Our B Complex is a high-strength formula with active forms of vitamin B6, folate and vitamin B12.
Key Benefits
- All eight B-vitamins — contribute to normal energy-yielding metabolism, normal functioning of the nervous system, normal psychological function, and reduction of tiredness and fatigue.
- Vitamin B12 as methylcobalamin. Vitamin B12 comes in several forms, including methylcobalamin, adenosylcobalamin and cyanocobalamin, all of which the body can use.
- Vitamin B6 as P5P (Pyridoxal-5-Phosphate) — the metabolically active form, at 8mg (571% NRV).
- Folate as 5-MTHF (methyltetrahydrofolate) — folate contributes to normal psychological function and the reduction of tiredness and fatigue.
- Choline (82.2mg) and inositol (100mg) added alongside.
Why Dr Marks?
We use the active forms of B6, folate and B12, at high-strength doses.
Take one capsule daily, ideally with food and a glass of water. B-vitamins are water-soluble with no established Tolerable Upper Intake Level for most forms used here; however, please check with your GP first if you take regular prescribed medication that can affect B-vitamin levels, or are on dialysis. Contains biotin (200µg), which can interfere with some laboratory blood tests (such as thyroid hormone tests) — tell your doctor or clinic you take this supplement before having a blood test. If you take anticonvulsant medication (such as phenytoin) or levodopa, check with your GP or pharmacist first. Suitable for vegans and vegetarians. Made in a factory that also handles milk, egg, fish and crustaceans. 60 capsules per pouch. Food supplements should not be used as a substitute for a varied and balanced diet and a healthy lifestyle.
Formulation Comparison
Dr Marks Vitamin B Complex vs Typical High-Street Supplement
60 vegan capsules · 1 a day · 30p/daySuitable for vegans & vegetarians
| What to look for | Dr Marks Vitamin B Complex | Typical High-Street Supplement |
|---|---|---|
| Active forms | Dr MarksMetabolically active B6 as P5P (8mg, 571% NRV), methylfolate (400µg 5-MTHF) & methylcobalamin (1,000µg) |
Typical High-StreetPyridoxine HCl & synthetic folic acid |
| Complete spectrum + co-factors | Dr MarksAll 8 B-vitamins plus 82.2mg Choline, 100mg Inositol & 20mg PABA |
Typical High-StreetBasic B-vitamins with no choline or inositol |
| Daily dose | Dr Marks1 vegan & vegetarian capsule a day |
Typical High-StreetTablets with artificial coatings |
| Excipients & coatings | Dr MarksNo titanium dioxide, talc, tablet glazes or artificial colours |
Typical High-StreetBulking agents, tablet glazes and artificial colours |
| Format & packaging | Dr MarksFlat, letterbox-friendly resealable pouch |
Typical High-StreetBulky plastic tubs or blister packs |
| Formulated by | Dr MarksPractising UK GPs |
Typical High-StreetGeneric mass-market contract formulas |
Compared against common single-form or standard A–Z high-street tablet formulations.Made in a UK factory that also handles milk, egg, fish and crustaceans.
A GP’s View on Supplement Timelines
Consistent Daily Use: What Happens in the Body
Many supplement brands print fixed charts promising you will “feel more energy in Week 2” or “see thicker hair in Month 2”. As practising UK GPs, we won’t do that. What happens when you take a supplement depends on whether you are topping up an everyday diet (where nutrients work quietly in the background and you may not “feel” a sudden change) or correcting a low level found on a GP blood test.
Days 1–7
Daily routine & digestive comfort
Take 1 capsule a day with a main meal and water. Taking your capsule with food is gentler on the stomach and helps fat-soluble vitamins absorb normally.
Note: Vitamin B2 (riboflavin) naturally turns urine bright yellow — this is harmless and simply shows water-soluble B vitamins passing through.
Weeks 2–6
Steady daily nutritional intake
Consistent daily intake helps top up your diet every day rather than in sporadic bursts. Water-soluble nutrients (such as B vitamins and vitamin C) are used daily and aren’t stored in large amounts, while fat-soluble nutrients (such as vitamin D) build up gradually with steady daily intake.
Weeks 8–12 (1–2 pouches)
Long-term maintenance & GP blood re-checks
Red blood cells turn over roughly every 90 to 120 days. When a GP treats a confirmed low level (such as vitamin B12 or vitamin D), NICE and NHS guidance typically schedules a clinical review or follow-up check around 3 months. For everyday dietary top-ups, steady ongoing habits matter most.
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Dr Marc CrutchleyMBChB MRCGP MSc BSc (Hons), Co-founder
Dr Mark WilshereMBChB MRCGP DCH BSc (Hons), Co-founder
GP-Formulated in the UK✓ GMC-Registered Practising UK GPs · 40+ Years Combined Experience
Meet the GPs behind Dr Marks
Formulated by Dr Marc Crutchley and Dr Mark Wilshere, practising UK GPs.
With over 40 years of combined clinical experience as GMC-registered UK GPs, we formulate every Dr Marks supplement using bioavailable nutrient forms at meaningful daily doses — in clean plant-based capsules with zero synthetic fillers or binders.
