SEARCH RESULTS for "Vitamin K"

Vitamin K Supplements Reviewed By

Vitamin K Supplements Review (Including Calcium, Vitamin D, Magnesium & Boron)

Learn what to look for to choose the best vitamin K supplement and find out which products passed or failed our quality tests and review. Compare dosage, cost, and formulation. Learn the difference between vitamin K1 and K2, and forms of K2 including MK-7 and MK-4. Get more information on proper dosage, safety and side effects of vitamin K.

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Encyclopedia Articles Found: (Articles do not mention brands)
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1.Vitamin K
5.Antibiotics (General)
10.Vitamin E
... More Results Answers to Questions Found:
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1.I'm considering taking vitamin K for my bones, but I take blood thinner (anti-coagulant) medication. Is there a problem taking both?
2.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?
3.Have you tested vitamin K supplements with MenaQ7? Is this a good source of vitamin K if I need to avoid soy?
4.What is the difference between forms of vitamin K2?
5.Can vitamin K2 really help decrease calcium in the arteries?
6.Can vitamin supplements strengthen brittle nails?  (in Comments)
7.How much calcium from supplements is too much?  (in Comments)
8.I take warfarin (Coumadin), an anticoagulant drug. Are there supplements I should avoid, or be taking, due to this drug?
9.Is it true that green tea can interact with blood-thinning medications like warfarin (Coumadin) or clopidogrel (Plavix)?
10.Is it better to get vitamins from foods or supplements, and are natural vitamins better than synthetic vitamins?
11.Does arnica gel, cream, or spray reduce bruising, pain, or swelling?  (in Comments)
12.Is it true that overdoses of vitamin D only occur when you don't get enough vitamin K?
13.Do any supplements help prevent or treat osteoporosis?
14.Which supplements reduce the risk of stroke? Which increase the risk of stroke?
15.Do any supplements improve balance or reduce the risk of falls?  (in Comments)
16.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?
17.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?
18.Are there any supplements I should avoid when taking an antibiotic? Are there any that may be helpful?
19.Which vitamins and minerals should be taken together or separately?
20.Which "whole food" multivitamins are only from foods and don't include synthetic vitamins? What can you tell from the labels of these products: Complete Foods Nutrition-OctoMega MultiVitamin; Sunwarrior Raw Vitamins; Garden of LIfe-MyKind Organics; Nature's Brands-PhytoVitamins; Doctors' Research MultiVitamin?

Clinical Updates Found:
2020 A Role for Vitamin K in COVID-19? (04/28/2020)
A Role for Vitamin K in COVID-19?
A new study showed a link between vitamin K and the development of COVID-19. Learn what this means in the What It Does section of our Vitamin K Supplements Review. Also see our Top Pick among vitamin K supplements.
 Vitamin K for Bone Density? (02/18/2020)
Vitamin K for Bone Density?
Vitamin K (as MK-7) was given daily for one year to older men and women to see if it would improve bone mineral density. Some also received vitamin D and calcium. Find out if it helped, as well as the results of related studies, in the What It Does section of the Vitamin K Supplements Review. Also see our Top Picks among vitamin K supplements.
2017 How To Get Vitamin K From Food (06/08/2017)
How To Get Vitamin K From Food
Many of the benefits of vitamin K - such as proper blood clotting and calcium utilization for bone and heart health - are associated with getting adequate vitamin K from foods. The good news? Brand new research has found much higher amounts of vitamin K2 (the form associated with cardiovascular benefits) in dairy foods than previously known. However, the amounts vary tremendously depending on whether these foods are full-fat, or reduced-fat or fat-free. Get the details in the "Vitamin K from food" section of the Vitamin K Supplements Review. If you’re interested in a vitamin K supplement, see our Top Picks among brands.
2014 Vitamin D & Calcium for Diabetes Due to Pregnancy (07/12/2014)
Vitamin D & Calcium for Diabetes Due to Pregnancy
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 (06/24/2014)
Vitamin D May Help Lower Blood Pressure
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) >>    
 Too Much Calcium for Some? (06/20/2014)
Too Much Calcium for Some?
A new study found that supplementing with even moderate amounts of calcium may cause abnormally high calcium levels in the urine (a risk factor for kidney stones) of some postmenopausal women, even when total calcium intake doesn't exceed the recommended daily allowance. Get the details in the update to the Calcium Supplements Review (Including Vitamin D, Vitamin K, and Magnesium) >>   
2013 Low Dose of Vitamin K Helps Bone (03/31/2013)
Low Dose of Vitamin K Helps Bone
Using a much lower dose of vitamin K than in previous studies, a new study found that intake of a particular form of vitamin K decreased age-related decline in bone mineral content and density in certain bones in postmenopausal women. Get the details, as well as our ratings of these supplements, in the updated Vitamin K Supplements Review >>

Recent Recalls and Warnings Found:

Archived Recalls and Warnings Found:
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1.Maker of Vitamin K, Vitamin A & More Warned for Manufacturing Violations, Drug Claims (12/29/2015)
2.Seller of Speech Disorder Supplement Agrees to Settle FTC Charges of Deceptive Claims (01/13/2015)
3.Seller of Prostate, Heart Supplements and More Warned for Drug Claims (11/06/2014)
4.Probiotic Recalled Due To Undeclared Soy (03/21/2013)

News Releases Found:
2017 Best Vitamin K Supplement? Tests Popular Products and Reveals Its Top Picks (06/01/2017) Tests Reveal the Best Calcium Supplements (05/26/2017)
 Best Vitamin D? Tests Popular Vitamin D Supplements and Reveals Its Top Picks (05/17/2017)
 Vitamin D Supplements Maintain Top Spot in Popularity, as Probiotics Surpass Multivitamins to #4 Behind Fish Oil and CoQ10 in Latest Survey (02/24/2017)
2016 Helps Consumers Make Sense of the FDA's Updated Daily Values (DV) for Vitamins and Minerals (07/27/2016)
2015 Best Supplements for Bone Health? Finds Products with Multiple Ingredients More Likely to Contain Wrong Amounts (04/28/2015)
 Use of Magnesium and Probiotics Rise, Multivitamins and Weight Loss Supplements Fall, According to Survey (02/28/2015)
2013 Reports Problems with Some Vitamin D and Calcium Supplements -- Wrong Amounts of Vitamin D, Pills Which Don’t Break Apart, and Lead Contamination Found (02/11/2013)
2012 Fish oil and multivitamins most popular supplements in survey -- Internet most popular place to shop (02/05/2012)
2011 Problems discovered with eight vitamin D supplements in study by -- Incorrect amounts of vitamins, lead contamination, and labeling infractions identified. (04/26/2011)
 Vitamin D use increased 52% in past two years according to survey of supplement users -- Fish oil continued to surpass multivitamins as most popular supplement and Internet was most common place to buy supplements (01/31/2011)
2009 reports deficiencies in some supplements containing calcium, vitamin D, or vitamin K -- Focus on bone health supplements and new uses for vitamins D and K (03/10/2009)
2008 Tests of zinc supplements by show only some provide dosage proven to shorten colds, reduce eye disease.  Lead contamination found in one product. (12/09/2008)
 Adulteration Suspected with Some "Memory" Supplements -- Few Ginkgo and Huperzine Supplements Pass Tests; Quality High for Acetyl-L-Carnitine (11/18/2008)
 Tests reveal quality problems with vitamin A supplements -- New report focuses on vitamin A, including beta-carotene and cod liver oil (10/28/2008) finds melatonin supplements range in strength but ingredient quality is high (10/02/2008)'s tests of menopause supplements reveal wide range in strength and quality; mislabeling and contamination discovered -- Soy and red clover isoflavones, black cohosh, and progesterone products tested (09/17/2008) Find Fifty Fish Oil Supplements Pass Quality Testing -- New Report Helps Consumers Choose Among Pills, Liquids, Foods and Beverages with Omega-3 Fatty Acids (EPA and DHA) (08/05/2008)


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