Vitamin B12 deficiency is one of the most underdiagnosed nutritional deficiencies in the UK. It develops slowly, its symptoms are often attributed to stress or ageing, and by the time it is detected, neurological effects may already be present.
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Who is at risk of B12 deficiency in the UK?
B12 is found almost exclusively in animal products, making deficiency particularly common among:
- Vegans and vegetarians — the highest risk group; plant foods contain virtually no B12
- Adults over 50 — stomach acid production decreases with age, impairing B12 absorption from food
- People taking metformin (for type 2 diabetes) — metformin significantly reduces B12 absorption
- People on proton pump inhibitors (PPIs) — acid-suppressing drugs reduce B12 release from food
- People with pernicious anaemia or Crohn’s disease — absorption from the gut is impaired
Symptoms of B12 deficiency
- Extreme tiredness and fatigue
- Pins and needles in hands and feet
- Sore, red tongue (glossitis)
- Mouth ulcers
- Disturbed vision
- Irritability and depression
- Problems with memory, understanding and judgement
If you experience neurological symptoms, see your GP for a blood test before supplementing.
Which form of B12 is best absorbed?
B12 supplements come in three main forms:
Cyanocobalamin — the cheapest and most common form. Synthetic, requires conversion by the body. Adequate for most healthy people.
Methylcobalamin — active form, used directly without conversion. Preferred for neurological support and people with MTHFR gene variants.
Hydroxocobalamin — the form used in NHS B12 injections. Stays in the body longer than other forms, releasing B12 gradually. Excellent for people with absorption issues.
Tablets vs. liquid drops: which absorbs better?
Standard tablets rely on normal stomach absorption, which is exactly what fails in many B12-deficient people. Liquid drops taken sublingually (under the tongue) bypass the stomach entirely, absorbing directly through the mucous membranes. This makes liquid B12 significantly more effective for people with digestive absorption issues or those over 50.
How much B12 do you actually need?
The UK NRV for B12 is 2.5 mcg per day. However, because B12 absorption is inefficient (only 1-2% of large doses is absorbed passively), supplements typically provide 100-1000 mcg to ensure adequate uptake. Higher doses are not harmful — B12 is water-soluble and excess is excreted.
BestB12 — liquid hydroxocobalamin drops
BestB12 provides vitamin B12 as hydroxocobalamin in a convenient liquid drop format, for sublingual administration. Each serving delivers a meaningful dose of B12 in a form the NHS uses for injection-grade treatment, in a format accessible without prescription.
Suitable for vegans, people over 50, and anyone with digestive absorption concerns.
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