If you spend any time reading about nutrition online, you have probably seen the seed oil debate.
Some people claim seed oils are one of the biggest problems in the modern diet. Others say there is nothing wrong with them at all.
Most of this discussion ends up producing more noise than clarity.
To understand the issue properly, we need to step back and ask a more useful question.
What is actually happening inside the body when we talk about inflammation, and how do the fats we cook with influence it?
What Inflammation Actually Is
Inflammation is not automatically a bad thing.
It is a natural biological response used by the immune system to repair damaged tissue and defend the body against infection.
Short term inflammation is part of normal healing. If you have ever twisted an ankle, had a sore joint after exercise, or noticed swelling after a cut, that is inflammation doing its job.
Problems arise when inflammation becomes chronic and low level, meaning the body stays in a constant state of mild immune activation.
Many people recognise the feeling without realising what is behind it.
You feel a bit sluggish.
Your joints feel stiff.
You feel tired even when you have slept enough.
Chronic inflammation has been linked to conditions such as cardiovascular disease, metabolic syndrome and type 2 diabetes. Diet is only one factor among many, but the types of fats people consume regularly can influence inflammatory pathways.
Why Industrial Seed Oils Became So Common
To understand why seed oils are now everywhere, you have to look at the food manufacturing system rather than just the chemistry.
Seed oils such as soybean, sunflower, corn and canola oil are widely used because they are:
• inexpensive to produce at scale
• easy to refine into a neutral product
• highly stable for long shelf life
• versatile in processed food manufacturing
These properties make them extremely attractive for producing packaged foods.
They appear in:
• snack foods
• baked goods
• salad dressings
• ready meals
• restaurant frying oils
• protein bars and health snacks
One consequence of this system is that it allows manufacturers to take very low cost agricultural raw materials and transform them into highly processed food products.
The oil itself is not the entire problem. The broader system of ultra processed foods built around these ingredients is where many nutrition researchers focus their attention.
Why Processing Matters More Than the Label
Much of the public debate focuses on whether seed oils themselves are harmful.
A more useful discussion focuses on how oils are processed.
Many industrial oils are extracted using solvent methods, then refined through several steps including degumming, bleaching and deodorisation. These processes are designed to create a neutral, shelf stable oil suitable for large scale food production.
Refining itself is not automatically unsafe. However, it produces oils that are far removed from their original raw ingredients.
The same principle can apply to other oils as well.
Even olive oil, widely recognised as a healthy option in its extra virgin form, can be heavily refined or blended when sold as generic “olive oil”. In these cases the oil may have undergone significant processing to remove flavour defects or stabilise shelf life.
In other words, the processing method often matters more than the type of oil.
Fat Structure and Inflammation
Another factor is the fatty acid composition of different oils.
Seed oils tend to contain higher levels of polyunsaturated omega 6 fatty acids, particularly linoleic acid.
Research by Simopoulos published in Biomedicine and Pharmacotherapy highlighted how modern diets often contain a much higher omega 6 to omega 3 ratio than historical dietary patterns.
This imbalance has been discussed as a potential contributor to inflammatory signalling in certain contexts.
By comparison, oils dominated by monounsaturated fats behave differently in the body.
Monounsaturated fats such as oleic acid have been associated with favourable cardiovascular outcomes and are less chemically reactive during cooking compared with highly polyunsaturated oils.
This difference in fatty acid structure is one reason oils such as olive oil, avocado oil and macadamia oil are often highlighted in nutrition research.
Why Nut Oils Deserve More Attention
One aspect of the conversation that is often overlooked is the difference between seed oils and nut oils.
Nuts naturally contain oils with higher proportions of monounsaturated fats and lower levels of polyunsaturated fats compared with many common seed oils.
Macadamia oil is one of the most monounsaturated oils available, often containing around 75 to 80 percent monounsaturated fat.
This composition provides several advantages for everyday cooking:
• strong oxidative stability
• lower reliance on heavy industrial refining
• favourable fatty acid balance
When cold pressed and unrefined, macadamia oil also avoids the solvent extraction and intensive refining steps used for many industrial oils.
Moving Past the Noise
The seed oil debate often turns into a simple argument between two extremes.
One side claims seed oils are dangerous. The other insists they are completely harmless.
The more useful perspective sits somewhere in the middle.
Industrial food systems rely heavily on refined oils because they are cheap and scalable. Highly processed foods built around those ingredients are increasingly linked with poor health outcomes.
At the same time, not all oils are the same.
Processing methods, fatty acid structure and overall dietary patterns all matter.
Understanding these differences allows people to make more informed choices without falling into online nutrition arguments.
The Practical Takeaway
Inflammation is influenced by many factors, including diet, lifestyle and overall metabolic health.
Cooking oils are only one part of the picture, but they are used frequently enough to make thoughtful choices worthwhile.
Choosing oils that are:
• minimally processed
• structurally stable
• naturally rich in monounsaturated fats
is a practical step many people take to reduce reliance on heavily industrialised ingredients.
Nut oils, particularly macadamia oil, fit naturally into that approach because their chemistry and processing align more closely with whole food ingredients than large scale industrial oil production.
Sometimes the best way to cut through the debate is simply to understand what is actually in the oil you cook with every day.