Three early warning signs of 'serious' vitamin deficiency that can cause paranoia and delusion

When your body is not getting the right amount of nutrients and vitamins, your health will start to suffer. However, one vitamin deficiency can pose a greater risk to your long-term health than others, resulting in damaging and sometimes permanent symptoms like mental disorders, infertility, and nerve damage.

The vitamin B12 is not as well known as other nutrients but is necessary for key bodily functions, including parts of your metabolism, and nervous and circulatory systems. Due to its widespread use throughout the body, when these functions stop receiving enough B12, it can cause serious problems, from chronic fatigue to paranoia and delusions.

Typical causes of the deficiency are usually either biological through a form of anaemia, or dietary from eating a vegan or plant-based diet. NHS England has said it is "important" to spot the early warning signs of this deficiency, as it can cause permanent and "irreversible" damage if left untreated.

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Most of the deficiencies are caused by your stomach being unable to process B12 due to some other condition, such as different forms of anaemia. In rarer cases, people who do not eat products containing B12, like fish and eggs, can develop the symptoms of B12 deficiency, though this can be avoided by taking multivitamins.

Unlike the symptoms of other vitamin deficiencies, the symptoms that your body is lacking B12 often include sudden or even gradual changes in your mental health or personality, sometimes causing serious symptoms like paranoia that have to be treated right away. Studies suggest that these neuropathic symptoms are more likely in older people, but can affect people of all ages.

Three early warning signs that you are lacking B12

While there are several physical symptoms of a B12 deficiency, research suggests that the most common way it is presented by a patient at a doctor's surgery is neurological and psychiatric. This means symptoms that are not real in a physical sense, but conjured up by your brain as your brain and nervous system start to lose function.

Among the most common neurological symptoms is paraesthesia, a condition where you develop burning, pricking, or itching sensations in different parts of your body. This can feel like pins and needles, which is usually caused by blood flow issues, but in this case is a manifestation that your nervous system is struggling.

People lacking this vitamin can also experience ataxia, where their finer speech and motor skills start to decline. Patients will notice this when writing, trying to maintain their balance, or if their speech begins to slur - if not confused with another condition, this can be a key sign that your body is no longer processing B12.

The other and most concerning presentation of the deficiency is, what scientists refer to as, "delirium." This is the decline of your higher cognitive function as a result of key processes in your brain shutting down without the necessary B12.

This delirium can manifest as paranoid thoughts of persecution, disorganised thought patterns, or auditory and visual hallucinations. If you are experiencing any of these symptoms, speak to your GP. Though these symptoms are serious, if you catch them early, they could all be cured with a simple injection.

Other possible symptoms of B12 deficiency

Whatever the cause of the B12 deficiency, many of the symptoms are the same. However, due to the variety and gradual onset of these B12 deficiency warning signs, they can be easy to dismiss or confuse with other conditions.

The NHS lists the general symptoms of this nutrient deficiency as:

• Rapid breathing or shortness of breath

• Headaches

• Indigestion

• Loss of appetite

• Palpitations

• Problems with your vision

• Feeling weak or tired

• Diarrhoea

• Sore or red tongue, sometimes with mouth ulcers

• Problems with memory, understanding and judgment

If you are concerned that you may have a B12 deficiency, speak to your GP and they will conduct a blood test. As most cases are caused by an underlying problem resulting in your body not processing B12, the treatment typically involves a series of B12 injections administered by your GP.