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B Vitamins Reviewed by

B Vitamin Supplements Review (B Complexes, B6, B12, Biotin, Folate, Niacin, Riboflavin & More)

Read our reviews of B vitamin supplements, to find the best B complexes, niacin, B-6, B-12, biotin, thiamin and folic acid. Get information about B vitamins for energy, memory, and depression. Read about MTHFR and methylfolate, and the safety of energy drinks with B vitamins.

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2.Plant-Based Milks (Almond, Cashew, Coconut, Flax, Hemp, Macademia, Oat, Pea, and Soy)  *
3.Multivitamin and Multimineral Supplements Review  *
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5.Recommended Daily Intakes and Upper Limits for Vitamins and Minerals |
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8.Vitamin D Supplements Review (Including Calcium, Vitamin K, Magnesium, and Boron)  *
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12.Meal Replacement & Weight Management Powders and Shakes Review  *
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Encyclopedia Articles Found: (Articles do not mention brands)
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1.Proton Pump Inhibitors
2.H2 Blockers
3.Nitrous Oxide
4.B Vitamins
8.Bile Acid Sequestrant Drugs
9.Oral Hypoglycemics
10.Fibrate Drugs
... More Results Answers to Questions Found:
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1.Do vitamin patches, such as for B12 or multivitamins, really work? How about those from PatchMD?
2.Being over 50 years old, I'm looking to take a vitamin B-12 supplement. I see that many contain a form of vitamin B-12 called cyanocobalamin, yet I read on the Internet that this form is toxic. Should I be concerned?
3.What is vitamin B12 and how much do I need?
4.Can lysine, vitamin B-12, or other vitamins or minerals help prevent or reduce canker sores?
5.Can prenatal vitamins have too much folic acid? Mine has 800 mcg, but isn't that more than what's recommended? Is this dangerous to me or my baby?
6.I was told I have a MTHFR gene mutation. What do I need to know about taking B vitamins?
7.I've heard that having low B-12 or B-6 can cause depression. Is that true?
8.Is sublingual vitamin B-12 really better than the pill form?
9.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?
10.Can taking too much vitamin B-12 be dangerous? The label on my B-complex states it contains 50,000% of the Daily Value!
11.I read on your website that some B-12 vitamins can cause diarrhea due to added sugar substitutes like sorbitol. I have had diarrhea and never thought it could be caused by my vitamin B-12 supplement, until I read your article and stopped taking the supplement. My diarrhea stopped immediately. Can you help me find a brand of B-12 that doesn't contain sorbitol or sugar substitutes that could cause this problem?
12.Are lozenges and sublingual pills considered dietary supplements?
13.How do the Beyond Burger, the Impossible Burger, and a beef burger compare in terms of vitamins and minerals, and which is best?
14.The maker of my multivitamin says it doesn't include folic acid because too much from supplements can be harmful. Is that true?
15.Which supplements are important after bariatric surgery (i.e., weight loss or stomach-reducing surgery)? Are there any I should avoid?
16.What are the symptoms of B12 deficiency?
17.Do any supplements help for tinnitus? Is it true that some supplements can cause tinnitus?
18.How likely are Americans to be deficient in vitamins or minerals?
19.Are B12 injections "better" than oral supplements? Are they necessary if I have a B12 deficiency?
20.Does vitamin B12 improve memory?
21.What B-vitamin complex do you recommend for older people?
22.Are the "% DV" numbers on vitamin supplement labels really based on what I need?
23.Does taking a laxative interfere with the absorption of vitamins or minerals?
24.Is it better to get vitamins from foods or supplements, and are natural vitamins better than synthetic vitamins?
25.What are natural remedies for coronavirus (COVID-19)? Do supplements like zinc, vitamin C, or herbals work?
26.When is the best time of day to take a multivitamin?
27.Which supplements help to improve energy and decrease fatigue?
28.Do any supplements improve balance or reduce the risk of falls?
29.Can vitamins or other supplements cause a change in the ability to taste, or even a loss of taste?
30.Is there a multivitamin that contains only the recommended daily vitamins and minerals? Most that I have looked at contain more.
31.Which vitamins and supplements are good for acne, and are there any that make it worse?
32.Are enteric coated supplements better than non-enteric coated ones?
33.Do any supplements help with nerve pain, like sciatica or diabetic neuropathy?
34.Do Sugar Bear Hair Vitamins make hair shine, nails stronger, and help both to grow? They taste good but are super expensive.
35.I enjoy oat milk in my coffee, but how healthy is it for me?
36.I was surprised when my doctor told me to stop taking supplements because my kidney function was low. But after stopping the supplements, my kidney function returned to normal. Can taking a lot of supplements really damage the kidneys?
37.Is it true that some vitamins or supplements can cause cancer?
38.Which supplements can cause diarrhea?
39.Is it true that iodine can cause acne or other skin problems?
40.I read that famotidine (Pepcid) may help treat COVID-19. Is this true? Are there risks with taking famotidine?

Clinical Updates Found:
2020 B Vitamins and Fracture Risk (08/06/2020)
B Vitamins and Fracture Risk
High homocysteine levels have been linked with increased fracture risk in older people. Taking B vitamins can lower homocysteine levels, but does it lower fracture risk? Find out what a recent study using folic acid and B12 showed in the What It Does section of the B Vitamin Supplements Review. Also see our Top Picks for B vitamins.
 Vitamin D for COVID-19 Patients (06/02/2020)
Vitamin D for COVID-19 Patients
A study evaluated the effects of giving vitamin D, magnesium, and vitamin B12 to COVID-19 patients. See the results in the COVID-19 section of the Vitamin D Supplements Review. Also see our Top Picks for vitamin D.
 Cognitive Impairment From B12 Deficiency (02/25/2020)
Cognitive Impairment From B12 Deficiency
Vitamin B12 deficiency can cause a wide range of symptoms. This includes cognitive impairment, as shown in a recent case. For details about the symptoms of B12 deficiency see the B12 section of the B Vitamin Supplements Review. Also see our Top Picks for B12 and other B vitamin supplements.
 Vitamin B12 and Risk of Death (02/11/2020)
Vitamin B12 and Risk of Death
A study found higher blood levels of vitamin B12 to be associated with an increased risk of death -- suggesting caution when supplementing. For details, see the B-12 section of the B Vitamin Supplements Review. If you do need to supplement with B12, see our Top Pick among products.
2019 B12 & the Vegetarian (12/14/2019)
B12 & the Vegetarian
Vegetarians and vegans are susceptible to vitamin B12 deficiency, which can be manifest by a range of health issues, including low blood pressure, as recently reported in an otherwise healthy young man. Learn more in the B12 section of the B Vitamin Supplements Review. Also see our Top Pick for vitamin B12.
 B Vitamins for Cognition (11/29/2019)
B Vitamins for Cognition
Increasing vitamin B-12 intake by those deficient in B-12 can help slow age-related declines in memory and cognition, but the dose needs to be sufficient, as suggested by a recent study. For details see the Memory, Cognition, and Alzheimer's Disease section of the B Vitamin Supplements Review. Also see our Top Picks for B-12 and other B Vitamins.
 Vitamin B12 & Sleepiness (09/21/2019)
Vitamin B12 & Sleepiness
Vitamin B12 deficiency can cause a range of symptoms and, although rare, excessive daytime sleepiness is among them. Get the details about this, as well as information about other symptoms of B12 deficiency, in the B12 section of the B Vitamins Supplements Review. Also see our Top Pick for vitamin B12.
 Zinc for Canker Sores? (07/20/2019)
Zinc for Canker Sores?
We've added information about zinc to our answer to the question: Can lysine, vitamin B-12, or other vitamins or minerals help prevent or reduce canker sores?
 Do Vitamin Patches Work? (07/16/2019)
Do Vitamin Patches Work?
We've added important new information to our answer to the question: Do Vitamin Patches Work?
 Vitamin B12 & Depression (05/28/2019)
Vitamin B12 & Depression
Deficiencies in B vitamins, such as B12, can cause depression. A recent study suggests that, in pregnant women, even low-normal B12 levels are associated with a much higher risk of depression. For details, see the Depression section of the B Vitamin Supplements Review. Also see our Top Picks for B vitamins.
 Misdiagnosed B12 Deficiency (05/18/2019)
Misdiagnosed B12 Deficiency
Vitamin B12 is needed to make the genetic material in all cells. Consequently, B12 deficiency can cause a wide range of symptoms and may be misdiagnosed as other diseases. Read about two recent cases of misdiagnosed B12 deficiency in the Cobalamin (B12) section of the B Vitamin Supplements Review. Also see our Top Picks for B12.
 B12 Tablet vs. Injection (01/15/2019)
B12 Tablet vs. Injection
Is a vitamin B12 tablet just as good as an injection for raising blood levels of B12? Find out in the Cobalamin (B12) section of the B Vitamin Supplements Review. Also see our Top Pick for vitamin B12.
 B Vitamins & Breast Cancer (01/08/2019)
B Vitamins & Breast Cancer
A reduced risk of breast cancer was associated with supplementing with certain amounts of folic acid and vitamin B12 for women predisposed to breast cancer in a new study. See the details in the "Breast cancer" section of the B Vitamin Supplements Review.
2018 B Vitamin Cancer Risk? (10/24/2018)
B Vitamin Cancer Risk?
Giving high-dose vitamin B12 along with a modest amount of folic acid to older people was found to significantly increase the risk of colorectal cancer. See the B12 section of the B Vitamins Review for details. (Also see our Top Picks for B12 and other B vitamins.)
 B12 Dosage (03/07/2018)
B12 Dosage
A study compared the effects of a high weekly dose of vitamin B12 versus a much lower dose given daily. Both worked equally well. Find out why and get more details about B12 dosing in the B-12 section of B Vitamin Supplements Review.
 B12 for Cognition (01/13/2018)
B12 for Cognition
Numerous studies show that getting adequate intake of B vitamins, such as B12, and, perhaps, omega-3 fatty acids from fish, may slow age-related declines in memory and cognition. But not everyone should expect a benefit, as shown in a recent study. For details, see the Memory, Cognition, and Alzheimer's Disease section of the B Vitamin Supplements Review. (Also see our Top Picks among products.)
2017 Signs of B12 Deficiency (11/26/2017)
Signs of B12 Deficiency
B12 deficiency is not uncommon, most often affecting older people. Symptoms include anemia, fatigue, tingling in the arms and legs and loss of balance -- but a recent case report highlights a lesser-known sign of B12 deficiency. Find out more, plus how much B12 you should get in the "B12" section of the B Vitamins Review >> (Also see our Top Picks for vitamin B12 and other B vitamins.)
 Best form of B12? (10/29/2017)
Best form of B12?
It’s important for many older adults and people using medications that reduce stomach acid to take a vitamin B12 supplement. Three different forms of B12 are sold. A recent study suggests that one may be better than another. Get the details in the B12 (cobalamin) section of the B Vitamin Supplements Review >> [Also see our Top Pick for B12 supplements in the Review.]
 High-Dose B Vitamins & Lung Cancer Risk (08/29/2017)
High-Dose B Vitamins & Lung Cancer Risk
A recent study found that taking high doses of vitamins B6 and B12 was associated with an increased risk of lung cancer among men, particulary among those who smoke. For details, see the "ConsumerTips" section of the B Vitamin Supplements Review >>
 B12 Can Cause Acne (06/20/2017)
B12 Can Cause Acne
Taking very large doses of vitamin B12 can cause outbreaks of acne -- even in older people, according to a recent report. Learn more in the "B12" section of the B Vitamin Supplements Review >>
 Side-Effect With B-12 (01/20/2017)
Side-Effect With B-12
Certain formulations of vitamin B-12 contain additional ingredients that can cause diarrhea and bloating in some people – particularly if taking more than one pill. An apparent case of this was reported to us this week. To help you avoid this, read the details in the "What CL Found" section of the B Vitamin Supplements Review (which includes our tests of products) >>
 Potential Risk with High B-12 (01/10/2017)
Potential Risk with High B-12
Among people who are malnourished, those with elevated vitamin B-12 levels in their blood were twice as likely to die when hospitalized as those with lower B-12 levels, according to a new study. The study authors suggest caution with inappropriate supplementation. For more details about the study, and vitamin B-12, see the B Vitamin Supplements Review >>
2015 How Vitamin B-12 Causes Acne (06/27/2015)
How Vitamin B-12 Causes Acne
Vitamin B-12 is a critical nutrient and many people, particularly those over 50, should supplement with B-12 to avoid deficiency. However, at doses higher than those used to prevent deficiency, B-12 may occasionally trigger acne. A new study appears to explain the B-12/acne connection. For details, see the "Cobalamin (B-12)" section of the B Vitamin Supplements Review >>
2014 Do B Vitamins Boost Memory? (11/16/2014)
Do B Vitamins Boost Memory?
This week, a study was reported in the media suggesting that taking vitamin B-12 and folic acid does not help with memory. But a closer look at this and related studies shows a benefit for some people. Get the details, plus our tests and comparisons of B-vitamin supplements, in the B Vitamin Supplements Review >> 
2013 B-12 Deficiency and Acid Inhibitors (12/14/2013)
B-12 Deficiency and Acid Inhibitors
A large, new study found the risk of vitamin B-12 deficiency to be significantly higher among people taking proton pump inhibitors (e.g., Prevacid, Prilosec) or H2-blockers (e.g., Pepcid, Zantac) than among those not taking these medications. The drugs reduce acid production in the stomach, but acid is needed to release B-12 from foods, so deficiency can occur. B-12 supplements can help because acid is not needed for their absorption. For details -- and our reviews of supplements with vitamin B-12 -- see the updated B Vitamin Supplements Review >>   

Other supplements which should or should not be used with these medications are discussed in the Proton Pump Inhibitors article, which is part of the extensive Drug Interactions section of our website (where you can look up interactions for other drugs you may be taking.) 

2012 Higher Vitamin Level May Slow Cognitive Decline (12/16/2012)
Higher Vitamin Level May Slow Cognitive Decline
An 8-year study of people in their 70's found that cognitive functioning (memory and other mental skills) declined faster among those with lower blood levels of vitamin B-12 compared to those with higher levels. Particularly surprising was that 40% of the people in the study fell into the lower B-12 group, many of whom had levels which would not normally define them as deficient in B-12. This and other recent studies suggest a role for vitamin B-12 in minimizing cognitive decline in older people. For details, see the updated B Vitamin Supplements Review. More >>
 B-12 and Folic Acid for Memory (01/08/2012)
B-12 and Folic Acid for Memory
Small but significant improvements in short and long-term memory were found to occur in older people (aged 60 to 74) given modest daily amounts of vitamin B-12 and folic acid. But don't expect immediate results. Improvements were seen only after 2 years of supplementation. See the update in the B Vitamins Review for the dosage used, as well as our ratings of supplements with vitamin B-12 and folic acid.
2011 B Vitamins May Help Memory (10/30/2011)
B Vitamins May Help Memory
A recently published study of individuals aged 70 years or more with mild cognitive impairment found that a daily dose of three B vitamins (folic acid, vitamin B-12, and vitamin B-6) over 2 years appeared to slow cognitive and clinical decline, particularly in those who started with elevated levels of plasma homocysteine. See the B Vitamin Product Review for details including the dosage used.  More >>

Recent Recalls and Warnings Found:
1.FTC Warns 50 More Companies for Coronavirus Claims (05/23/2020)
2.Seller of Botanical and CBD Oil Patches Warned for Coronavirus Claims (05/02/2020)
3.Seller of CoQ10, Resveratrol and More Warned for Manufacturing Violations (02/18/2020)
4.Brain Supplement Claims to Treat Brain Injuries, Alzheimer's Are Deceptive, Says FTC (11/02/2019)
5.Maker of Vitamin B12 and Multimineral Supplements Warned by FDA (07/18/2018)
6.FDA Warns Seller of Weight Control Patches (06/19/2018)

Archived Recalls and Warnings Found:
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1.Radio "Infomercials" for Cognitive and Joint Health Supplements Deceived Consumers, Says FTC (02/25/2017)
2.Energy Drink Linked to Case of Acute Hepatitis (11/04/2016)
3.Seller of Sublingual Vitamins Warned for Drug Claims (10/18/2016)
4.Maker of B-12 Energy Supplement Warned for Manufacturing Violations (06/03/2015)
5.Maker of Magnesium, Calcium, Zinc, B Vitamins and More Warned for Manufacturing Violations, Drug Claims (03/10/2015)
6.Seller of B-12, Zinc, Echinacea and More Warned for Manufacturing Violations and Drug Claims (12/12/2014)
7.Maker of Children's Vitamins, Weight Loss Supplements and More Warned for Manufacturing Violations (11/11/2014)
8.Seller of Cholesterol, Arthritis Supplements and More Warned for Drug Claims (11/06/2014)
9.Maker of Joint and Weight Products Warned for Hidden Drugs, Manufacturing Violations (09/23/2014)
10.Seller of "Nerve", "Cleanse" and Probiotic Supplements Warned for Drug Claims (09/05/2014)
11.Seller of Brain, Diabetes, Echinacea Supplements and More Warned for Drug Claims (05/30/2014)
12.Maker of Mood, Smoking Cessation Supplements and More Warned for Violations, Drug Claims (05/14/2014)
13.Nature Made Recalls Full Strength Mini Multivitamins (10/04/2013)
14.Maker of Sexual Enhancement Supplement Warned for Manufacturing Violations (08/28/2013)
15.Immune Supplement Recalled Due To Undeclared Milk (08/27/2013)
16.Fat Loss and Muscle Enhancement Supplements Found To Contain DMAA (08/01/2013)
17.Beware of Dietary Supplements With Claims To Treat Diabetes, FDA Warns (07/25/2013)
18.Seller of Vision Supplement Warned For Drug Claims (07/05/2013)
19.Seller of Cardio, Immune, Greens Supplements and More Warned For Drug Claims (06/13/2013)
20.Seller of Immune, Cholesterol, Liver and Blood Sugar Products Warned For Drug Claims (04/26/2013)
21.Cardio, Energy and Sexual Enhancement Supplement Distributor Warned For Manufacturing Violations and Drug Claims (04/18/2013)
22.Manufacturer of Heart, Multivitamin, Cranberry, and Longevity Supplements Warned For Adulteration and Drug Claims (02/13/2013)
23.Vitamin and Supplement Maker Warned For Labeling Errors, Manufacturing Violations (02/06/2013)
24.Seller of Blood Sugar, Depression and Sleep Supplements Warned For Making Drug Claims (12/26/2012)
25.FDA Warns Candy Maker Making Heart Health Claims (06/26/2006)

News Releases Found:
2020 Best Alternative Milks? ConsumerLab Tests Reveal What's Really in Plant-Based Milks (05/22/2020)
 Best and Worst Multivitamins Revealed by ConsumerLab -- Problems Found With 44% of Multis Tested (04/28/2020)
 Collagen and Magnesium Rise in Popularity, as Fish Oil and Curcumin Dip in Latest ConsumerLab Survey of Supplement Users (02/29/2020)
2019 ConsumerLab Tests Reveal Best B Vitamin Supplements -- 19% of B Vitamin Supplements Fail CL's Tests of Quality (06/25/2019)
2017 Reveals Best and Worst B Vitamin Supplements and Why Current Labels Often Mislead (02/23/2017)
2016 Helps Consumers Make Sense of the FDA's Updated Daily Values (DV) for Vitamins and Minerals (07/27/2016)
2012 Reveals How Much Caffeine is in Energy Drinks -- Also Finds Some Drinks and Dietary Supplements Don't Contain Claimed Amounts of B Vitamins (09/27/2012)
2010 reports deficiencies in some B-complex supplements and more caffeine than expected in "shot-sized" B vitamin "energy" drinks (10/26/2010)
2009 Warns of Problems with Multivitamins and Vitamin Water -- Defects Found in Over 30% of Supplements Selected for Testing; Several Popular Children's Multis Exceed Tolerable Limits (03/31/2009)
2002 finds most B vitamin supplements contain what they claim, but often exceed safe levels — Consumers cautioned to be aware of side effects with high dose products (01/08/2002)


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