Food additives have been used for years to flavor, preserve, thicken, and color foods. But while our eyes and palettes may be well satisfied, Federal Regulations require evidence that additives are safe, and MSG, a popular additive made notorious by Chinese take-out, is under infamously close scrutiny.

The Good, The Bad, And The Flavorful – What It Is

The U.S. Food and Drug Administration (FDA) defines a flavor enhancer as any compound used to provide a “technical effect” in foods by augmenting the taste already present.

MSG is made from hydrolyzed vegetable protein, which comes from “junk” vegetables that are no longer fit for sale. The process involves boiling these vegetables in a vat of acid, followed by neutralizing caustic soda. The result is a brown sludge that collects on top, which is scraped off, dried, and then becomes a powder that is sprinkled into that bag of Doritos. Appetizing, right?

Its claim to fame might be cheap Chinese food, but it can also be found in chips and dips, pre-made soups, frozen meals, instant noodles, spice blends, ketchup, mayonnaise, granola bars, fruit snacks and candy, lunchmeats, frozen hamburgers, bacon, ham, and canned tuna fish. Restaurants also use MSG in some of their meat products. Even snacks considered healthy, such as yogurt and cottage cheese, may include it. Given how many products use MSG, it’s indeed relevant to our health!

The FDA states there is no evidence that MSG is a super villain contributing to long-term health problemsConsensus meeting: monosodium glutamate – an update. Beyreuther K., Biesalski HK., Fernstrom JD., et al. ZMBH, University of Heidelberg, Germany. European Journal if Clinical Nutrition 2007 Mar;61(3):304-13.. However, they acknowledge that some people may have short-term reactions, including headaches, heart palpitations, shortness of breath, nausea, sweating, and numbness or tingling around the mouth in responseReview of alleged reaction to monosodium glutamate and outcome of a multicenter double-blind placebo-controlled study. Geha RS., Beiser A., Ren C., et al. Division of Immunology, Children’s Hospital and Department of Pediatrics, Harvard University, Boston, MA, USA. Journal of Nutrition 2000 Apr;130(4S Suppl):1058S-62S., which hardly seems like a good time, either.

But short-term, temporary side effects aside, why such the bad rap? Well, MSG has been shown in lab tests to affect the regulation of hypothalamic appetite suppression (read: it makes you feel hungry again), which links it to obesity and type 2 diabetesMonosodium glutamate (MSG): a villain and promoter of liver inflammation and dysplasia. Nakanishi Y., Tsuneyama K., Fujimoto M., et al. Department of Diagnostic Pathology, Graduate School of Medicine and Pharmaceutical Sciences, University of Toyama, Toyama, Japan. Journal of Autoimmunity 2008 Feb-Mar;30(1-2):42-50.. Glutamate (MSG’s “G” namesake), which is considered an excitotoxin, can activate neurons and large enough doses can cause these cells to be excited to death, linking MSG to a more serious problem: brain damageExcitotoxic damage to white matter. Matute C., Alberdi E., Domercq M., et al. Departamento de Neurociencias, Universidad del País Vasco, Zamudio, Spain. Journal of Anatomy 2007 Jun;210(6):693-702..

Who’s Down With MSG? No-bo-dy. – What It Means

So who is right? According to the Food and Drug Administration, the World Health Organization, and the Food and Agriculture Organization of the United Nations, MSG is a safe, naturally occurring food ingredient, and the controversy only arises from anecdotal complaints. However, other tests beg to differ. Lab tests contend that it causes obesity, disease, and possibly brain damage. To be safe, avoid it all together, but don’t stress out too much if it slips in there haphazardly!

Certainty Level

MSG is definitely dangerous to your health… at least if you’re a rat.