The Hidden Dangers of Seed Oils

The Truth About Seed Oils: How They’re Made and Why They’re Harmful

Seed oils are in nearly everything—from your favorite snacks to most restaurant meals. They’re marketed as “healthy,” but the reality is that these oils can harm your body in ways that aren’t immediately obvious. Even sesame seed oil, which has been used for centuries, carries hidden risks that make it a poor choice for regular use.

What Are Seed Oils?

Seed oils, also called vegetable oils, are made from seeds like:

• Soybeans

• Corn

• Canola (rapeseed)

• Sunflowers

• Cottonseed

• Sesame seeds

These oils are found in packaged foods, fried dishes, salad dressings, and even so-called “health” foods.

Unlike natural fats like olive oil or butter, seed oils require extensive processing to make them edible. The seeds are crushed and heated to extract the oil, which destroys nutrients and produces harmful byproducts. Then, chemicals like hexane, a petroleum-based solvent, are added to pull out even more oil. It smells so bad that in order to make the final product palatable, the oil is deodorized and bleached to remove bad smells and impurities. What’s left is a highly processed product filled with unhealthy compounds.

Seed oils are loaded with omega-6 fatty acids. While small amounts of omega-6 are fine, too much can cause chronic inflammation in your body. This is linked to:

• Heart disease

• Diabetes

• Obesity

• Cancer

• Joint pain

• Autoimmune Disorders

The modern diet is already packed with omega-6 fats, and seed oils make it even worse.

Seed oils are also unstable and break down easily when exposed to heat, light, or air. Cooking with them, especially frying, creates harmful free radicals that damage cells. Over time, this damage contributes to serious health issues like cancer, aging, and brain diseases such as Alzheimer’s.

Sesame seed oil, while often considered a healthier option, has similar risks. Traditionally, it was used sparingly as a flavor enhancer, not as a primary cooking fat. Today, it’s often used in high-heat cooking, which exposes it to the same damaging effects as other seed oils. Like them, sesame oil is high in omega-6 fats, contributing to inflammation when consumed in large amounts.

Regular consumption of seed oils can lead to increased inflammation, which increases chronic diseases such as heart issues and arthritis. The free radicals created during cooking can damage your cells, while the inflammation they cause may slow your metabolism, making it harder to lose weight. The oxidative stress they generate also contributes to memory problems and cognitive decline.

Thankfully, there are healthier alternatives to seed oils that are better for your body. Natural fats like extra virgin olive oil, avocado oil, butter, ghee, coconut oil, and traditional animal fats like tallow and lard are more stable and nutrient-rich. These are the only oils that I allow in my pantry! These options are safer for cooking and don’t carry the same risks of inflammation and cell damage.

To avoid seed oils, cook at home whenever possible and use healthier oils for your meals. Read ingredient labels carefully to avoid hidden seed oils in packaged foods. Choosing whole, unprocessed foods can also help you reduce your exposure to these harmful oils. If you’re unsure how to spot seed oils in your pantry or on food labels, you can learn more through my food label course.

Seed oils have always been risky, but their heavy use in modern diets has made the problem much worse. The good news is that by switching to natural fats, you can lower inflammation, protect your brain and heart, and improve your overall health.

Small changes like these can have a big impact on your well-being.

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In Health,

Dr Jennette Malsbuty