Vitamin B12
Vitamin B12 comes almost exclusively from animal products in our database: liver at 70 µg per 100 grams, mackerel at 19 µg, oysters at 16 µg and smoked herring at 13.7 µg. The European reference intake is 2.5 µg per day (EU NRV). Not one plant source appears on the list.
The authorised wordings
Regulation (EU) No 432/2012 lists for this vitamin, among others: "vitamin B12 contributes to normal red blood cell formation", "vitamin B12 contributes to normal energy-yielding metabolism" and "vitamin B12 contributes to the normal function of the immune system". A great deal gets promised around B12 in the market on energy and concentration. The permitted sentence concerns a normal metabolism, not extra energy, and we hold that distinction carefully.
Four sources that tower over the rest
Per 100 grams: liver 70 µg, mackerel 19 µg, oysters 16 µg, smoked herring 13.7 µg and raw mussels 12 µg. Crab follows at 9 µg. Set that against a reference intake of 2.5 µg and the picture is clear: one serving of oily fish a week already covers what a week needs. Meat, dairy and eggs deliver smaller amounts, but they do it daily and across several meals.
2.5 µg a day, and how absorption works
The EU NRV sits at 2.5 µg per day. What makes this vitamin unusual is that absorption runs through a protein in the stomach and is therefore limited per intake; large amounts at once are not fully used. At the same time the liver holds a reserve that lasts a long while. Those two properties together explain why a change in diet only shows up in a blood value after a considerable delay.
Plant-based eating and this vitamin
Our database holds no plant source with a B12 value, and that is not an omission: in nature the vitamin occurs practically only in animal products. The Netherlands Nutrition Centre therefore advises people eating fully plant-based to supplement vitamin B12. That is their position, not our sales pitch — we sell no supplements. For how to arrange it and how to check your values, your GP is the right address.
What we do and do not do here
At intake we always ask whether someone eats animal products and whether a supplement is already in use, because the answer shapes the rest of the nutrition plan. What we do not do is prescribe a dose or name a brand; that belongs with a doctor, not a coach. We do build the weekly menu so oily fish has a fixed place in it, because that settles iodine and omega-3 alongside this vitamin.
How we compile this list
We sort every row in the DCRAFT food database on the measured value per 100 grams and take the top of that list. Rows recorded per piece, per slice or per portion do not count, because a value per piece cannot be compared with a value per 100 grams. Products listed under a brand name are left out: their composition changes outside our control, and a ranking resting on it ages without us noticing. Where several products carry precisely the same value, it comes from one shared row in our source data and we name one product from that group. We set this rule out here because a ranking without a visible selection rule is an opinion rather than a measurement.
Frequently asked questions
Which foods contain the most vitamin B12?
Liver leads at 70 µg per 100 grams, trailed by mackerel at 19 µg and oysters at 16 µg. Every strong source in our database is animal-derived.
How much vitamin B12 do you need per day?
The EU NRV sets the daily value at 2.5 µg. A single serving of mackerel already supplies a multiple of that.
Do plant foods contain vitamin B12?
No plant source in our database carries a B12 value. Fortified products are the exception, but that fortification is printed on the label rather than present in the natural composition.
Can you be low in vitamin B12?
That is not something you infer from a food table. The liver reserve makes the picture slow; only blood work through your GP settles it.
Sources
- DCRAFT food database — KILLER COACH ENGINE V2.3 workbook (accessed 26 August 2026)
- EU NRV — Regulation (EU) No 1169/2011, Annex XIII (accessed 26 August 2026)
- Regulation (EU) No 432/2012 (accessed 26 August 2026)
- Netherlands Nutrition Centre (accessed 26 August 2026)
Please note: This is general information about nutrition, not medical advice. If you have symptoms or suspect a deficiency, discuss it with your doctor. We do not sell supplements and have no commercial interest in any brand.
Last updated: .
Written by Dennis, founder of Dcraft Of Fitness.