or oils to increase absorption. Would taking them with a fish oil capsule be enough? Get the answer >>
Question: Is it true that overdoses of vitamin D only occur when you don't get enough vitamin K? Get the answer >>
Question: Are there vitamins or supplements that can reduce my risk of breast cancer? Do any increase cancer risk? Get the answer >>
Question: Does taking a laxative interfere with the absorption of vitamins or minerals? Get the answer >>
Question: What are the best supplements for depression and anxiety? Get the answer >>