Vitamin B12 is an essential nutrient for the formation of red blood cells, for neurological function and for the making of DNA. In most people, eating a varied diet, obtaining enough B12 is not difficult. However, people following a plant based or vegan diet with no animal products, it is likely to be deficient. The same may apply to those with certain medical conditions, the elderly and those who have had gastric band surgery. All these groups may need to have their B12 levels tested and if necessary take supplements.
A deficiency in B12 can lead to anaemia, psychiatric and neurological symptoms.
All the good sources of vitamin B12 are animal products. Some examples are canned tuna, salmon, eggs, liver, beef, trout, clams, low fat yoghurt and milk, chicken breast and ham. It’s easy to see why vegans struggle to get enough B12 in their diet!
Various blogs and vegan websites suggest that seaweed, spirulina, barley grass and raw foods can provide adequate B12 for vegans. This is rarely the case. Even where the amount of B12 in the food is adequate, the bioavailability is low (ie the body cannot absorb it well).
A supplemental form of B12 needn’t be a pill. Plenty of foods are fortified with vitamin B12. Examples of some are:
· plant milks (soy, almond, oat, cashew or coconut milk)
· Some breakfast cereals
· Some margarines and spreads
· Nutritional yeast (used to add a cheesy flavour)
· Tofu
· Some fruit juice
· Non-dairy yoghurts.
These foods are not necessarily fortified, so check the label.
Some studies have suggested that even moderate alcohol intake can decrease B12 levels in the body and alcohol-related liver disease can lead to falsely elevated B12 test levelsand so mask a deficiency.
Another nutrient which if consumed (or supplemented) in excess can mask a B12 deficiency is folate. Folic acid supplements are advised for women planning, or in the early stages of, pregnancy as it is essential for the baby’s brain stem development. However, if folate intake is chronically higher than B12 intake it can not only mask a B12 deficiency but also worsen the adverse effects such as lack of balance and confusion, blurred vision or mood changes such as seen in dementia or depression. It is easy to see how these could be put down to old age when in fact it may be a nutritional issue.
In Australia the recommended daily intake of vitamin B12 for adults of any age is 2.4 µg/day.
If you eat a varied diet and are in good health then a B12 deficiency is very unlikely. However, if you eat no or few animal products then asking your doctor for a test to check your levels is a good idea.