Around one-in-four people may have a vitamin B12 deficiency.
Pale skin or skin with a slight yellow tinge can be a sign of vitamin B12 deficiency.
The body uses vitamin B12 to make red blood cells and to keep the nervous system healthy.
Without enough B12 the blood cells produced are too large and cannot move into the bloodstream, leading to pale skin.
Around one-quarter of people may have a vitamin B12 deficiency.
Other, more common signs of vitamin B12 deficiency include feeling tired, experiencing muscle weakness and being constipated.
People experiencing a mood disorder, like depression, can also be deficient in vitamin B12.
People who may have difficulty getting enough vitamin B12 include vegetarians, older people and those with some digestive disorders, such as Crohn’s disease.
Some medications, such as those to treat ulcers and excessive stomach acid, are also linked to vitamin B12 deficiency.
One study of 25,956 patients diagnosed with a vitamin B12 deficiency found that the condition was linked to taking anti-acid medications.
The study’s authors write:
“Vitamin B12 deficiency is relatively common, especially among older adults; it has potentially serious medical complications if undiagnosed.
Left untreated, vitamin B12 deficiency can lead to dementia, neurologic damage, anemia, and other complications, which may be irreversible.”
Vitamin B12 deficiency is easy to rectify with supplements or by dietary changes.
Vitamin B12 levels can be boosted through supplementation or by eating foods such as dairy, liver, salmon and eggs.
Other good sources of vitamin B12 include poultry and low-fat milk.
Fortified breakfast cereals also contain vitamin B12.
The study was published in JAMA (Lam et al., 2013).