Weight loss surgery, such as gastric bypass, is becoming increasingly common as a treatment for obesity. However, such treatment may come with a health price tag.

Researchers at Wake Forest University have discovered that weight loss surgery can be linked to a condition called Wernicke's encephalopathy, in which the brain and nervous system don't get enough vitamin B1. The deficiency can lead to memory loss and vision problems.

In this study, the researchers found 32 cases of Wernicke's encephalopathy occurring after weight loss surgery. Many of these people had additional neurological symptoms like seizures, deafness, psychosis, muscle weakness and pain or numbness in the feet or hands. The complication seemed to be more common among those who had frequent vomiting after surgery and more commonly occurs one to three months after surgery. The researchers say that anyone experiencing neurological symptoms after weight loss surgery should seek help right away. Wernicke encephalopathy can be treated, if caught promptly, by injections of vitamin B1.

Source
Neurology 13th March 2007