The MSG debate is back

Gwyneth famously quipped that she’d “rather die than let her kids eat Cup-a-Soup.” We’re guessing the MSG content was high on her list of offending ingredients. The food additive has sparked controversy among scientists, nutritionists and the general public for years, causing many health-conscious eaters to navigate their way around MSG, while chefs like Momofuku’s David Chang favor it—both as modern-day invention and flavor enhancer. As MSG re-enters the cultural conversation, the question remains: To eat it or not?

What It (Really) Is: MSG, a.k.a. monosodium glutamate, is a flavor enhancer. Glutamate exists naturally in certain foods and in the brain, but MSG, which is a sodium ion bonded to glutamate, is not naturally occurring. It’s a processed additive, a man-made invention that dates back to 1908 when it was derived from seaweed. Today, it’s created from starch or sugar.

How It’s Used:While MSG is credited with having an umami taste, it more accurately conveys that taste only when mixed with other savory flavors. On it’s own, it doesn’t taste great, but combined properly, it can make food taste even better, stimulating your appetite—hence food manufacturers use it to spike soups, salad dressings, sauces, meats and myriad snack foods.

Why It’s Controversial: For those sensitive to it, MSG has been associated with headaches, flushing, sweating, anxiety, rapid heartbeat, and other symptoms commonly (and not so cleverly) referred to as “MSG symptom complex.” The Food and Drug Administration and The World Health Organization approve its use, but new research continues to call MSG’s safety into question. Here, Ryan Andrews, a fitness and nutrition coach with Precision Nutrition, and Haylie Pomroy, nutritionist and creator of The Fast Metabolism Diet, join the debate.

Pomroy’s Stance: Avoid it at all costs.

1) “MSG inhibits the brain’s receptor sites for leptin, the satiety hormone, so your brain doesn’t get the message that it’s full when you’re consuming it,” says Pomroy. “This can negatively impact metabolism, because when leptin uptake is good, your body burns fat more easily. The speculation is that MSG can lead to leptin resistance.”

2) A new study in the Journal of Cellular and Molecular Medicine found that in male rats, MSG elevated obesity and inhibited the breaking down of fat, notes Pomroy. And in another paper published at the beginning the year, rats that were made obese using MSG showed insulin resistance as well as elevated LDL (bad) cholesterol and triglycerides.

Andrews’s Stance: If you’re not sensitive, it’s fine in moderation.

1) “MSG is generally regarded as safe, but it’s a dicey subject because so is aspartame, which I don’t think is healthy to consume on a regular basis,” says Andrews. “MSG isn’t something I’d recommend as a part of your everyday diet, but if you’re not sensitive to it, it may not harm you. It can hide under a variety of names on ingredient labels including hydrolyzed vegetable protein and other types of protein isolates, so it’s possible that you may already be consuming it and not reacting negatively."

2) “If a chef is preparing nutritious vegetables or a dish you may not normally try and adding some MSG to bring out different flavors, then that may be a worthwhile nutritional trade-off for you,” says Andrews.