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Sublingual B-12 vs. Vitamin B-12 Pills -- B-12 supplements


Although sublingual B-12 — a form placed under the tongue and allowed to dissolve — is often promoted for better absorption, there does not appear to be much evidence for this. In fact, one clinical study comparing the same amount of B-12 given orally or under the tongue found they were equally effective at correcting B-12 deficiency over a two-month period.

Be aware that sublingual B-12 supplements often contain sugar substitutes such as sorbitol, mannitol or sucralose, which can cause gastrointestinal symptoms in some people.

It should also be noted that unlike the vitamin B-12 in foods, the purified form of B-12 found in supplements, including regular and sublingual tablets, does not require stomach acid for it to be made available for absorption. This benefits people with low stomach acid (including many people over the age of 50) or those who take acid blockers such as Pepcid or Zantac, or proton pump inhibitors such as Prevacid, or Prilosec, who are at an increased risk for B-12 deficiency. For those who have difficulty with large pills, keep in mind that only a very small amount of B-12 is required to meet the recommended daily intake and can be obtained in small tablets, including those tested by in its B Vitamins Supplements Review, which includes our Top Pick for vitamin B-12 and the latest information about B-12 dosage and safety and when to take vitamin B-12.

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harold jitschak15237
July 2, 2017

When starting in Israel in 1979 I saw -after a few patients with aphthous ulcers got quickly better from B12 i.m [injections][published I think in the seventies in the BMJ? B12/folic acid and iron]] thereafter tens of patients with the same problem. They all reacted-with a rare exception on B12, which I did not even expect
Every now and then [3-6 months?] they needed a b12 shot to keep the ulcers away.
When sublingual B12 from Solgar became available [as cobalamine] in Israel I switched all these patients to this.
Virtually all the patient came quickly back as it did not seem to help them.
I went back to the injections!
The injectable B12 in Israel was[and is still] only available as cyanocobalamine.
For years I have treated tenfold [or hundreds] of patients this way, as well as many chronic tired patients [with normal b12 levels] which I learned as being non-sense in medical school [but every practitioner can tell you about this "placebo" effect[but no other placebos worked!]
After b12 came available as sublingual methylcobalamine it became clear to me that there is a huge difference and that simple cobalamine tablets are a waste of money.
The methylcobalamine worked for all these patients.
I do realize that the literature is full of disproving this but I would have to be an idiot to ignore my more then 25 years experience.
How much in the literature has been copied just one from the other?? I am curious.
Why not collect experience data from older practitioners instead of just copying some [double blind] studies?
If one has no financial or other interest in an issue I think first of all one has to believe his own experience if this very clear.

July 5, 2017

Thank you Harold Jitschak15237. I agree 100% and I'm not a physician. However, I have personal experience. I was forced to become knowledgeable and be a patient advocate for my dying mother. She has had fibromyalgia (severe muscle pain and migraines) for 30 years. For years her doctor gave her a monthly shot of B12 (cyanocobalamin form). Within a week of switching her to the B12 methylcobalamin her pain started easing and she had energy; prior she was bedridden. It's been 2 years and she's a new person, living everyday with energy and no migraines. We've make other changes like getting her off most of her prescription medications and adding essential supplements like D3, K2-MK7, Magnesium, probiotics,New Chapter Wild Alaskan fish oil, etc, but the 1 biggest difference that practically happened overnight was changing her B12 form to methlycolbalamin. It was changed my life as well. There's probably other good brands, but we take Neuro Biologix Methylation Complete, because this is the one recommended by my Intergrative MD. It's a sublingual; anyone over 50 can't absorb B12 well from a pill. Bottle says 2 a day, but blood work reveals only 1 a day gets us in the high optimal range. Hope this helps others.

March 15, 2019

Thanks Harold for sharing your valuable knowledge from clinical experience! I am wondering about the chronic fatigue patients with "normal" B12 levels. Was the testing method inaccurate? I know this is an issue with many nutrients (magnesium is an example); the testing methods are not accurate. The doctor says "it's normal", yet it is not being ABSORBED or used by the body. What is the best way to measure B12? Perhaps the homocysteine level may be a proxy? (Those with high Hcy may have a genetic mutation that makes it difficult to process/ convert cyanocobalamin to the usable form methylcobalamin).

January 3, 2016

I'm looking for information on the safety of B-12 patches. They are not listed in the B-12 reviews. Are they safe? Are they effective?
March 31, 2016

Hi Stacie - There is one very small experiment (described in a patent for a vitamin B-12 patch ) in which four people wore vitamin B-12 patches over an 8 hour period, at the end of which vitamin B-12 levels in the blood were reported to have doubled ( However, there do not appear to be any published, controlled clinical studies demonstrating whether these patches are safe and effective, or comparing the use of these patches to oral B-12 supplementation.

September 9, 2015

Replacement B-12 for gastric disease or or dietary deficiency is one thing. But when a person needs pharmacologic doses of B-12 along with folate and B-6 to lower dangerous levels of homocysteine, the recommended dietary allowances do not apply. There should not be a single interpretation for B-12 requirements based on correcting deficiencies. B-12 absorption required for administration of higher amounts of B-12 in people with homocysteine elevation must be considered separately. I would like to see if oral lozenges are better in that other circumstance.

More generally, I would like to see devote more attention than it does currently to nutrient administration at pharmacological levels to reduce known high risk factors than merely to minimal maintenance requirements in otherwise normal people.
September 10, 2015

Hi William - As you note, the recommended daily allowance applies only to maintaining adequate levels of vitamins and minerals, not treating deficiency. Higher amounts are required to treat deficiency, and this is clearly noted in our Reviews. Regarding your interest in lozenges, there does not seem to be any evidence suggesting that these would be a better way to take B vitamins.

September 10, 2015

Thank you. My main interest in making that comment, though, was not in treating deficiencies but in the use of some of the metabolic functions of these nutrients at super "normal" levels to treat other diseases or to prevent diseases not normally associated with a deficiency of that nutrient. An example would be vitamin D3, which has a very low minimal requirement for bone health, but which requires sometimes ten times as much to achieve its effects at improving insulin sensitivity in diabetes or pre-diabetes or its published positive effects on brain function. This is what I was referring to with regard to B-12 lowering high levels of artery-damaging blood homocysteine levels. This might require several times more B-12 than is needed to correct deficiencies. This is not to argue a point with your answer, which was fine. It is merely to request additional mention of these things in your answers.
September 10, 2015

There are some situations in which very high doses of nutrients are given. For example, high-dose niacin can lower cholesterol. High-dose fish oil can lower triglycerides. These are discussed in the relevant Reviews in the "What It Does" section. There are also potential side-effects/adverse effects when using high doses, and those are noted in the "Concerns and Cautions" sections. One needs to be very careful when using high doses -- there are pros and cons. Anything that has an effect probably has a side-effect.

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