Vitamin B12
Vitamin B12 is a water-soluble vitamin needed for energy, red blood cell formation, nerve health and overall wellbeing. It is naturally found in animal-based foods, which means that people following vegetarian or vegan diets — or those with reduced absorption — may have lower levels.
B12 supplements can be a helpful way to support energy and general health when dietary intake is limited. They work best as part of a wider nutrition and lifestyle approach, and do not replace medical assessment when deficiency is suspected.
What It Is
Vitamin B12 (cobalamin) is an essential vitamin involved in:
energy production
red blood cell formation
nerve function
DNA synthesis
mood and cognitive processes
It is absorbed in the small intestine with the help of intrinsic factor, a protein made in the stomach. Because it relies on several steps for absorption, some people may find it harder to maintain optimal levels.
What It’s Used For
B12 supplements are commonly used to support:
energy and fatigue
concentration and cognitive function
healthy red blood cell formation
mood and psychological wellbeing
nerve health
diets low in animal products
periods of higher nutritional demand
Plant-based eaters and older adults often benefit from reviewing B12 intake.
What the Evidence Says
Research consistently shows that B12:
is essential for normal energy metabolism
supports nervous system function
contributes to red blood cell formation
plays a role in mood and cognitive health
Studies also show that:
deficiency is more common in vegans, vegetarians and older adults
certain medications may reduce absorption
low stomach acid (common with age or stress) can impact B12 uptake
fortified foods can contribute meaningfully to intake
Testing B12 levels through a GP or private lab can provide useful context when symptoms or dietary patterns suggest reduced intake.
When It Can Be Helpful
B12 may be helpful to consider if you:
follow a vegan or vegetarian diet
consume very little animal protein
feel low in energy or fatigued
have reduced appetite or restricted dietary intake
are pregnant or breastfeeding (with guidance)
are an older adult with reduced stomach acid
have low B12 on a blood test
have increased cognitive or neurological demands (e.g. stress, busy schedules)
It may also be supportive when exploring low energy, mood changes or concentration difficulties alongside dietary review.
When Caution Is Needed
B12 supplements are generally safe, but caution is needed if:
you are using high-dose B12 sprays or injections
you have known B12 deficiency — this requires medical guidance
you have very high B12 levels on blood tests
you take multiple fortified products plus supplements
you react to certain forms (cyanocobalamin vs methylcobalamin)
If symptoms are severe or persist despite good intake, it’s important to discuss this with your GP.
Why It’s Not Always the First Step
While B12 plays a central role in energy and mood, supplements aren’t always the first thing to focus on.
Before considering B12 supplementation, it’s helpful to explore:
regular, balanced meals
adequate protein intake
managing stress and supporting digestion
iron status (energy relies on both iron and B12)
sleep quality
intake of B12-rich foods or fortified alternatives
Supplements can be helpful, but foundation habits often make the biggest difference.
Nutrition Support
You can support B12 naturally through foods such as:
fish (salmon, trout, tuna)
eggs
dairy products
meat and poultry
fortified plant milks
fortified cereals
nutritional yeast
B12 absorption is supported by:
good stomach acid levels
balanced meals
reducing stress around eating
including protein and healthy fats
Plant-based eaters often rely on fortified foods and supplements to meet needs.
If You’re Unsure Whether B12 Is Right for You
If you’re unsure whether your symptoms relate to B12 intake or absorption — or you want help interpreting a blood test — we can explore this together. Sometimes dietary adjustments are enough, and sometimes supplementation can provide useful support.
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