Front of Nature's Bounty B-12 1000 mcg 200 coated tablets bottle

Nature's Bounty Best Value · Vitamins & Minerals

Vitamin B-12 1,000 mcg

Q: Is 1,000 mcg of B12 too much?

For most people it is safe. The adult RDA is 2.4 mcg, but only about 1.3% of a 1,000 mcg oral dose is absorbed, and no upper limit has been set because of B12's low toxicity. NIH does note one observational study linking long-term use of 55 mcg or more a day with higher lung cancer risk in men, so take high doses when there is a reason to.

Q: Is cyanocobalamin worse than methylcobalamin?

Not in any way that matters for most people. Cyanocobalamin is converted in the body to the active forms methylcobalamin and adenosylcobalamin, and NIH's Office of Dietary Supplements says there is no evidence that absorption of supplemental B12 varies by form. It is also the most common form used in supplements, which helps keep this product inexpensive.

Q: Who is most likely to benefit from a B12 supplement?

People at higher risk of low B12: older adults (NIH cites deficiency rates of 3% to 43% among community-dwelling older adults, especially those with atrophic gastritis), people who eat few or no animal foods, and people taking metformin or acid-reducing medications. Fatigue has many causes, so a blood test is the best way to confirm you need it.

A best-selling 1,000 mcg cyanocobalamin tablet at about 5 cents a day; small and easy to swallow, with no third-party seal.

8.5

Excellent

Nutrition Reviews score

Weighted across efficacy, quality, value, experience & transparency. See breakdown

Form: Tablet
Serving: 1 tablet
Servings: 200
Videos: 1

VegetarianGluten-freeNon-GMOSoy-freeDairy-freeSugar-free

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Last reviewed September 29, 2026 by the Nutrition Reviews Editorial Team · How we review

Our verdict

For most people who need extra B12, this is the simplest and cheapest effective option: a well-studied form at a dose that compensates for limited absorption, in a tablet anyone can swallow. It lacks independent certification and its listings are sloppy, but the formula itself is sound.

Best for

Adults over 50 and others at higher risk of low B12
People who eat few or no animal foods
Budget shoppers

Skip it if

Anyone who wants third-party certified supplements
People who want a combined B-complex

How it scored

Our five-factor score out of 10. Factors are weighted by how much they matter to the outcome you’re paying for. Methodology

8.5

Excellent

out of 10

Efficacy30%8.8
Key ingredients at clinically studied doses, and how strong the evidence is.
Quality & Purity25%7.2
Third-party testing and certifications, manufacturing standards, contaminant testing, recall history.
Value20%9.8
Cost per effective serving compared with category peers.
Experience15%9.0
Taste, mixability, texture and tolerability from aggregated buyer and creator feedback.
Transparency10%7.5
Full label disclosure (no proprietary blends), available COAs, honest marketing.

Our review

Nature's Bounty Vitamin B-12 1,000 mcg is one of Amazon's best-selling B12 supplements, with nearly 78,000 ratings and more than 40,000 bottles bought in a recent month, and it is about as inexpensive as supplements get: $9.97 for 200 small coated tablets, or around 5 cents a day. Each tablet contains 1,000 mcg of vitamin B12 as cyanocobalamin in a simple base of dicalcium phosphate, cellulose and stearic acid, and it is labeled non-GMO, gluten-free and suitable for vegetarians.

Cyanocobalamin is the most common form of B12 in supplements and is converted in the body to the active forms methylcobalamin and adenosylcobalamin. NIH notes there is no evidence that absorption of supplemental B12 differs by form, so methyl-B12 marketing on pricier products is not a reason for most people to pay more.

The dose looks enormous next to the 2.4 mcg adult RDA (41,667% of the Daily Value), but that is by design. Only a small share of a large oral dose is absorbed, about 1.3% at 1,000 mcg according to NIH, and B12 has no upper intake limit because of its low potential for toxicity. That makes a daily 1,000 mcg tablet practical for people at higher risk of low B12, including older adults, people who eat few animal foods, and people taking metformin or acid-reducing drugs.

The caveats are about oversight rather than the formula. The product carries no USP or NSF certification, relying on Nature's Bounty's own GMP and in-process testing, the brand's website still shows an outdated 16,667% Daily Value, and the Amazon listing's directions mistakenly refer to melatonin. Video reviewers describe the round tablets as small and easy to swallow.

What’s inside

Key ingredient	Per serving	Why it matters
Vitamin B12 (as cyanocobalamin) 41,667% DV; about 1.3% of a 1,000 mcg oral dose is absorbed, and B12 has no upper limit.	1,000 mcg	41,667% DV; about 1.3% of a 1,000 mcg oral dose is absorbed, and B12 has no upper limit.

Supplement Facts

Serving Size 1 Tablet

Amount Per Serving% Daily Value

Vitamin B-12 (as Cyanocobalamin) 1,000 mcg41,667%

* Percent Daily Values are based on a 2,000 calorie diet. † Daily Value not established.

Other ingredients: Dicalcium phosphate, vegetable cellulose, vegetable stearic acid. Contains <2% of: Silica, vegetable magnesium stearate.

Transcribed from the manufacturer’s label (vitacost.com). Formulas change — always check the label on the product you buy.

Testing & quality

Nature's Bounty says products follow GMP standards and undergo quality tests and assays throughout manufacturing; its B-12 1,000 mcg tablets carry no USP or NSF certification.

Goals it supports

Energy General Wellness Healthy Aging

Creator video reviews

Independent creators reviewing Vitamin B-12 1,000 mcg on TikTok and YouTube.

1 positive0 mixed0 critical

Pros & cons

What we like

About $0.05 per day
1,000 mcg dose compensates for limited absorption of oral B12
Small, coated tablets that are easy to swallow
Non-GMO, gluten-free and suitable for vegetarians

Watch-outs

No USP or NSF certification
Brand site shows an outdated %DV and the Amazon listing has copy errors
Far more B12 than people with normal levels need

Questions buyers ask

Is 1,000 mcg of B12 too much?

For most people it is safe. The adult RDA is 2.4 mcg, but only about 1.3% of a 1,000 mcg oral dose is absorbed, and no upper limit has been set because of B12's low toxicity. NIH does note one observational study linking long-term use of 55 mcg or more a day with higher lung cancer risk in men, so take high doses when there is a reason to.

Is cyanocobalamin worse than methylcobalamin?

Not in any way that matters for most people. Cyanocobalamin is converted in the body to the active forms methylcobalamin and adenosylcobalamin, and NIH's Office of Dietary Supplements says there is no evidence that absorption of supplemental B12 varies by form. It is also the most common form used in supplements, which helps keep this product inexpensive.

Who is most likely to benefit from a B12 supplement?

People at higher risk of low B12: older adults (NIH cites deficiency rates of 3% to 43% among community-dwelling older adults, especially those with atrophic gastritis), people who eat few or no animal foods, and people taking metformin or acid-reducing medications. Fatigue has many causes, so a blood test is the best way to confirm you need it.

Sources we checked (6)

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