Cobalt
What it is and what it does
- WHO counts cobalt as an essential element in the form of vitamin B12. (WHO (1996). Trace elements in human nutrition and health. Prepared in collaboration with FAO and IAEA. Geneva: World Health Organization)
- Vitamin B12 contains the mineral cobalt, which is why compounds with vitamin B12 activity are called cobalamins. (NIH Office of Dietary Supplements. Vitamin B12 Fact Sheet for Health Professionals (updated 2025-07-02))
- ICMR-NIN lists cobalt among the micro minerals. (ICMR-NIN. Dietary Guidelines for Indians 2024)
- The main function of cobalt in humans comes from its role in vitamin B12 (cobalamin). (Genchi G, Lauria G, Catalano A, Carocci A, Sinicropi MS (2023). Prevalence of Cobalt in the Environment and Its Role in Biological Processes. Biology (Basel) 12(10):1335 (DOI 10.3390/biology12101335))
- Mammals, including humans, cannot make vitamin B12 themselves; some bacteria and archaea can. (Genchi G, Lauria G, Catalano A, Carocci A, Sinicropi MS (2023). Prevalence of Cobalt in the Environment and Its Role in Biological Processes. Biology (Basel) 12(10):1335 (DOI 10.3390/biology12101335))
- Vitamin B12 is required for the development, myelination and function of the central nervous system. (NIH Office of Dietary Supplements. Vitamin B12 Fact Sheet for Health Professionals (updated 2025-07-02))
- Vitamin B12 is a cofactor for two enzymes, methionine synthase and L-methylmalonyl-CoA mutase. (NIH Office of Dietary Supplements. Vitamin B12 Fact Sheet for Health Professionals (updated 2025-07-02))
Why it matters
- Vitamin B12 deficiency can cause fatigue, nerve changes and megaloblastic anaemia, among other symptoms. (NIH Office of Dietary Supplements. Vitamin B12 Fact Sheet for Health Professionals (updated 2025-07-02))
- ICMR-NIN names vitamin B12 as a nutrient of concern for vegetarians: getting enough is a challenge. (ICMR-NIN. Dietary Guidelines for Indians 2024)
- Vegetarians and vegans are at higher risk of vitamin B12 deficiency, because this vitamin is not available from plant sources. (Genchi G, Lauria G, Catalano A, Carocci A, Sinicropi MS (2023). Prevalence of Cobalt in the Environment and Its Role in Biological Processes. Biology (Basel) 12(10):1335 (DOI 10.3390/biology12101335))
- Vitamin B12 has no upper limit, because of its low potential for toxicity. (NIH Office of Dietary Supplements. Vitamin B12 Fact Sheet for Health Professionals (updated 2025-07-02))
- Too much cobalt itself (in high concentrations) may cause vomiting, nausea, diarrhoea, bleeding, low blood pressure, heart disease and thyroid damage. (Genchi G, Lauria G, Catalano A, Carocci A, Sinicropi MS (2023). Prevalence of Cobalt in the Environment and Its Role in Biological Processes. Biology (Basel) 12(10):1335 (DOI 10.3390/biology12101335))
General information, not medical advice — for your own needs, ask a doctor or dietitian.
How much is needed
| Who | Amount | What the figure is | Whose figure |
|---|---|---|---|
| India, all groups | no value set | No ICMR-NIN 2020 value | ICMR-NIN 2020 |
| Adults, as vitamin B12 (men and women) | 2.2 ug/day | RDA (vitamin B12) | ICMR-NIN 2020 |
| Pregnant woman, as vitamin B12 (additional) | +0.25 ug/day | RDA (vitamin B12) | ICMR-NIN 2020 |
| Lactating woman, as vitamin B12 (additional) | +1.0 ug/day | RDA (vitamin B12) | ICMR-NIN 2020 |
| Adults, as vitamin B12 (text) | RDA 2.2 ug/day | RDA (vitamin B12) | ICMR-NIN 2020 |
| Adults 19+ years, as vitamin B12 (US) | 2.4 ug/day vitamin B12 | RDA (as vitamin B12; not a cobalt value) | US NASEM via NIH ODS (not an Indian value); a vitamin B12 value, not a cobalt value |
| Pregnancy / breastfeeding, as vitamin B12 (US) | 2.6 / 2.8 ug/day vitamin B12 | RDA (as vitamin B12; not a cobalt value) | US NASEM via NIH ODS (not an Indian value); a vitamin B12 value, not a cobalt value |
| Cobalt inside the adult B12 RDA | 0.1 ug cobalt/day | Cobalt contained in 2.4 ug vitamin B12 (not an official cobalt requirement) | Peer-reviewed review (Genchi et al. 2023), derived from the US B12 RDA; not an official or Indian value |
| Adults (US) | no value set | UL for vitamin B12 | US NASEM via NIH ODS (not an Indian value) |
India’s own figure (ICMR-NIN 2020) comes first. Figures from other bodies are shown only where they help, and say whose they are.
Sources: ICMR-NIN Expert Group. Short Report of Nutrient Requirements for Indians: Recommended Dietary Allowances and Estimated Average Requirements - 2020; NIH Office of Dietary Supplements. Vitamin B12 Fact Sheet for Health Professionals (updated 2025-07-02); Genchi G, Lauria G, Catalano A, Carocci A, Sinicropi MS (2023). Prevalence of Cobalt in the Environment and Its Role in Biological Processes. Biology (Basel) 12(10):1335 (DOI 10.3390/biology12101335)
In every millet and pseudo-cereal, per 100 g raw
| Grain | Amount | Source |
|---|---|---|
| Bajra (pearl millet) | 0.03 mg | IFCT A003 |
| Ragi (finger millet) | 0.022 mg | IFCT A010 |
| Rajgira (amaranth) | 0.021 mg | IFCT A002 |
| Jowar (sorghum) | 0.012 mg | IFCT A005 |
| Kodo millet | 0.005 mg | IFCT A017 |
| Little millet | 0.001 mg | IFCT A016 |
Each grain has ONE source, named on its page: IFCT = Indian Food Composition Tables 2017 (ICMR-NIN) with its food code; USDA FDC; FAO WAFCT 2019; NIN 2007 via ICAR-IIMR. Values exactly as printed, not converted — tables differ in method, so compare within a source. Published values for the grain, not a laboratory test of our packs.
Absorption and food
- Vitamin B12 in food is bound to protein and must be released before it is absorbed. (NIH Office of Dietary Supplements. Vitamin B12 Fact Sheet for Health Professionals (updated 2025-07-02))
- In fortified foods and supplements, vitamin B12 is already in free form and does not need this release step. (NIH Office of Dietary Supplements. Vitamin B12 Fact Sheet for Health Professionals (updated 2025-07-02))
- Dietary cobalt intake is about 5-50 ug a day, most of it in inorganic form. (Genchi G, Lauria G, Catalano A, Carocci A, Sinicropi MS (2023). Prevalence of Cobalt in the Environment and Its Role in Biological Processes. Biology (Basel) 12(10):1335 (DOI 10.3390/biology12101335))
- Vitamin B12 is only a small fraction of the cobalt people take in by mouth. (Genchi G, Lauria G, Catalano A, Carocci A, Sinicropi MS (2023). Prevalence of Cobalt in the Environment and Its Role in Biological Processes. Biology (Basel) 12(10):1335 (DOI 10.3390/biology12101335))
- Plant foods do not naturally contain vitamin B12. (NIH Office of Dietary Supplements. Vitamin B12 Fact Sheet for Health Professionals (updated 2025-07-02))
- ICMR-NIN: vitamin B12 can be obtained from yoghurt or curd. (ICMR-NIN. Dietary Guidelines for Indians 2024)
- Some plant foods are fortified with vitamin B12, including many breakfast cereals and nutritional yeasts. (NIH Office of Dietary Supplements. Vitamin B12 Fact Sheet for Health Professionals (updated 2025-07-02))