Include more vitamin B1-rich food in your diet as neurologists have underlined that deficiency of a single vitamin B1 (or thiamine) can cause a potentially fatal brain disorder.

The brain disorder called Wernicke encephalopathy typically occurs in people who have disorders such as alcoholism and anorexia that lead to malnourishment.

"Wernicke encephalopathy is an example of the wide range of brain diseases called encephalopathies that are caused by metabolic disorders and toxic substances," said Matthew McCoyd, a neurologist at Loyola University Medical Center in the US.

Untreated, the condition can lead to irreversible brain damage and death, the researchers said.

Symptoms of the disorder can include confusion, hallucinations, coma, loss of muscle coordination and vision problems such as double vision and involuntary eye movements.

"Toxic and metabolic encephalopathies may range in severity from the acute confusional state to frank coma," McCoyd added.

Wernicke encephalopathy is a medical emergency that requires immediate thiamine treatment either by injection or IV.

"In the absence of treatment, deficiency can lead to irreversible brain damage and death with an estimated mortality of 20 percent," the Loyola neurologists wrote.

Vitamin B1 is found in a wide variety of foods including watermelon, cereal grains, oatmeal, potatoes and eggs.

The report appeared in the journal Scientific American Medicine.