Stop Panicking About “Seed Oils”! 12 Q&As Debunk the Health Myths with Science

❓Are seed oils harmful?

It’s a misconception to claim that all seed oils are harmful.

Seed oils refer to oils extracted from the seeds of plants — such as soybean oil, corn oil, sunflower oil, and grape seed oil.

These seeds are commonly used for oil extraction because they are naturally rich in fat, yield large quantities of oil, and are easy to store.

The oils themselves are not inherently “toxic” or “unhealthy.” What really matters is how they are processed, and how you use them in your kitchen.

If oils are highly refined, used at very high temperatures, or repeatedly reheated (like in deep frying), they may produce oxidation compounds that are detrimental to health — and this applies to all oils, not just seed oils.

However, when cold-pressed and unrefined oils are used in moderate amounts and under low to medium heat, they are perfectly safe to consume.

What’s more, many oils recommended by nutritionists — like walnut oil, flaxseed oil, and perilla oil — are also technically seed oils.

If we reject every oil just because it comes from a seed, we’d have to throw out many highly nutritious options as well.

The real focus shouldn’t be on whether an oil comes from a seed, but on how it’s processed, how it’s used, and how it fits into your overall diet.

❓What is "industrial seed oil"?

"Industrial seed oil" is not a scientific term — it's a popular phrase that typically refers to seed oils produced through large-scale industrial processing and refining.

These oils are usually extracted using high-heat pressing or solvent extraction (such as with hexane), followed by processes like degumming, bleaching, and deodorizing. The final product is clear, neutral in flavor, and has a long shelf life.

Common refined oils on the market — such as soybean oil, corn oil, and sunflower oil — all fall into this category.

In fact, even the widely recognized olive oil has a refined version. "Light olive oil" is processed to remove color, flavor, and impurities — not to make it "healthier," but to make it more stable and neutral.

And it's not just plant oils — animal fats like lard, tallow, and fish oil are also often refined to remove odors, improve clarity, and enhance shelf stability.

In reality, most of the oils we consume daily — plant or animal — are technically industrially processed.

The key issue isn’t whether an oil is "industrial" — it's whether the processing degrades its nutritional value, introduces risks, or matches your actual cooking style and intake.

When evaluating an oil's health value, we need more than fear of buzzwords. Look at its ingredients, production method, intended use, and your overall diet.

❓Do polyunsaturated fats (PUFAs) oxidize easily when heated?

Yes — PUFAs are more prone to oxidation at high temperatures, but that doesn’t mean they’re unsafe in everyday cooking.

PUFAs (polyunsaturated fatty acids) contain multiple double bonds, which makes them less stable than monounsaturated or saturated fats.

Under prolonged high heat — especially in deep-frying or reused oils — PUFAs are more likely to oxidize and form harmful compounds.

However, in typical home cooking scenarios like stir-frying at medium heat or single-use heating, PUFA-rich oils can still be used safely.

In fact, many oils rich in PUFA — like flaxseed oil or perilla oil — are important sources of Omega-3 and are best used in cold dishes or low-heat cooking.

So when we talk about oxidation, the cooking method matters more than the oil type alone.

❓Do manufacturers "usually" add BHT to vegetable oils?

No. The use of BHT in vegetable oils is actually limited and far less common than claimed.

While BHT (butylated hydroxytoluene) is a permitted antioxidant in food production, its use is strictly regulated and more commonly found in fat-sensitive products like nuts or dried meats.

In modern oil production — especially in countries like New Zealand, Australia, and China — most vegetable oils rely on natural antioxidants, such as vitamin E (tocopherols), rather than synthetic ones like BHT.

Furthermore, cold-pressed or unrefined oils — such as extra virgin olive oil or flaxseed oil — almost never contain any additives at all.

So the claim that “vegetable oils usually contain BHT” is an exaggeration — and in most cases, simply false.

❓Is BHT an endocrine disruptor?

There is currently no conclusive human evidence that dietary levels of BHT disrupt the endocrine system.

BHT (butylated hydroxytoluene) has shown weak estrogen-like activity in some animal studies — but only at extremely high doses far beyond normal consumption.

For example, in rat studies, hormonal changes were observed only at doses over 200 mg/kg/day. For a 60 kg adult, this would mean ingesting 12 grams of BHT — the equivalent of eating around 60 kilograms of oil in a day.

Major health authorities including the WHO, EFSA, and FDA continue to classify BHT as safe when used within regulated limits.

Calling BHT a definitive endocrine disruptor is misleading, unscientific, and unnecessarily fear-inducing.

❓How much BHT would it take to cause hormonal changes?

Hormonal effects from BHT have only been observed in animal studies at extremely high doses — far beyond what any human would consume through diet.

In rat studies, estrogen-like responses (like increased uterine weight) appeared only at doses above 200 mg per kilogram of body weight per day.

For a 60 kg human, that would be equivalent to ingesting 12 grams of BHT daily — which means consuming about 60 kilograms of vegetable oil containing 200 mg/kg of BHT, every single day.

In reality, most edible oils don’t even contain BHT, and if they do, the levels are well below 200 mg/kg — usually within strict legal limits.

So the levels of BHT one might consume from food are nowhere near enough to trigger hormonal effects.

❓Is Omega-6 always bad? Should we minimize it?

No. Omega-6 is an essential fatty acid — your body needs it to function properly.

It plays a critical role in building cell membranes, regulating inflammation, and supporting immune responses. So eliminating it entirely is neither possible nor advisable.

The real issue isn’t how much Omega-6 you eat — it’s that most people consume too little Omega-3, throwing the ratio out of balance.

Today’s typical Western diet has an Omega-6 to Omega-3 ratio of 15:1 or even higher, while the ideal ratio is believed to be closer to 4:1 or less.

Omega-6–rich oils can be part of a healthy diet, especially when not paired with deep frying, trans fats, or ultra-processed foods.

Nutrition is about balance, not elimination.

❓Is canola oil really high in Omega-6?

Many people mistakenly believe canola oil is high in Omega-6, but the truth is — it has one of the most balanced fatty acid profiles among all cooking oils.

Modern canola oil comes from low-erucic acid rapeseed and is known for its nutritional advantages.

Here’s the approximate fatty acid breakdown:

• Monounsaturated fats (Omega-9): ~60%
• Omega-6: ~18–20%
• Omega-3 (ALA): ~9–11%

This means its Omega-6 to Omega-3 ratio is around 2:1 — far better than soybean oil (8:1), corn oil (20:1), or sunflower oil (>100:1).

Canola oil is widely accepted in the nutrition world as a healthy and affordable everyday oil.

If you're concerned about excessive Omega-6, it’s oils with nearly zero Omega-3 — like corn, sunflower, and safflower oil — that deserve more scrutiny.

❓Are peanut oil and rice bran oil high in Omega-6?

Not really. Although both come from “seeds,” their fatty acid profiles are quite different from oils like sunflower or corn oil.

Let’s look at the numbers:

• Peanut oil: ~30–32% Omega-6, over 45% Omega-9
• Rice bran oil: ~33–36% Omega-6, with added benefits from phytosterols and gamma-oryzanol

That’s significantly lower than corn oil (~55%), sunflower oil (~65–70%), or safflower oil (>75%).

Peanut and rice bran oils have a mild flavor and work well for stir-frying. Used in moderation, they won’t throw your fat balance off track.

Focus on your total dietary pattern and Omega-3 intake — not vilifying any single oil.

❓Are blended “vegetable oils” always unhealthy?

Not necessarily. The term “vegetable oil” is often misunderstood. It simply refers to a blend of oils from different plant sources.

Many commercial “blended oils” include combinations like soybean + canola + rice bran + peanut oil to balance flavor, stability, or nutrition.

The key question is not whether it’s blended, but: (1) Are the ingredients disclosed? (2) Does it include trans fats or hydrogenated oils? (3) Is it dominated by high-Omega-6 oils without any Omega-3?

Some premium brands clearly label blends like “cold-pressed canola + rice bran + olive oil,” which may actually offer better fatty acid profiles and antioxidant content.

So don’t judge a bottle just because it says ‘vegetable oil.’ Learn to read the ingredients and fat breakdown first.

❓Are walnut oil and almond oil considered seed oils?

Yes — broadly speaking, they are.

From a botanical perspective, walnuts, almonds, sesame, flaxseed, and perilla are all technically seeds of plants.

So the oils extracted from them fall under the category of “seed oils.”

However, we rarely see walnut or flaxseed oil being demonized as “industrial seed oils” — because they are usually cold-pressed and minimally processed.

So if we blanket-label all “seed oils” as unhealthy, we unfairly include some of the most nutrient-rich oils in that category.

The real threats are over-processing, deep frying, and long-term imbalance — not the seed itself.

❓Should I completely avoid Omega-6?

No — Omega-6 is an essential fatty acid. Your body needs it for many vital functions.

It plays important roles in cell structure, immune function, and hormone synthesis. The problem isn’t Omega-6 itself, but the imbalance with Omega-3.

Modern diets tend to be extremely low in Omega-3, which makes Omega-6 intake seem “excessive” by comparison.

The solution isn’t to cut out Omega-6, but to restore balance by improving your diet and taking high-purity Omega-3 fish oil (≥90% EPA+DHA) to optimize the ratio.

High-quality Omega-3 fish oil helps reduce inflammation, improve blood lipids, and balance out excess Omega-6 in the body.

Nutrition is not about elimination — it's about improving the ratios.