Seed oils here, seed oils there. These days, you can hardly pay attention to any nutrition talk without hearing about them.
The research is mixed, though.
Nutrition scientists at Johns Hopkins will tell you that seed oils are associated with lower risk of cardiovascular disease, heart attack, and diabetes.
Healthline researchers note that when heated, seed oils high in polyunsaturated fats produce more oxidation byproducts than more stable oils, such as olive oil, and that the refining process strips out antioxidants that would otherwise protect the oil.
And interestingly, both sets of researchers are citing real studies.
I'm not going to tell you seed oils are poison.
But I generally try to reduce them at home, mainly because they're already in so much of what I eat when I don't cook my own food. So controlling what I cook with is one of the few levers I actually have.
Seed oils are vegetable oils extracted from seeds, usually using high heat and chemical solvents to get the oil out at scale. The ones that show up most in home cooking: canola oil, vegetable oil, sunflower oil, safflower oil, corn oil, soybean oil, and grapeseed oil. Cottonseed oil too, though you're more likely to encounter that one in packaged foods than in your actual kitchen.
The issue isn't that any single meal cooked in canola oil is going to hurt you.
The issue is that these oils are in so much of what we eat already (packaged snacks, restaurant food, condiments, sauces) that adding more at home just keeps the exposure high.
For most everyday cooking, extra virgin olive oil does the job. Sautéing vegetables, cooking eggs, finishing pasta, drizzling on things.
Buy a decent bottle (not the cheapest one on the shelf, because really cheap olive oil can sometimes be diluted with lower-quality oils), and use it.
For higher-heat cooking like stir-fries or searing meat, many people use avocado oil. It has a neutral flavor, so it doesn't compete with whatever you're cooking. It's more expensive than olive oil, but you don't need to use a lot of it.
Coconut oil is another option, especially for baking or anything where you want a slightly richer flavor. It's solid at room temperature, melts easily, and is stable at higher temps. The flavor is mild in refined versions, more distinct in unrefined.
Butter and ghee are also solid options for cooking if you eat dairy. Ghee in particular handles high heat well and keeps for a long time unrefrigerated.
Go to your kitchen and look at what oil you have. If it's vegetable oil or canola oil, you can either replace it immediately or just not buy it again when it runs out.
Get a bottle of olive oil and an avocado oil spray or a bottle of avocado oil for the high-heat stuff. That's the whole transition.
You don't need to throw anything away mid-bottle if budget is tight. Just phase it out.
Packaged foods with seed oils are a separate category. If you're trying to eliminate seed oils from your diet entirely, reading labels becomes necessary because they're in salad dressings, chips, crackers, mayonnaise, hummus, granola bars, and most fried restaurant food. That's a bigger project.
For now, getting your own cooking oil sorted is a realistic first step. The kitchen swap takes about a grocery trip and maybe a little extra money upfront. The packaged food part takes longer and can be done one step at a time.
Start with your cooking oil.