It&#x27;s safe because it&#x27;s simply the salt of sodium and glutamic acid. Glutamate is an amino acid that is a fundamental building block of your metabolism. It&#x27;s also been omnipresent in human diets for millennia.<p>If we had discovered how to synthesize salt in 1909 and had called it &quot;NACL&quot; since then, it would be precisely as controversial as MSG is.