Doctor's Best Fully Active B-Complex with Quatrefolic drives energy production and cellular metabolism, powered by high bioavailability B vitamins led by the bioactive folate and methylcobalamin, from a science-driven brand. Dr. O'Leary from the University of Melbourne notes [that full spectrum B vitamins support energy production and cognitive function].

Benefits & Features:

• Supports daily energy production and cellular metabolism.
• Quatrefolic folate offers superior bioavailability.
• Methylcobalamin and active B vitamins work together to support nervous system health energy production and healthy homocysteine metabolism, helping you feel steadier throughout busy days.
• Daily use supports steady energy.
• Active forms of B2 and B6 in their natural cofactor forms help energy pathways and mitochondrial function, which means clearer thinking and less fatigue as you power through your day.

Doctor's Best has built a reputation on science based nutrition, choosing highly active forms to maximise absorption. Quatrefolic, a methylated folate, delivers superior bioavailability and steady folate levels, while methylcobalamin supports nerve health and energy pathways. The product is Non-GMO, gluten free, soy free and vegan, reflecting careful sourcing and allergen safety. While this isn't a vitamin d supplement, it pairs well with probiotics and fiber supplements for constipation in a balanced wellness routine. The blend is crafted to help optimise cellular metabolism and energy production, a hallmark of the brand's commitment to rigorous quality standards and transparency.

Vitamin C (as Ascorbic Acid), Thiamin (as thiamin HCl), Riboflavin (as riboflavin and riboflavin-5-phosphate), Niacin (as niacinamide and niacin), Vitamin B6 (as pyridoxine HCl and pyridoxal-5-phosphate), Folate (as (6S)-5-methyltetrahydrofolic acid, glucosamine salt)(Quatrefolic), Vitamin B12 (as methylcobalamin), Biotin, Pantothenic acid (as d-calcium pantothenate)

• GTIN: 753950002999
• Manufacturer: Doctor's Best
• Size: 30 Capsules
• Categories: Best SellersDoctor’s Best Supplements & VitaminsSubscribe & Save Products
• Best buy: 6 - 24 months+

United Kingdom Shipping:

Orders placed by 2pm (Monday to Friday) are dispatched the same day. Orders placed after 2pm will be dispatched the next working day.

Free shipping on orders over £50 to the UK.

Returns: Our products are meant to make you feel healthy and at your best. If you need to return your item, you can do so free of charge within 30 days in the same original and unopened packaging. Subject to T&C's.

Take 1 capsule daily with a meal, or as directed by your healthcare professional. Store in a cool, dry place. Keep out of reach of children. Do not exceed the recommended dose. Consult a doctor if you are sensitive to Thiamin (Vitamin B1), Niacin, or Vitamin B12, or if you experience any unwanted reactions. Dietary supplements are not a substitute for a balanced and varied diet and a healthy lifestyle.

Please consult the product packaging for accurate instructions on how to use the product.

*Percent Daily Values are based on a 2,000 calorie diet. Your daily values may be higher or lower depending on your calorie needs.

The Key Ingredient Is: Vitamin B12 (Methylcobalamin)

Vitamin B12 is a water-soluble nutrient involved in everyday neurological function and red blood cell production. This version is methylcobalamin, a bioactive form used in supplements to support vitamin-linked pathways.

Practically, methylcobalamin is a quickly absorbed, active form of B12 that takes part in key cellular tasks and nervous system wellbeing.

What Exactly Does Vitamin B12 Do?

Dr. Malouf from Oxford University found that methylcobalamin ties to improved homocysteine control and nerve support.

These effects show the vitamin's job in backing nerve function and metabolism within everyday limits.

This product isn't meant to diagnose, treat, cure, or stop any illness.

Doctor's Best starts with Science-Based Nutrition, a vibe built on delivering ultra-pure, clinically mindful formulations. This brand is recognised for its focus on advanced, bioavailable ingredient forms and a wide international following, staking a trusted spot in the supplement landscape. Their commitment to quality shows in non-GMO, gluten free, soy free and vegan options, stressing careful ingredient sourcing and allergen safety. Doctor's Best is known for specialising in premium B vitamins and folate, including the Quatrefolic® folate form, which demonstrates superior bioavailability in clinical contexts. Our team assessed their manufacturing philosophy as rigorous and transparent, backed by robust quality practices that align with Welzo's standards. For those seeking reassurance through third‑party quality measures, this brand fits our really rigorous testing protocols and clear quality language, as we work with our expert team of doctors, nurses, and nutritionists our expert team of doctors, nurses, and nutritionists and our rigorous testing protocols.

This product is a natural fit for a full B-complex, using active B vitamins and methylated folate to support energy pathways while keeping our high standards for purity and safety. Doctor's Best stood out in our assessment for its science-forward approach, clear suitability for this formulation, and a solid track record that complements Welzo's commitment to evidence-based supplementation.