If you’ve ever felt like your energy’s just not what it used to be or if you’ve found yourself struggling with concentration, mood changes, or tingling in your hands or feet, there’s a chance your body could be running low on a surprisingly common but often overlooked nutrient – Vitamin B12.
Vitamin B12 is essential in processes involved in keeping your brain sharp, your nervous system functioning smoothly, and your energy levels steady. Despite its critical role in important daily functions, many adults, especially those over 50 or following plant-based diets, simply aren’t getting enough of it. In this article, we’ll take a look at the importance of B12 to all of these functions, who is most at risk of deficiency, how to identify signs of low B12, and the best sources of B12 from diet and supplements (because form matters!).
Why Do We Need Vitamin B12?
Vitamin B12 is a water-soluble vitamin, which means it needs to be replaced daily.
It’s a crucial nutrient for a range of physiological processes - the body uses it to:
- Produce red blood cells, which carry oxygen throughout the body
- Maintain healthy nerve function, helping support balance, reflexes, and coordination
- Support neurological health, including cognition, memory, and mood regulation 1
- Assist in DNA synthesis, cell division, and repair 2
- Convert carbohydrates, fats, and proteins into usable cellular energy 3
B12 is a multitasking nutrient that affects how you think, feel, and function. Without it, your body struggles to perform even basic cellular tasks efficiently.
How B12 Works and Why Absorption is Key
Once ingested, B12 binds to intrinsic factor – a protein produced in the stomach that is essential for B12 absorption in the small intestine. From there, it enters the bloodstream and is delivered to tissues, especially those with high metabolic demands like the brain, liver, and bone marrow.
B12 absorption depends on a well-functioning digestive system. Conditions like low stomach acid (which becomes more common with age), gastrointestinal inflammation, and even certain medications can impair your body’s ability to take in and use B12 effectively.
That’s why even if your diet includes B12-rich foods, you may still be running low, particularly if you’re over 50 or have gut health issues.
B12 Forms: What’s the Difference and Does it Matter?
B12 supplements are not a one-size-fits-all. Here’s a quick rundown on the main forms typically found in supplements:
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Cyanocobalamin is a synthetic form of B12 that needs to be converted by the body into its active forms methylcobalamin and adenosylcobalamin before it can be used. While it's cost-effective, the conversion isn’t always efficient, especially in people with genetic or metabolic impairments.
- Methylcobalamin (also called mecobalamin) is the active, bioavailable form of B12. It bypasses the conversion step and is ready for immediate use by the body, particularly in the nervous system and brain.4
Choosing a B12 supplement that contains methylcobalamin means your body doesn’t have to work as hard to make use of it, resulting in faster, more efficient support for energy, cognition, and neurological function.
Populations at Higher Risk of Vitamin B12 Deficiency
Some groups are more prone to developing B12 deficiency due to limited intake, absorption issues, or increased physiological demand.
Groups at risk of B12 deficiency include:
- Vegans and vegetarians, since B12 is almost exclusively found in animal-based foods
- Adults over 50, due to reduced stomach acid production (which affects absorption)
- People with gastrointestinal conditions, such as coeliac disease, Crohn’s disease, or gastritis
- Individuals on long-term medications, including antacids, proton pump inhibitors, metformin, or the oral contraceptive pill 5
- People under high or prolonged stress, which may increase nutrient turnover and deplete stores
How to know if You’re Low in B12
Vitamin B12 deficiency can develop gradually and go unnoticed until symptoms become more pronounced. Early signs and symptoms can include:
- Persistent fatigue or weakness
- Poor concentration and memory lapses ("brain fog")
- Numbness or tingling in the hands or feet
- Mood changes, irritability, or low mood
- Pale or jaundiced skin
- Dizziness or shortness of breath
- Glossitis (inflamed or sore tongue)
If left untreated, B12 deficiency can lead to irreversible nerve damage, so early detection and correction are important.
Dietary Sources of Vitamin B12
Vitamin B12 is naturally present in animal-derived foods, including:
- Beef, lamb, and poultry
- Fish and shellfish (like salmon, tuna, and clams)
- Eggs and dairy products
- Fortified plant-based milks, cereals, or nutritional yeast (for vegans – check the label)
While a well-rounded diet can provide enough B12 for many, certain life stages or health conditions may increase your need—and that’s where targeted supplementation can help.
Supporting B12 Levels Through Supplementation
Even with a nutritious diet, modern lifestyles, ageing, and digestive challenges can impact how much B12 your body actually absorbs and uses.
This is where Micronutrition’s LipoCap™ B12 comes in.
Formulated with methylcobalamin, the active, bioavailable form, and delivered in a liposomal capsule for enhanced absorption, LipoCap™ B12 helps ensure your body gets the B12 it needs for:
- Daily energy production
- Clearer thinking and mental sharpness
- Nervous system support
- Red blood cell health
Vitamin B12 isn’t just a nice-to-have nutrient, it’s essential for daily function and long-term health. From energy to immunity, brain function to red blood cell production, it plays a critical role in keeping you energised, sharp, and resilient as you age. With the right form of B12, delivered in a supplement designed for optimal absorption, you can feel confident the B12 supplement you take is being properly absorbed.
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This article was written by Sophia Power, a Clinical Nutritionist.
References:
- NIH. Vitamin B12-deficiency anemia. Updated March 2022, accessed May 2025 from https://www.nhlbi.nih.gov/health/anemia/vitamin-b12-deficiency-anemia
- Rzepka, Z., et al. (2021). Response of human glioblastoma cells to vitamin B12 deficiency: a study using the non-toxic cobalamin antagonist. Biology (Basel), 10(1):69. https://pmc.ncbi.nlm.nih.gov/articles/PMC7835758/
- NIH. Vitamin B12 fact sheet for health professionals. Updated March 2024, accessed May 2025 from https://ods.od.nih.gov/factsheets/VitaminB12-HealthProfessional/
- Froese, D.S., et al. (2010). Genetic disorders of vitamin B12 metabolism: eight complementation groups - eight genes. Expert Rev Mol Med, 12:37. https://pmc.ncbi.nlm.nih.gov/articles/PMC2995210/
- Evidence-based medicine consult. Medications known to decrease vitamin B12 levels. Reviewed October 2015, accessed May 2025 from https://www.ebmconsult.com/articles/vitamin-b12-medication-interactions-lower-levels