Seed Oils: Why People Are Avoiding Them and What to Use Instead

What Are Seed Oils?

Seed oils are cooking oils extracted from the seeds of plants using industrial processing methods. The most common seed oils are soybean oil, canola (rapeseed) oil, corn oil, sunflower oil, safflower oil, cottonseed oil, and grapeseed oil. These oils dominate the modern food supply — they're found in nearly every processed food, restaurant fryer, and household kitchen.

Seed oils are sometimes called "vegetable oils," though this is misleading since they come from seeds, not vegetables. They require heavy industrial processing to extract, including chemical solvents (typically hexane), high heat, bleaching, and deodorising. The final product bears little resemblance to the original seed.

Why Are People Avoiding Seed Oils?

The anti-seed-oil movement has grown significantly since 2020, driven by health-conscious consumers questioning the modern diet. Here are the main concerns:

High omega-6 content: Seed oils are extremely high in omega-6 linoleic acid. While some omega-6 is essential, the modern Western diet provides omega-6 to omega-3 ratios of 20:1 or higher — far from the estimated ancestral ratio of 1:1 to 4:1. Excess omega-6 is linked to increased inflammation, which underlies many chronic diseases.

Oxidation during processing and cooking: The polyunsaturated fats in seed oils are chemically unstable. They oxidise easily when exposed to heat, light, and air — all of which occur during both manufacturing and cooking. Oxidised fats generate aldehydes, lipid peroxides, and other compounds associated with cellular damage.

Industrial processing: The extraction process for seed oils involves chemical solvents, high temperatures, and multiple refining steps that strip away any natural nutrients while potentially introducing processing residues. Compare this to pressing an olive for oil or rendering beef fat for tallow — processes that have been used for thousands of years.

Historical novelty: Seed oils entered the human diet only in the early 1900s with the invention of industrial seed crushing technology. Human consumption of linoleic acid has increased by approximately 300% since 1960. Some researchers argue our bodies haven't evolved to process these fats in such quantities.

What Does the Research Say?

The science on seed oils is actively debated. Some studies suggest that replacing saturated fat with polyunsaturated seed oils reduces cardiovascular risk markers. However, other research paints a more nuanced picture.

A re-analysis of the Minnesota Coronary Experiment (published in BMJ, 2016) found that while replacing saturated fat with vegetable oil did lower cholesterol, it actually increased mortality — the opposite of what was expected. The Sydney Diet Heart Study found similar results.

Research on heated seed oils consistently shows cause for concern. When polyunsaturated oils are heated to frying temperatures, they produce significantly more toxic aldehyde compounds than saturated fats like beef tallow or coconut oil.

What Should You Use Instead of Seed Oils?

Beef tallow: The best all-purpose replacement. High smoke point, excellent stability, rich flavour, and nutritional benefits. Our Organic Grass-Fed Beef Tallow is pure, single-ingredient cooking fat from grass-fed Kuwaiti cattle.

Ghee or butter: Excellent for sautéing and baking. Ghee has a higher smoke point than butter and adds a rich, nutty flavour.

Extra virgin olive oil: Best for low-to-medium heat cooking, salad dressings, and finishing. Choose cold-pressed from reputable sources.

Coconut oil: Good for baking and medium-heat cooking. Its high saturated fat content makes it stable, though the flavour doesn't suit every dish.

How to Avoid Seed Oils in Your Diet

The biggest challenge is that seed oils are hidden everywhere. Read ingredient labels carefully — soybean oil, canola oil, and sunflower oil appear in bread, crackers, salad dressings, sauces, snack foods, and virtually all fried restaurant food.

Start by replacing your home cooking oils with tallow, ghee, butter, and olive oil. Then gradually reduce processed foods that contain seed oils. When eating out, ask what oil the restaurant uses for frying — most use cheap seed oils, which is why home-cooked food using quality fats often tastes and feels better.

Frequently Asked Questions

Are all seed oils bad?

The concern is primarily with highly processed, high-omega-6 seed oils used in large quantities for cooking. Cold-pressed seed oils used in small amounts as finishing oils (like sesame oil in Asian cuisine) are less concerning because they're less processed and used in smaller quantities.

Is canola oil a seed oil?

Yes. Canola oil is extracted from rapeseed and undergoes the same industrial processing as other seed oils, including solvent extraction, refining, bleaching, and deodorising. Despite marketing claims about its heart health benefits, it shares the same processing concerns as other seed oils.

What do restaurants use for frying?

Most restaurants use soybean oil, canola oil, or blended vegetable oils for frying due to their low cost. Some premium restaurants use beef tallow, duck fat, or peanut oil. If you're concerned about seed oil exposure, cooking at home with quality fats like grass-fed tallow gives you full control over what you eat.