To get the best B vitamin complex, you need to focus on two things: getting the specific B vitamins you're most likely to need, and not taking potentially harmful amounts of any them. In ConsumerLab.com's latest B Vitamin Supplements Review
, we identify our current Top Pick
, which accomplishes these goals, is inexpensive, and has been shown in our independent tests to provide its listed ingredients and properly break apart to release those ingredients.
Although you need a laboratory to know what's truly in a supplement and if it's made properly, you can use the following information to judge B-complexes:
What you absolutely want:
The B vitamin older people are most likely to need is vitamin B-12 because absorption of B-12 from foods can decrease with age, while B-12 from supplements is easier to absorb. The recommended intake of B-12 is quite small — just 2.4 mcg per day. While B-12 is quite safe and there is no established upper intake limit, people with diabetes or kidney disease should stay under 1,000 mcg or 1 mg per day.
Althogh it's easy to get enough B-6 from your diet, mild deficiency is common, particularly in the elderly and children. You need 1.3 mg (under age 51), 1.7 mg (men 51+), and 1.5 mg (women 51+). However, there is an upper tolerable intake limit of 100 mg, which some B-complexes exceed and you should avoid.
What to watch out for:
Other B vitamins you should get from a B-complex but have upper limits are:
You need 400 mcg daily. The upper limit is 1,000 mcg, but be aware that synthetic forms count as 170% of the listed amount. This means that a supplement with more than 588 mcg of folic acid or methylfolate, exceeds the tolerable daily intake limit
. In addition, most Americans and Canadians get enough folate from their diet because of fortification of enriched flour with folic acid. Stick with a product that provides no more than 400 mcg from folic acid or other synthetic folate.
You need 16 mg (men) or 14 mg (women): Many B-complexes exceed the upper tolerable intake limit which is 35 mg.
It is rare to be deficient in the other B vitamins if you are relatively well-nourished, but it's fine to get the daily requirements from a B-complex and no upper limits have been established for these. They, and their daily requirements, are: thiamin (B1)
: 1.2 mg (men) and 1.1 mg (women); riboflavin (B-2)
: 1.3 mg (men), 1.1 mg (women); pantothenic acid (B-5)
: 5 mg, and biotin (B-7)
: 30 mcg.
More information about each of these B vitamins, their different forms, what they do, and potential concerns are found in the B Vitamin Supplements Review
Learn More About Vitamin B Complex
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Can taking too much vitamin B-6 be dangerous? The label on my multivitamin states it contains 2000% the Daily Value! >>
Can taking too much vitamin B-12 be dangerous? The label on my B-complex states it contains 50,000% the Daily Value! >>
I have been having neurological symptoms, and a blood test showed I have toxic levels of vitamin B-6. My multivitamin contains 75 mg of B-6, but this is below the upper limit of 100 mg per day. Could my vitamin contain more than it lists? >>
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? >>
This CL Answer initially posted on 4/26/2017.
Last updated 7/25/2017.