Vitamin B Complex

The 8 B vitamins (B1, B2, B3, B5, B6, B7, B9, B12) function interdependently in metabolic pathways. They collaborate in energy production (Krebs cycle), neurotransmitter synthesis, and amino acid metabolism. Taking a B complex ensures optimal synergy — some B vitamins improve the absorption or activation of others (B2 activates B6, B12 works with B9 on homocysteine). Excessive individualised dosing of certain B vitamins without the others can create imbalances.

This is THE crucial question on any B complex. Cyanocobalamin is the least expensive synthetic form, whose conversion into active methylcobalamin requires several enzymatic steps. Methylcobalamin and adenosylcobalamin are the directly usable bioactive forms, particularly important for people with an MTHFR mutation (very common: 40–60% of the population). Check the form of B12 on the Kiki Health label — it is a strong indicator of the overall product quality.

B vitamins are essential for everyone, but certain groups have particularly high needs: vegans and vegetarians (near-absence of B12 in plant foods), elderly people (reduced B12 absorption), pregnant women or those trying to conceive (B9 folate essential for neural development), chronically stressed people (B vitamins are rapidly depleted by chronic stress), and people who consume alcohol regularly (depletion of B1 and B12).

Yes, this is its most documented and EFSA-recognised action. Vitamin B1 (thiamine) and B2 (riboflavin) contribute to normal energy metabolism, B3 (niacin) and B5 (pantothenic acid) reduce fatigue, and B12 supports normal functioning of the nervous system. These health claims are officially authorised in the EU. For intense chronic fatigue, combine the B Complex with NMN and Ionic Iron (if iron deficiency confirmed by blood test).

Yes, all B vitamins are water-soluble, meaning excess is eliminated in the urine (hence the bright yellow colour of urine after taking B vitamins — this is riboflavin B2, harmless). The risk of overdose is low at recommended doses, but vitamin B6 at very high chronic doses (>200 mg/day for months) can cause reversible sensory neuropathy. Stay within recommended doses.

In the morning with breakfast, to benefit from an energising effect throughout the day and facilitate absorption with food. Taking on an empty stomach may cause mild nausea in some people. Avoid evening intake (possible stimulating effect on sleep). If you split the dose into two doses, the second can be taken at midday.

Metformin (type 2 diabetes) reduces vitamin B12 absorption — supplementation is often recommended for patients on metformin. Proton pump inhibitors (omeprazole) also reduce B12 absorption. Alcohol depletes thiamine (B1). B6 can reduce the efficacy of certain antiepileptic medications. Inform your doctor of your B vitamin supplementation.

SuperKure is the official distributor of Kiki Health in France. Order at superkure.fr with 24–48h delivery from our French warehouse. No customs fees, free delivery from €60. Also find the Organic Vitamin C and ionic mineral concentrates from Kiki Health to build your complete basic micronutrition stack.