Fatigue, lack of energy, pale skin, changes in mood… you might think that these sorts of things are unavoidable side-effects of the change in season – especially as the nights draw in and the mercury drops. But it’s possible that a deficiency in vitamin B12 could be the underlying cause.
Naturally found in animal-based foods, including meat, fish, eggs, milk and cheese, vitamin B12 is crucial to support an array of vital systems in the body – circulation, brain health and cell regeneration, to name a few. Since some people – most often vegetarians and vegans – don’t get enough of these foods, a good quality vitamin B12 supplement can be helpful as part of a healthy, balanced lifestyle.
Here, takes a deep dive into vitamin B12 and its benefits.
Why it’s -approved: Viridian Liquid B12 is an orange-flavoured, vegan formulation providing two active forms of vitamin B12: methylcobalamin and adenosylcobalamin, each supporting different metabolic pathways in the body. A daily dose of 0.5 ml, taken once or twice daily, delivers 500 mg of vitamin B12, supporting energy production, nervous system function and overall vitality.
Why it’s -approved: For fast absorption, BetterYou’s easy-to-use spray provides methylcobalamin in a convenient format designed for quick uptake. It supports energy, focus and nervous system health, and is simple to use at home or on the go. Use four sprays into the cheek.
Why it’s -approved: Each 1ml serving of Pure Encapsulations’ vitamin B12 supplement provides 1,000mg of bioavailable methylcobalamin, helping to reduce fatigue while supporting a healthy nervous system and immune function.
Why it’s -approved: Formulated with 2,500mg of liposomal methylcobalamin per serving, Zooki Vitamin B12 capsules are designed to support optimal absorption while contributing to energy levels, cognitive function and immune health.
Why it’s -approved: This formula contains methylcobalamin and deoxyadenosylcobalamin to support energy levels, nervous system health and mental wellbeing. It may be particularly helpful for those experiencing fatigue, low energy or for individuals following a vegetarian or vegan diet.
What does vitamin B12 do for the body?
Belle Amatt, a nutritionist at W-Wellness, says: “It’s vital for red blood cell formation, DNA synthesis and maintaining the myelin sheath, which protects nerve and brain function.” It also plays an important role in brain and cardiovascular health, helps support healthy hair, skin and nails, and is imperative for immunity, which is especially important in the colder months when respiratory illnesses like colds and flu become more common.
Functional medicine doctor and GP Dr Nirusha Kumaran adds: “Beyond preventing fatigue and anaemia, B12 plays a central role in methylation, a fundamental biochemical process that switches genes on and off, supports detoxification, regulates mood and hormones, and maintains healthy DNA.”
Vitamin B12 also helps to regulate an amino acid called homocysteine, which at elevated levels can damage blood vessels by increasing oxidative stress and inflammation. The result? A higher chance of cardiovascular disease. “Chronically high homocysteine is linked to an increased risk of blood clots, heart attacks, strokes, cognitive decline and pregnancy complications,” she adds, but maintaining good levels of B12, not to mention folate and vitamin B6, can help keep homocysteine in check, says Dr Kumaran, further protecting heart and brain health.
What are the symptoms of vitamin B12 deficiency?
“A key reason vitamin B12 deficiency occurs is that its absorption depends on two factors: a sufficiently acidic stomach environment and a protein called intrinsic factor, which binds to B12 and helps transport it through the gut for absorption,” says Amatt. “As we age, the stomach naturally produces less hydrochloric acid, which can reduce how effectively B12 is absorbed.”
Stomach acidity can also be reduced by chronic stress, certain digestive medications and bacterial infections. Together, these factors can significantly impair absorption of this essential nutrient. “Those following a vegan diet are also at increased risk, as plant-based foods contain very few absorbable sources of B12,” Amatt adds.
Common symptoms of vitamin B12 deficiency include:
- Low mood
- Poor concentration
- Pale skin
- Tingling or numbness in the hands and feet
- Unsteady balance
Rather than self-diagnosing a vitamin B12 deficiency based on the various symptoms, requesting a standard blood test from your GP can help determine whether you might need a supplement.
What foods are rich in vitamin B12?
The richest food sources of vitamin B12 include fish, shellfish, meat, poultry, eggs and dairy products – and it is always best to start with a balanced diet before considering supplementation. “Fortified plant milks [including soy, oat, almond and coconut], nutritional yeast and B12-fortified cereals can also help support intake for vegans and vegetarians,” says Dr Kumaran, “Although they are unlikely to be sufficient on their own to meet requirements.”
What should you look for in a vitamin B12 supplement?
Dr Kumaran recommends choosing an active, bioavailable form of B12. “Methylcobalamin or adenosylcobalamin [are types] which the body can use directly,” says Dr Kumaran – but not all supplements are created equal. “Avoid cyanocobalamin, a synthetic form that must be converted and releases a small amount of cyanide as a by-product.”
Daily requirements are relatively small – around 2.4mg for adults – but supplements typically contain much higher doses (often between 50 and 1,000mg) to help overcome limited absorption. “For best results, I recommend sublingual tablets [those that dissolve under the tongue], sprays or lozenges that absorb through the oral mucous membranes, particularly for those with digestive issues,” says Dr Kumaran.
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