What you may have heard
Ketchup contains high fructose corn syrup and MSG for flavoring and sweetness.
What the science tells us
Numerous studies have shown that high fructose corn syrup is harmful to your health, increasing your risk of weight gain, type 2 diabetes, metabolic syndrome, and high triglyceride levels.
Excessive consumption of high fructose corn syrup is also linked to obesity and an increased risk of colon cancer (Goncalves et al.).
While MSG has not been shown to increase the risk of cancer, studies have linked MSG consumption to obesity, central nervous system disorders, liver damage, and reproductive malfunctions (Niaz et al.).
Laboratory Evidence/Supporting Evidence
One study conducted on mice studied the effects of high fructose corn syrup consumption. Researchers found that there was excess weight gain and the presence of tumors, indicating that fructose might affect tumor growth (NCI).
IARC Carcinogen Classification: Not classified
How to reduce your risk
Avoid products, including ketchup, that contain high fructose corn syrup and MSG. Eat ketchup in moderation to reduce your health risks.
Eating ketchup itself does not appear to cause cancer. However, high consumption of high fructose corn syrup, a key component in ketchup, is linked to obesity and an increased risk of colon cancer. While there are no direct links between cancer risk and MSG, there are other harmful health effects that should be considered when eating ketchup.
Learn More From These Trusted Sources
Mayo Clinic: High-fructose corn syrup and health concerns
Niaz et al.: Extensive use of monosodium glutamate: A threat to public health?
Mayo Clinic: Is MSG harmful?
Goncalves et al.: High-fructose corn syrup enhances intestinal tumor growth in mice
Published: July 7, 2021
Verified/updated: August 22, 2022