Core Nutritional

B-Complex (Complete)

💊 What it does

A B-complex supplement provides all eight B vitamins in a single formulation: B1 (thiamine), B2 (riboflavin), B3 (niacin), B5 (pantothenic acid), B6 (pyridoxine), B7 (biotin), B9 (folate), and B12 (cobalamin). B vitamins work as a team — many are cofactors for the same biochemical pathways, particularly energy metabolism and one-carbon metabolism. Taking them together in balanced amounts avoids the imbalances that can arise from high-dose individual B vitamin supplementation. A B-complex is particularly useful as an insurance policy for plant-based eaters who may be low in B12, riboflavin, and potentially B6.

👤 Who needs it

Vegans and plant-based eaters wanting broad B-vitamin coverage. People under high stress (B vitamins are depleted by cortisol). Heavy alcohol drinkers (alcohol depletes multiple B vitamins). Older adults with declining absorption. People taking metformin (depletes B12 and folate). Those with MTHFR variants (look for methylated B-complex with methylcobalamin + methylfolate).

🥦 Food sources first

B vitamins are found throughout plant foods but in varying amounts. Best sources: nutritional yeast (comprehensive B-vitamin profile including B12 when fortified), wholegrains, legumes, leafy greens, nuts, seeds, and fortified foods. However, B12 from food is unreliable for strict vegans.

🗓 When to supplement

As a convenient all-in-one B-vitamin supplement. For vegans wanting broader B-vitamin coverage beyond standalone B12. During periods of high stress or illness.

🏷 Best form to look for

Look for methylated B-complex containing methylcobalamin (B12) and methylfolate (5-MTHF) rather than cyanocobalamin and folic acid — superior for people with MTHFR variants and generally better retained. Avoid mega-dose B6 formulations (above 10 mg B6/day long-term).

⏰ When to take it

Morning with food. B vitamins are water-soluble — taking with breakfast is conventional. Note: riboflavin (B2) will turn urine bright yellow — harmless and expected.

⚡ Interactions & combinations
High B6 above 10 mg/day long-term causes peripheral neuropathy — check B6 content of your B-complex. Biotin in B-complex interferes with many blood tests (thyroid, troponin) — inform GP and stop 48 hours before blood tests. Folate can mask B12 deficiency in blood tests.
🛡 Safety notes
Generally very well tolerated. The B6 neuropathy risk at high long-term doses is the primary safety concern. The biotin blood test interference is practically important.
🌿 Vegan note
B-complex supplements are synthesised by fermentation — plant-based. Check for animal-derived excipients in capsule shells.
Strong evidence
Well-established by multiple high-quality clinical studies.
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Disclaimer: As with any supplement, it is best to consult with a healthcare professional before starting, particularly if you are pregnant, nursing, or taking prescription medications.