6 min. read
Journal · Energy & vitality
On a vegan or vegetarian diet, B12 is not just one supplement among others. It is the supplement not to forget: energy, the nervous system and homocysteine metabolism depend on it.
Vitamin B12 (cobalamin) is produced exclusively by micro-organisms: bacteria and archaea. It then accumulates in animal tissues: meat, fish, eggs, dairy products. Plants contain almost none. And what some algae (spirulina, nori) appear to contain are inactive analogues, with no useful metabolic effect, which can even mask a deficiency.
This means that on a strict vegetarian or vegan diet, B12 supplementation is not optional. It is a physiological necessity. Health bodies around the world, the WHO, ANSES and the Academy of Nutrition and Dietetics, confirm it unambiguously: any diet that excludes animal products must be supplemented with B12, systematically and for life.
Its role in the body is fundamental. It is involved in energy metabolism (ATP production in the mitochondria, via methionine synthase and methylmalonyl-CoA mutase), in the synthesis of neurotransmitters (dopamine, serotonin), in the formation of myelin, the protective sheath around nerves, and in the regulation of homocysteine, a marker monitored in cardiology and neurology.
Scientific study
How prevalent is vitamin B12 deficiency among vegetarians?
This reference review establishes that 92% of non-supplemented vegans are deficient in B12, compared with 47% of lacto-ovo vegetarians. Even among those who eat dairy products and eggs, half remain insufficient: the bioavailability of B12 in these foods is low and intake is often too low.
What this means in practice: anyone on a vegetarian or vegan diet should take a B12 supplement, however long they have followed the diet and however healthy they feel.
“On a vegan diet, B12 is not a comfort supplement. It is a nutrient the body needs and that the diet cannot provide.”
What is specific about B12 deficiency is how slowly it develops. The body stores B12 in the liver, and these reserves can cover 2 to 5 years of needs, sometimes more. Someone who has recently gone vegan may therefore feel no symptoms for years, while their reserves gradually run down.
The signs described in the literature when status becomes low are not very specific: persistent fatigue with no apparent cause, tingling in the hands and feet, brain fog, memory lapses, mood changes. These signs call for a medical diagnosis: only a healthcare professional and a blood test can link them to B12 status. A food supplement replaces neither this advice nor medical care.
The other point to watch is absorption. Dietary B12 depends on a complex mechanism involving intrinsic factor, a stomach protein whose secretion decreases with age and with certain medicines. Nearly 50% of people over 50 absorb B12 poorly even when they eat it. The sublingual route, for its part, does not depend on intrinsic factor.
B12 Cell Boost was formulated to meet the three challenges of B12 supplementation: absorption, cellular activation and duration of action. The solution is a three-form sublingual spray: three cobalamins with complementary profiles, absorbed directly under the tongue, without passing through the gastric barrier or depending on intrinsic factor.
This is a point that matters for vegans: unlike capsules or tablets, the sublingual route does not depend on the state of the digestive lining, a mechanism of interest for people whose intestinal absorption is reduced.
The formula is 100% vegan, with no ingredients of animal origin. The yuzu flavour makes it pleasant to take and easy to remember. A 20 ml bottle contains 133 sprays, more than a month at the full dose.
| Form | Role |
|---|---|
| Methylcobalamin | Directly active form, cofactor of methionine synthase. Involved in the methylation cycle (homocysteine metabolism), neurotransmitter synthesis pathways and the maintenance of myelin. Fast kinetics: tissue peak described at 1 hour. |
| Hydroxocobalamin | Storage form with high tissue affinity. Released gradually over 16 to 24 hours and converted into methyl- and adenosylcobalamin as needed. Helps maintain liver reserves over time. |
| Cyanocobalamin | Reference form, very stable, converted into active forms according to metabolic needs. Provides a regular, predictable baseline intake. Works together with the other two forms for complete coverage: immediate absorption, storage and prolonged activation. |
Details of the ingredients and patented forms used in our formulas are documented in the Active ingredients blog.
The sublingual spray is the simplest format there is for taking B12: no tablet to swallow, no dose to calculate, no glass of water. Just one rule to remember: 4 sprays in the morning, under the tongue.
About the dose. Sublingual absorption of B12 is partial: about 1 to 3% of the dose passes directly through the lining of the mouth. The rest, swallowed, is absorbed by the digestive system less efficiently. A high dose guarantees a sufficient effective intake, even when individual absorption varies.
“4 sprays under the tongue in the morning. That is all it takes never to run short of B12 again.”
The effects of B12 supplementation vary with the initial level of deficiency. People with a marked deficiency often report a clear improvement in energy and mental clarity from the 2nd or 3rd week. Those who supplement without a confirmed deficiency maintain their reserves and support the normal functioning of their nervous system over time.
Precautions. Food supplements should not be used as a substitute for a varied and balanced diet and a healthy lifestyle. If you are pregnant, breastfeeding or taking medication, consult a healthcare professional. Contains potassium sorbate and sodium benzoate (preservatives). Keep out of reach of children.
Yes, systematically and for life. B12 is produced by micro-organisms and is found almost only in animal products; 92% of non-supplemented vegans are deficient, compared with 47% of lacto-ovo vegetarians. Algae such as spirulina only provide inactive analogues.
No. Sublingual absorption is partial (about 1 to 3% of the dose passes directly through the lining of the mouth), which justifies a high dose to guarantee an effective intake. B12 is water-soluble and any excess is eliminated in the urine: the 39,280% of NRV presents no risk, as the NRV (2.4 µg/day) is a physiological minimum and not a ceiling.
Take your 4 sprays when you remember, at midday or even in the afternoon. Daily regularity matters more than the exact time; if you miss a whole day, simply start again the next day at the normal dose, without doubling up.
On a vegan or vegetarian diet, supplementation is permanent, not cyclical. The 1 to 2 month course suits non-vegans correcting a temporary deficiency; vegans simply order a new bottle when the previous one is finished.
Yes, with no known contraindication. B12 Cell Boost combines well with Magnesium Active+, a coenzyme in many B12-dependent reactions, and with a vitamin B complex such as Energy Daily Flow (B6, folate) to support the methylation cycle. More analyses are published in the BIOLOGYST Journal.
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