The B12 guide

Why this is the one supplement every vegan should know about

B12 is produced by bacteria, not by plants or animals. Animals obtain vitamin B12 from bacteria in their environment, through their feed or via supplementation. In modern farming systems, many livestock are supplemented because they no longer obtain enough B12 naturally.

B12 cannot be obtained reliably from plant foods. Spirulina and fermented foods are sometimes cited as sources, but the compounds they contain are not bioavailable in humans. Direct supplementation is the correct approach.

How much, what form, how often

• Form: Methylcobalamin and cyanocobalamin are both effective. Cyanocobalamin has the strongest evidence for stability and supplementation, while methylcobalamin is also widely used and readily available.
• Dose: 50-100 mcg daily. Or 1,000 mcg, 2-3 times a week. Or 2,000 mcg once a week.
• How to take: Chewable, sublingual or swallowed tablets are all effective. Consistency matters far more than the form you choose.

Only a small proportion of each dose is absorbed, which is why larger intermittent doses work well. Excess vitamin B12 is generally excreted in the urine.

Brands in India

• HealthKart B12
• Carbamide Forte B12
• Wellbeing Nutrition Methylcobalamin
• Inlife Methylcobalamin
• Himalayan Organics B12
• Nature Made (imported, on Amazon)

₹300-₹600 for several months.

How to test

Ask your doctor for:

• Serum vitamin B12 is the most common screening test. If results are borderline or symptoms are present, your doctor may also recommend methylmalonic acid (MMA) and/or homocysteine for a more complete assessment.
• Homocysteine (more accurate marker of functional B12 status)
• MMA (methylmalonic acid) if you want to be thorough - most accurate but expensive

Testing frequency depends on your medical history, symptoms and your healthcare provider's advice, but many people who supplement consistently have their levels checked periodically as part of routine bloodwork.

Symptoms of deficiency

You don't want to wait for symptoms - by the time they show, deficiency is advanced. But for reference: fatigue, tingling in hands/feet, balance problems, brain fog, low mood, pale skin, glossitis (smooth, sore tongue).

Common myths

Can you get enough B12 from food?

For vegans, not reliably.

While some plant milks, breakfast cereals and nutritional yeast are fortified with vitamin B12, the amounts vary widely between products. Fortified foods can contribute to your intake, but a dedicated supplement remains the simplest and most reliable way to meet your needs.

What if I forget a dose?

Don't panic.

Vitamin B12 is stored in the liver, so missing an occasional dose isn't usually a problem. Simply resume your normal supplementation schedule rather than doubling up unnecessarily.

Disclaimer

This chapter is intended for educational purposes only and should not replace personalised medical advice. Supplement needs can vary depending on your age, medical history, medications, digestive health and existing vitamin B12 status.

Before starting or changing any supplement regimen, speak with your doctor or a registered dietitian, especially if you're pregnant, breastfeeding, have a medical condition or have previously been diagnosed with a vitamin B12 deficiency. Blood tests and personalised advice are the best way to determine the right dose for you.