I developed acute migraine headaches and stomachaches, and no one ever suspected that a food additive was the trigger. MSG stimulates brain cell activity. It tricks your brain into thinking the food you are eating tastes good.
Manufacturers can and do use inferior ingredients and thus make the product seem tastier.
Inferior products and higher profits prevail at the expense of consumer health. MSG intolerance is not an allergic reaction, but a powerful drug reaction. Glutamate in the brain can be terribly destructive no matter where the grain glutamate comes from. The age or physical condition of a person is irrelevant. Large numbers of consumers have complained to the FDA that when they ingest MSG, they experience reactions ranging from such things as simple skin rash, flushing of the face, extreme tiredness, bloating, abdominal cramping, hyperactivity in children, migraine headache, asthma attacks, irregular or pounding heartbeat, loss of consciousness, severe depression.