vitamin B₁₂

noun

-ˈbē-ˈtwelv 

1

: a complex cobalt-containing compound C₆₃H₈₈CoN₁₄O₁₄P that occurs especially in liver, is essential to normal blood formation, neural function, and growth, and is used especially in treating pernicious and related anemias and in animal feed as a growth factor

called also cyanocobalamin

2

: any of several compounds similar to vitamin B₁₂ in action but having different chemistry

Examples of vitamin B₁₂ in a Sentence

Recent Examples on the Web

Less frequent side effects can include chest discomfort, weakness, headache, rhinitis, hypoglycemia and vitamin B12 deficiency (with long-term metformin use). —Leslie Baumann, Miami Herald, 27 Feb. 2025

The secret behind the extra dose of hydration is a blend of ingredients like magnesium, vitamin B12, and coconut water, all rich in vitamins that act as humectants to prevent dryness. —Conçetta Ciarlo, Vogue, 24 Feb. 2025

One study found adding a salmon protein supplement to a person’s diet for eight weeks increased their serum vitamin B12 concentrations.6 2. —Julie Marks, Verywell Health, 21 Feb. 2025

Key ingredients: Bisabolol, vitamin B12, gallic acid derivatives. —Denise Primbet, Glamour, 21 Feb. 2025

For instance, vegan diets can be low on levels of protein, vitamin B12, iron, calcium, omega-3 fatty acids, vitamin D and zinc, says Young. —Daryl Austin, USA TODAY, 11 Feb. 2025

In a healthy population, only about 3 to 4 percent of people are vitamin B12 deficient, compared with the 29 percent of people with type 2 diabetes taking metformin, says Bridges. —Tom Gavin, EverydayHealth.com, 29 Jan. 2025

This usually requires vegans to eat fortified foods or take a variety of supplements, especially for nutrients like vitamin B12, which is only found in animal products. —Daryl Austin, USA TODAY, 11 Feb. 2025

The new study found a higher prevalence of micronutrient deficiencies, especially vitamin B12, in people who took metformin. —Kaitlin Sullivan, Health, 6 Feb. 2025

Word History

First Known Use

1948, in the meaning defined at sense 1

Kids Definition

vitamin B₁₂

noun

-ˈbē-ˈtwelv

: a member of the vitamin B complex that contains cobalt, occurs especially in liver, and is needed for normal blood formation, nerve function, and growth

also : any of several other compounds with similar activity

Medical Definition

vitamin B₁₂

noun

-ˈbē-ˈtwelv 

1

: a complex cobalt-containing compound C₆₃H₈₈CoN₁₄O₁₄P found in animal products (as meat and eggs) that is essential to normal blood formation, neural function, and growth and is used especially in treating pernicious and related anemias and in animal feed as a growth factor

called also cyanocobalamin

2

: any of several compounds similar to vitamin B₁₂ in action but having different chemistry