Monosodium glutamate, or MSG, has been linked to a range of negative health issues, from headaches to obesity to cancer. Despite numerous headlines and claims, research on MSG in foods is murky at best. We set out to see whether MSG causes cancer or there’s more to the story. 

What Is Monosodium Glutamate In Food?

Monosodium glutamate is the sodium component of an amino acid called glutamic acid. Glutamic acid is a naturally occurring substance in the human body found in various foods, including cheese, soy products (mainly extracts) and tomatoes. MSG was originally used as a flavor enhancer in Japan and derived from seaweed. Contemporary MSB production utilizes a starch fermentation process instead of seaweed, following many of the same manufacturing steps as vinegar, wine, and yogurt. 

Does MSG Cause Cancer?

To date, there is no evidence linking monosodium glutamate and cancer. MSG cancer studies have been disappointingly flawed; preclinical research has associated MSG with a range of potential health problems, including:

  • Cardiotoxicity
  • Hepatotoxicity
  • Neurotoxicity
  • Low-grade inflammation
  • Metabolic issues
  • Behavioral changes

Comprehensive studies found serious methodological flaws in MSG studies, including researchers relying on tests conducted with excessive dosing. 

Other Alleged Dangers of MSG

The effect of monosodium glutamate on human health is far from established, however. There’s anecdotal evidence that MSG causes headaches and other issues in some individuals, a catalog of reactions so uniform that it’s called the MSG symptoms complex. These reactions include:

  • Headaches
  • Sweating
  • Feeling flush
  • Feeling pressure or numbness on the face
  • Irregular heart rate
  • Chest pain
  • Nausea 
  • Weakness

There is also growing evidence to classify MSG as a neurotoxin, although much of this work is focused entirely on rat populations, particularly those with obesity and diabetes.

Is MSG Safe to Eat?

Today, the US Food and Drug Association (FDA) categorizes monosodium glutamate as generally recognized as safe (GRAS). Unlike some other GRAS food additives, the FDA does require all products containing MSG to include the ingredient to be listed on the label. Most experts recommend avoiding MSB intake if you experience any reactions or discomfort when ingesting MSG. The use of MSG in consumer food products has declined over the years due to health concerns, but it is still found in many ultraprocessed foods, including:

  • Lunch meat/hot dogs
  • Salad dressing
  • Ketchup
  • Seasoning blends
  • Instant noodles and soups

Check the label to see if your favorite foods contain MSG. 

More Information Leads to Less Cancer

While there’s little evidence that MSG causes cancer, it’s one of many ingredients that require additional research and testing. Less Cancer is committed to lowering cancer rates through advocacy, education, and programming. Support our work today by making a tax-deductible donation and prioritizing prevention.