Vitamin B12 – how it affects your body and how to know if you’re deficient
What is vitamin B12
Also known as cobalamin, vitamin B12 is an important water-soluble vitamin needed for the production of red blood cells, repairing body tissues, and the proper functioning of the nervous system. Our body can’t produce B12, so we need to get it from our diet.
It’s primarily naturally found in animal-based foods such as meat, fish, poultry, eggs and dairy, although some foods are fortified with B12. Because vitamin B12 is not found in plants, people who follow vegetarian/vegan diets are at risk of deficiency. B12 deficiency is also common in the elderly.
Why is vitamin B12 important?
It is vital for a number of functions in your body, namely red blood cell formation, normal nerve function, and DNA synthesis (duplicating DNA when cells divide). It’s also needed during pregnancy and breastfeeding.
What happens if I don’t have enough?
Vitamin B12 deficiency is a serious health problem that can lead to a number of health complications. These include:
- Anaemia — not enough red blood cells in your blood
- Neuropathy — nerve damage
- Neurological disorders — ranging from minor behaviour changes to severe neurodegenerative disorders.
What causes vitamin B12 deficiency?
Vitamin B12 deficiency can be caused by a number of factors. However, the two most common are vegetarian/vegan diets, and an inability to absorb vitamin B12.
As vitamin B12 isn’t found in plant foods, strict vegetarians and vegans are at high risk of deficiency, especially if they don’t eat foods fortified with the vitamin, or don’t use a supplement.
People with conditions that affect nutrient absorption are also at risk. Even if they eat enough foods containing vitamin B12, if their body can’t absorb this vitamin, they may become deficient. Common conditions that interfere with nutrient absorption are coeliac disease and Crohn’s disease.
How do I know if I’m deficient?
Vitamin B12 deficiency can develop slowly over time and diagnosis can be complex. It’s often mistaken for a folate deficiency, as folate levels also drop when you’re lacking vitamin B12.
Symptoms of B12 deficiency can be confused with other conditions, which is why diagnosis can take time. Typical symptoms include:
- strange sensations, numbness, or tingling in the hands, legs, or feet
- difficulty walking (staggering, balance problems)
- tiredness, fatigue and weakness
- light-headedness and breathlessness
- pale, jaundiced skin
- rapid heart rate
- bruising or bleeding easily
- disturbed vision
- upset bowel
- a swollen, inflamed tongue and mouth ulcers
- high temperature
- difficulty thinking and reasoning, or memory loss
- changes in mood.
Who is at risk of deficiency?
As we’ve already mentioned people who don’t eat animal products, or have nutrient absorption problems are at risk of a B12 deficiency. Others at risk include:
- The elderly — reduced levels of enzymes that break down protein, and reduced levels of stomach acid mean that B12 absorption is compromised in older people. According to Harvard University, up to 20 per cent of people over 50 may have a vitamin B12 deficiency.
- People who’ve had bowel surgery which removed the part that absorbs B12
- People taking certain diabetes medications
- Those taking long-term antacid drugs for heartburn.
Best sources of vitamin B12
The best sources are animal products including red meat, poultry, seafood, eggs and milk. Foods fortified with B12 that are available include some soy milks, yeast spread and vegetarian meat substitutes, including soy-based burgers and sausages.
What about supplements?
It’s recommended that those who can’t consume or absorb enough B12 through their diet should use supplements. This is particularly important for pregnant or breastfeeding women. However, make sure you speak to your doctor first. Your doctor will be able to order a blood test to check levels of B12 in your body.
In some cases, it may be necessary to receive B12 injections, which are generally considered to be very safe with no major side effects. Of course, some people may experience side effects associated with allergic reactions or sensitivity, so make sure you discuss this fully with your doctor.
Should you require the addition of vitamins or supplements to your diet, you can shop a full range of supplements here.
Please note: The information supplied is general in nature. Please consult your medical practitioner for individual advice.
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