Nutrients
Vitamin B12
Also known as: cobalamin, B12
What it is
Vitamin B12 is needed to make red blood cells and maintain the nervous system. It comes mainly from animal foods, so intake can be lower on vegan or vegetarian diets.
Why it matters
Low B12 can cause fatigue, anaemia and neurological symptoms, and it interacts with folate and homocysteine metabolism. It is a modifiable marker that is easy to check.
What “optimal” looks like
A healthy sufficiency range applies; interpretation can be nuanced because blood B12 doesn’t always reflect tissue status. Your clinician may look at related markers if a result is borderline.
This is general information, not medical advice or a diagnosis. Always discuss your results with a qualified clinician.
Related
See your own Vitamin B12
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