B1 (thiamine) is essential for carbohydrate metabolism and nervous system function; B2 (riboflavin) supports energy metabolism and antioxidant cell protection; B3 (niacin) contributes to normal nervous system function and reduced fatigue; B5 (pantothenic acid) is involved in steroid hormone and vitamin D synthesis; B6 (pyridoxine) supports protein and amino acid metabolism and neurotransmitter synthesis; folate (B9) is essential for cell division and DNA synthesis; B8 (biotin) supports macronutrient metabolism and normal hair and skin; and B12 (cobalamin) is needed for red blood cell formation and nervous system function.

Quatrefolic is L-methylfolate, the biologically active form of folate the body uses directly with no conversion needed — crucial because a significant share of the population carries an MTHFR gene variant that reduces their ability to convert synthetic folic acid into active methylfolate. Around 40% of the world’s population has at least one MTHFR mutation, and about 10% carries two copies, reducing enzyme activity by 30–70%. Each capsule delivers 400µg of folate equivalents as Quatrefolic (200% NRV), bypassing this enzymatic step entirely.

B12 is provided as methylcobalamin (1,000µg), the active form directly usable by the body, unlike cyanocobalamin which requires metabolic conversion. B6 combines pyridoxine HCl with pyridoxal-5-phosphate (P5P), the active coenzymatic form. B2 pairs riboflavin with riboflavin-5-phosphate, also active. This systematic use of active forms is what distinguishes Fully Active B Complex from standard B complexes using only basic synthetic forms.

Take 1 capsule a day with a meal, ideally morning or midday, since B vitamins support energy metabolism. Particularly relevant for people with persistent fatigue, high stress, vegetarians and vegans (B12 needs), people with the MTHFR variant, and older adults with naturally reduced B vitamin absorption. This 30-capsule size covers one month — a good way to check tolerance before moving to the larger 60-capsule size, also available at Herba Barona.

Do not exceed the recommended daily dose. If pregnant, breastfeeding, or on medical treatment, consult a healthcare professional before use. This food supplement is not a substitute for a varied and balanced diet and a healthy lifestyle.

Folic acid vs. Quatrefolic — what’s the difference?

Folic acid is the synthetic form requiring several enzymatic conversion steps, including the MTHFR-dependent one, to become usable. Quatrefolic is already L-methylfolate, the final active form, usable immediately — particularly valuable for people with the MTHFR variant.

Is yellow-coloured urine normal with a B complex?

Yes, completely normal and harmless — riboflavin (B2) is a fluorescent yellow pigment; any excess is cleared by the kidneys, turning urine bright yellow. It’s simply a sign your body is excreting surplus riboflavin.

Can it be combined with other supplements?

Yes — it pairs well with magnesium, vitamin D, omega-3 or vitamin C. Avoid taking it alongside another multivitamin to prevent dosage overlap on certain vitamins.

Herba Barona is an independent specialist supplement shop in the heart of Paris — established in 2006. What you order is genuinely on our shelves: we ship from our own stock, with no dropshipping and no long waits.

Visit us at 10 rue Théophile Roussel, Paris 12 — or use Click & Collect and pick up your order in-store. We also deliver across France and Europe. Friendly, expert advice in English from our team.

Where is the shop?

Herba Barona is at 10 rue Théophile Roussel, 75012 Paris — a two-minute walk from Ledru-Rollin (line 8), close to Bastille. Open Tuesday to Saturday, 9:30 am–6:30 pm.

Can I order online or collect in store?

Yes. We ship across France and Europe under the same conditions as our French store, or choose Click & Collect to pick up your order for free at our Paris shop.