Waking up tired after a good night’s sleep? You may be deficient in this necessary vitamin

Waking up tired in the morning after a good night’s sleep could be a sign of vitamin B12 deficiency, according to new research.

The water-soluble vitamin, sourced from animal-derived foods or supplements, fights fatigue in addition to helping produce blood cells and supporting the nervous system. Low levels of the vitamin in the body hamper the vital processes.

A survey published in the British Journal of Nursing found that approximately 1,000 patients with B12 deficiency reported a wide range of symptoms - the most common being fatigue.

While 96 per cent of respondents said they experienced "unusual fatigue”, 86 per cent said they "wake up tired".

Fatigue is persistent tiredness despite having rest and with B12 deficiency, it could become more pronounced in the morning - waking up tired despite sleeping through the night.

Some 34 per cent of the respondents reported glossitis - swollen and inflamed tongue - while 30 per cent said they experienced a loss of hair, mouth ulcers or blurred vision.

However, many of the symptoms can be addressed with treatments. If left untreated, some problems can be irreversible. A delay in treatment increases the chance of permanent damage, according to experts.

The NHS says B12 deficiency can often be diagnosed by GPs based on symptoms and blood test results.

It can be addressed with two types of injections: hydroxocobalamin and cyanocobalamin.

"At first, you'll have these injections every other day for two weeks or until your symptoms have started improving," the NHS states.

"After this initial period, your treatment will depend on whether the cause of your vitamin B12 deficiency is related to your diet or whether the deficiency is causing any neurological problems, such as problems with thinking, memory and behaviour," says the state-funded health body.

The best sources of B12 are animal-based foods, including fish, meat and liver, clams, milk and dairy products and eggs, according to Nuneaton-based health food chain Holland and Barrett.