Vitamin B12: energy, nervous system and duo with B9

A cofactor for several key enzymes, it plays a central role in energy metabolism, red blood cell formation, normal functioning of the nervous system, and homocysteine metabolism, working in tandem with vitamin B9. This versatility makes it a discreet ally at every stage of motherhood, from preconception and pregnancy through to the postpartum period and perimenopause. Cobalamin exists in several forms (methylcobalamin, adenosylcobalamin, hydroxocobalamin, cyanocobalamin), only some of which are directly active in your cells. Its form and quality determine how well it is absorbed: a clean matrix, a well-absorbed form and traceable manufacturing are what we look for. A regular intake of this vitamin helps to meet your body's needs and support the normal functioning of several systems.

In its natural form, Vitamin B12 is found almost exclusively in foods of animal origin: calf's liver (around 60 µg per 100 g), mackerel (approximately 19 µg per 100 g), salmon (approximately 3 µg per 100 g), egg (1.9 µg), aged cheeses such as Emmental (3.1 µg) and dairy products, according to data from the ANSES Ciqual nutritional composition table. Its absorption depends on several factors: the food matrix, your digestive status, the production of intrinsic factor by the stomach, and your overall nutritional state — all of which can affect the amount actually used by the body. Prolonged cooking at high heat, certain storage methods or diets that exclude animal products can make this intake more variable from one day to the next. A vitamin B12 deficiency can then develop gradually, with symptoms that remain subtle for a long time, affecting energy levels, the nervous system or red blood cell formation. For strictly vegetarian or vegan women, diet alone is not sufficient to meet requirements for this vitamin: a regular supplement becomes a useful reference point — without any guilt — to help maintain stable B12 levels.

As a food supplement, Vitamin B12 comes in two main forms: cyanocobalamin, a widely used synthetic form that must first be converted by the liver, and methylcobalamin, a naturally active form directly usable by your body's enzymes. Methylcobalamin offers good cellular retention and participates directly in the methylation cycle, working in tandem with vitamin B9 in its active form. At Jolly Mama, vitamin B12 is provided as methylcobalamin in our multivitamins, which contributes to good bioavailability. This form can be found, for example, in our complete pregnancy supplements and our vitamin B9 supplements (the methylation duo). In terms of quality, we look at the exact form of cobalamin, the purity of raw materials, traceability and the absence of unnecessary additives.

Adequate vitamin B12 intakes by life stage

• Adult woman (18+): 4 µg/day (source: EFSA 2015)
• Pregnancy: 4.5 µg/day (source: EFSA 2015)
• Breastfeeding: 5 µg/day (source: EFSA 2015)
• UL (upper safety limit): Not established (source: EFSA)

Methylcobalamin vs cyanocobalamin: what sets them apart

• Directly active form: Methylcobalamin = yes, direct coenzyme / Cyanocobalamin = no, hepatic conversion required
• Origin: Methylcobalamin = natural form / Cyanocobalamin = synthetic form
• Cellular retention: Methylcobalamin = good retention / Cyanocobalamin = lower
• Presence of a residual cyanide group: Methylcobalamin = no / Cyanocobalamin = yes, in very small amounts

Mama tip: Vitamin B12 never works alone — it functions in tandem with vitamin B9 in the methylation cycle, which is central to preconception and pregnancy. The idea is not to supply one without the other, but to combine B9 and B12 in their active forms (methylcobalamin and active folates such as Quatrefolic®). This is the thinking behind our women's multivitamins, designed so that these two vitamins work together, at your pace and according to the stage you are going through.

Key takeaway: Vitamin B12, or cobalamin, is a water-soluble vitamin that plays a key role in energy metabolism, red blood cell formation and normal nervous system function. According to EFSA, adequate intakes are 4 µg/day for adult women, 4.5 µg/day during pregnancy and 5 µg/day during breastfeeding. As this vitamin is found almost exclusively in foods of animal origin, maintaining a regular intake is an important consideration for vegetarian or vegan women, to avoid a silent deficiency. At Jolly Mama, vitamin B12 is provided in its active form, methylcobalamin.