Who Needs MSG?

MSG — monosodium glutamate — is an old processed food villain that flashed across the screen in a commentary just published in the Journal of Medicinal Foods. The commentary raises a question in its title: “How safe is monosodium glutamate? Exploring the link to obesity, metabolic disorders, and inflammatory disease.” Satisfactory answers are tough to find.

Digging through the evidence on MSG is spectacularly unsatisfying — like pulling a loose thread on a sweater. FDA has a FAQ that essentially tells us it’s everywhere and nobody’s pinned any safety issues on it yet. That FAQ is an artifact of an old battle over the safety of MSG. An expert analysis by the Federation of Societies for Experimental Biology (FASEB) in 1995 concluded that MSG is safe when “eaten at customary levels” although there may be a subgroup of sensitive but otherwise healthy individuals who react badly to food with MSG.

But abundant animal research links MSG to triggering obesity. In fact, MSG-induced obesity is an animal model used for the study of obesity interventions. A study in the American Journal of Clinical Nutrition found a significant association between MSG consumption and excess weight in Chinese adults. Of course, cause and effect remains to be proven. We wonder if anyone will garner the resources to do a real experiment on this presumed safe food ingredient to settle the question.

Glutamate is naturally abundant in food we routinely eat. It’s responsible for the umami flavor that makes us crave savory foods like cheeses and cured meats. We first encounter umami in breast milk. Because glutamate confers a savory flavor we crave, it’s one of the most widely used additives in our food supply. Those Nacho Cheese Doritos use MSG blended with other flavors to fuel a craving that some people cannot resist.

MSG makes its way into processed food under many different labels: spices and flavoring, yeast extract, soy extract, protein isolate. Legally, though, processed foods with any ingredients that naturally contain MSG are barred from putting the words “No MSG” on their label. 

Glutamate is not essential. You’ll likely get it in natural whole foods. But adding it is a shortcut for people who want to sell you more processed foods. You can live quite well — arguably better — without any MSG added to the food you eat.

Click here to read the commentary in the Journal of Medicinal Foods. Click here for the study in the American Journal of Clinical Nutrition. Click here for FDA’s FAQ on MSG. Click here and here for more background on MSG.

Umami, photograph © Pewari / flickr

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