Vitamin B12 (cobalamin) is essential for nerve function, red blood cell formation, and DNA synthesis. Deficiency is common in vegans, vegetarians, older adults, and those with absorption issues — affecting up to 20% of Australians over 60. B12 supports energy production, cognitive function, and mood regulation. Methylcobalamin is the bioactive form preferred by many practitioners, while cyanocobalamin is the most affordable and stable form.
How it works
B12 serves as a cofactor for methionine synthase (converting homocysteine to methionine) and methylmalonyl-CoA mutase. It is essential for myelin synthesis (nerve sheath maintenance), red blood cell maturation, and one-carbon metabolism pathways that regulate DNA synthesis and methylation.
Evidence-based uses
Methylcobalamin form is preferred. Especially important for vegetarians/vegans.
Clinical Evidence
Systematic review found B12 supplementation significantly reduced fatigue in deficient individuals, with improvements in energy and cognitive function within 2-4 weeks of treatment.
B12 is essential for myelin synthesis and neurotransmitter production. Deficiency causes cognitive impairment, brain fog, and memory issues. Supplementation most effective in those with low or deficient levels. Methylcobalamin preferred for neurological benefits.
B12 deficiency is a recognised cause of hair loss. Red blood cells require B12 to carry oxygen to hair follicles. When levels are low, follicles cannot grow new hair efficiently. Most beneficial for those with confirmed deficiency — routine supplementation in B12-replete individuals is unlikely to improve hair growth.
Safety
Metformin reduces vitamin B12 absorption over time. If you take metformin, regular B12 monitoring is recommended — supplementation may be necessary.
Long-term PPI use (omeprazole, pantoprazole) reduces stomach acid needed for B12 absorption. Consider sublingual or injection forms.
Compare prices
3 products compared across Australian retailers. Sorted by price per serve.
Scroll for more
| Product | Price | /serve | |
|---|---|---|---|
Best NOW Foods Methyl B-12 1000 mcg, 100 Lozenges iHerb | $14.20 | $0.14 | |
Thorne Thorne Methylcobalamin Thorne | $28.00 | $0.47 | |
Thorne Methylcobalamin 60 Capsules Thorne | $29.99 | $0.50 |
Prices in AUD. Some links are affiliate links — we may earn a commission at no extra cost to you.
Get a personalised supplement stack based on your health goals, age, medications, and preferences.
Also consider
Vitamin
Vitamin B7 that supports keratin production for hair, skin, and nails.
Mineral
Essential mineral involved in immune function, wound healing, and cell division.
Mineral
Essential mineral for oxygen transport and energy production.
Protein
Structural protein that supports skin elasticity, hair strength, and joint health.
Get a personalised dosage recommendation based on your age, weight, and health goals
Vitamin B12 has 2 known interactions. Check if it's safe with your medications.
Price drops, new products, and research updates for vitamin b12 supplements. One email per week, unsubscribe anytime.
This information is for educational purposes only and is not intended as medical advice. Always consult a healthcare professional before starting any supplement. Evidence ratings are based on peer-reviewed clinical research. Individual results may vary.