Some people must avoid foods high in msg, as oversupply of the neurotransmitter can over stimulate the brain, inducing seizures or migraines.

The right answer is glutamate

Glutamate is a major excitatory neurotransmitter associated with learning and memory.

It is also associated with Alzheimer's disease whose first symptoms are felt in memory.

Most people unknowingly consume monosodium glutamate (MSG), a commonly used food additive.

An experiment was done on healthy patients, giving them 12 grams of glutamate. It was found that the experience led to headaches, nausea or jaw pain in 50-60% of cases.

It was also measured the level of glutamate contained in the muscles of patients with jaw problems. The tests concluded that the most painful muscles were those containing the highest levels of glutamate.

According to him, one of the keys to chronic pain could lie in the development of drugs that reduce the rate of glutamate.