What to Do When Canola Oil Gives You Stomachaches
Health ConditionsDigestive Health

Why Do I Get a Stomachache After I Eat Canola Oil?

Why Do I Get a Stomachache After I Eat Canola Oil?
Everyday Health
By
Updated on August 28, 2025
by

Canola oil is one of the most widely used cooking oils. It’s also one of the healthiest oils to use for cooking because it’s low in saturated fat and high in unsaturated fat.

However, canola oil may cause stomachaches for several reasons.

Canola Oil Allergy

If eating canola oil gives you a stomachache, you may be allergic to it.

An allergic reaction occurs when your body produces an immune reaction that causes adverse effects to a food you consume, experts say.

These adverse effects can include hives, wheezing, and a hoarse voice. Other symptoms may include but are not limited to diarrhea, stomach cramps, and abdominal pain.

An allergic reaction is typically experienced within two hours of consuming the food.

Digestion of Fat

Canola oil, like all oils, is a high-fat substance. Some people experience difficulties digesting high-fat and fried foods, says Harvard Medical School.

If you eat a lot of foods fried in canola oil, you may get an upset stomach or diarrhea. Other gastrointestinal conditions, such as not having a gallbladder or chronic inflammation of the pancreas, can make some people less tolerant of fatty foods.

Tips

Keep a food diary for a couple of weeks. Record everything you consume, including beverages and medications. Note the times when you consume them. Then write down the times you experience stomach upset and other symptoms.

Take this diary to your healthcare provider to help them get a clearer picture of what your issue could be.

You could also completely abstain from canola oil for a set period to see whether the stomach upset subsides.

EDITORIAL SOURCES
Everyday Health follows strict sourcing guidelines to ensure the accuracy of its content, outlined in our editorial policy. We use only trustworthy sources, including peer-reviewed studies, board-certified medical experts, patients with lived experience, and information from top institutions.
Additional Sources
Meet Our Experts
See Our Editorial PolicyMeet Our Health Expert Network

Yuying Luo, MD

Medical Reviewer

Yuying Luo, MD, is an assistant professor of medicine at Mount Sinai West and Morningside in New York City. She aims to deliver evidence-based, patient-centered, and holistic care for her patients.

Her clinical and research focus includes patients with disorders of gut-brain interaction such as irritable bowel syndrome and functional dyspepsia; patients with lower gastrointestinal motility (constipation) disorders and defecatory and anorectal disorders (such as dyssynergic defecation); and women’s gastrointestinal health.

She graduated from Harvard with a bachelor's degree in molecular and cellular biology and received her MD from the NYU Grossman School of Medicine. She completed her residency in internal medicine at the Icahn School of Medicine at Mount Sinai, where she was also chief resident. She completed her gastroenterology fellowship at Mount Sinai Hospital and was also chief fellow.

See full bio

Raginee Edwards

Author

Raginee Edwards is a health and fitness writer whose work has been featured on the Livestrong Foundation and Demand Studios. She contributes practical health guidance on topics including digestive health and nutritional concerns.

See full bio
See Our Editorial PolicyMeet Our Health Expert Network