B-Complex
Essential when skipping animal products — energy and nerve function.
- Typical dose
- 1 capsule
- When to take
- Morning
- Onset
- Days to weeks for energy, mood, and cognitive effects in deficient individuals
What it does
Benefits
- Supports energy metabolism — every B vitamin is a cofactor in ATP production
- Important for nerve function and neurotransmitter synthesis
- Folate (B9) essential for DNA synthesis and methylation
- Methylated forms benefit people with MTHFR variants
The science
How it works
B vitamins are water-soluble cofactors in dozens of metabolic enzymes. They're not stored (except B12), so steady intake matters. Deficiencies in B1, B6, B9, B12 are the most common clinically.
Getting it right
Dose & timing
Dose guidance
One capsule of a balanced B-complex daily. Avoid mega-B products (500+ mg of each) — no added benefit and some cause side effects.
Best time to take
Morning with food. Some people find it energizing — avoid late-day dosing.
Is it for you?
Who should (and shouldn't) take it
Good for
- Vegans (B12 gap)
- High-stress periods (Bs deplete faster)
- Alcohol use (impairs B1/thiamine)
- MTHFR variants (methylated forms)
Skip or ask a doctor if
- You already take high-dose individual B vitamins
- You have a rare Leber's hereditary optic neuropathy (avoid cyanocobalamin)
Know before you start
Side effects & safety
- Bright yellow urine (harmless — B2)
- Flushing from high-dose niacin (B3)
- Neuropathy from chronic high-dose B6 (>200 mg/day long-term)
Shopping guide
Forms & what to look for
- Standard B-complex
Balanced, affordable
- Methylated B-complex
Methylfolate + methylcobalamin — preferred for MTHFR
- Activated B-complex
All Bs in coenzyme forms; pricier
Combining
Stacks well with / avoid pairing
Stacks well with
Common questions
FAQ
Do I need a B-complex if I take a multi?
Usually not — most multis cover Bs adequately. B-complex is for targeted support or deficiency.
Methylated — do I really need it?
Beneficial for ~40% of people with MTHFR variants. For everyone else, standard forms work fine and cost less.
Will it boost my energy immediately?
Only if you were deficient. For well-fed people, effects are subtle.
References
Sources & further reading
Educational only, not medical advice. Check with a clinician before starting anything new, especially if you're on medication or pregnant.
Other supplements
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