Vitamin B12 is a critical nutrient for the biological process, and if a deficiency was left untreated it could become serious.
Common symptoms include fatigue, pins and needles, and weight loss.
Surprisingly, it can also occasionally cause three changes in your nails, The Express reports.
Read More: Vitamin B12 deficiency warning signs of low levels inside your mouth
If your fingernails start to turn brittle, discolour, or streak, the Journal of Family Practice suggests that you visit your doctor.
Researchers state that such changes in the appearance of nails could be resolved with adequate B12 supplementation.
These issues typically arise as the red blood count falls, which prevents the tissues and organs from carrying out their job properly.
A Case Report published in BMJ in 2018, blue-black pigmentation and darkened streaks could both be hinting at an underlying deficiency in B12.
The authors stated: “Nail changes in vitamin B12 deficiency present as hyperpigmentation of nails like bluish discolouration of nails, blue-black pigmentation with dark longitudinal streaks and longitudinal and reticulate darkened streaks.
“The nail pigmentation associated with B12 deficiency is more frequent in patients with dark skin.
“Complications of vitamin B12 may be prevented may be prevented if the condition is recognized early and treatment is initiated.”
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Overall adequate nutrition should help stave off any nutritional deficiency, but some individuals become increasingly susceptible to low B12 levels as they age.
Risk factors for a deficiency can include a reduction in intrinsic factor, which is produced in the stomach and is needed for the absorption of vitamin B12.
Practices taken to improve health, such as weight loss surgery and vegetarianism are also known causes of B12 deficiency.
When B12 is stored in the liver, it can sustain the body’s needs for years, so symptoms of a deficiency will generally appear gradually.
The NHS explains: “Vitamin B12 or folate deficiency can cause a wide range of symptoms.
“These usually develop gradually, but can worsen if the condition goes untreated.”
In the advanced stages of a deficiency, the nerve endings could become damaged, giving rise to peripheral neuropathy.
This is because myelin production ceases – which is a coating that forms around the nerves and enables the transmission of electrical impulses.
A decline in mental abilities may become evidence, as well as pins and needles in the extremities.
Patients may also notice changes in the way they walk around, as well as changes in the way they think, feel and behave.
The recommended daily amount of vitamin B12 for adults is 2.4 micrograms, according to the Mayo Clinic.
Larger doses have been found to be safe, however, as the body absorbs what it needs before passing out the excess through the urine.
Those with a severe deficiency, or an inability to absorb B12 naturally, may be recommended injections at regular intervals.
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