The overlooked minerals in caviar: B12, selenium, and iron
Protein and omega-3 get most of the attention when people talk about caviar nutrition. The minerals tend to go unmentioned — which is strange, because they're arguably the more distinctive story.
A 30g serving of sturgeon caviar is a significant source of vitamin B12, a meaningful source of selenium, and a modest source of iron. Here are the numbers, the context, and where caviar sits relative to other whole-food sources of each.
Vitamin B12: the standout number
A 30g serving of sturgeon caviar contains approximately 3.5 micrograms of vitamin B12 — roughly 150% of the US adult daily reference amount. This is the single most significant micronutrient in caviar by percentage of daily intake.
B12 is one of a small number of nutrients the human body cannot synthesise on its own. It must come from food, and the richest natural sources are all animal-derived — fish, shellfish, liver, eggs, dairy. B12 helps maintain normal red blood cell formation and normal neurological function.
How does caviar compare to other whole-food sources of B12? By weight:
| Food | B12 per 100g | % Daily Value |
|---|---|---|
| Beef liver | ~70 mcg | ~2,900% |
| Clams | ~49 mcg | ~2,050% |
| Sturgeon caviar | ~12 mcg | ~500% |
| Sardines | ~9 mcg | ~375% |
| Mackerel | ~8 mcg | ~335% |
| Salmon | ~3 mcg | ~125% |
| Eggs | ~0.9 mcg | ~38% |
| Whole milk | ~0.5 mcg | ~20% |
Per gram, caviar is denser in B12 than most fish, ahead of eggs and dairy, and behind only the most extreme liver and shellfish sources. One small tin provides well over a day's intake.
Selenium: the mineral most people don't think about
A 30g serving of sturgeon caviar provides approximately 20 micrograms of selenium — about 35% of the daily reference amount. Selenium is a trace mineral that functions as a cofactor in several enzyme systems.
The dietary sources of selenium are unusual — Brazil nuts are the most extreme (a single nut can exceed a daily intake), followed by seafood and organ meats. Caviar sits comfortably in the upper range of common foods:
| Food | Selenium per 100g | % Daily Value |
|---|---|---|
| Brazil nuts | ~1,917 mcg | ~3,485% |
| Tuna | ~108 mcg | ~196% |
| Sturgeon caviar | ~65 mcg | ~118% |
| Sardines | ~52 mcg | ~95% |
| Chicken breast | ~27 mcg | ~49% |
| Eggs | ~31 mcg | ~56% |
| Brown rice | ~20 mcg | ~36% |
Per 100g, caviar sits between tuna and sardines — in the meaningful-selenium bracket for whole foods, well clear of the general average.
Iron: modest, but heme
A 30g serving of sturgeon caviar contains approximately 2 mg of iron — about 11% of the daily reference. The percentage isn't remarkable in isolation, but the form matters.
Iron in caviar is heme iron — the type found in animal products. Heme iron is absorbed more efficiently than the non-heme form found in plant sources. The practical result is that a given milligram of iron from caviar (or meat, or fish) contributes more to iron status than the same milligram from spinach or lentils. Iron is used by the body to transport oxygen in the blood.
This doesn't make caviar a serious iron source — you'd have to eat 100g+ to hit a third of daily intake. But it's worth mentioning as part of the nutritional profile rather than leaving out.
The other mentioned minerals
Smaller but non-zero amounts of several other minerals appear per 30g:
- Phosphorus — ~110 mg, around 9% DV. Structural component of bone and teeth, involved in energy metabolism.
- Magnesium — ~9 mg, around 2% DV. Small contribution.
- Vitamin D — ~24 IU, around 3% DV. Not a significant source; sunlight and fortified foods do more.
- Zinc — ~0.3 mg, around 3% DV. Trace contribution.
None of these numbers is independently remarkable, but they round out the nutritional picture.
What to take from this
Three observations worth taking away.
First, the B12 density is the standout. A single 30g tin provides more than a full day's reference intake of a nutrient many people under-consume — particularly those reducing meat and dairy for other reasons.
Second, selenium at 35% DV per serving is meaningful. Most people aren't tracking their selenium intake, but if you're paying attention to it, caviar is a dense source.
Third, none of this is the reason to buy caviar. People eat it for the experience — the pearls, the pop, the salinity, the ritual. The nutritional profile is context for a food that makes sense on its own terms. If you're going to eat it, knowing what's in it is useful. That's all.
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Nutritional values are approximate and vary by species, lot, and serving size. Refer to each product's nutrition facts panel for verified amounts. This content is editorial. Just Caviar products are conventional foods, not dietary supplements, and are not intended to diagnose, treat, cure, or prevent any disease.