Every cooking oil, and which one for which job

Most oil advice online is written by people selling one particular oil. This is not that. I cook a lot of Indian food at home, I keep a few oils rather than one, and I have opinions about which belongs where. The short version is that there is no single best oil. There is a best oil for the job in front of you, and matching the two is most of what matters.

The one number that decides almost everything is the smoke point. That is the temperature at which an oil stops shimmering and starts to smoke, break down, and turn acrid. Cook past it and you get a bitter taste and a kitchen full of smoke. So the real question for any oil is not "is it healthy" in the abstract. It is "what heat can it take, and what am I cooking."

The quick version

If you want the whole post in one glance, here it is. The prose below explains the why behind each.

Oil	Smoke point	Best for
Extra virgin olive	~190°C (low)	Salads, drizzling, gentle sauté, pasta
Mustard	~250°C (high)	Indian tadka, deep frying
Groundnut, refined	~230°C (high)	Deep frying, stir frying
Coconut, virgin	~175°C (low-med)	Medium heat, dishes wanting coconut flavour
Coconut, refined	~200°C+ (high)	Neutral everyday cooking, frying
Avocado, refined	~270°C (highest)	Searing, deep frying, roasting
Sesame, refined (light)	~210°C (high)	Stir frying, dosa, sautéing
Sesame, toasted (dark)	~175°C (low)	Finishing only, off the heat
Vegetable oil (blend)	~200°C+ (high)	Cheap everyday frying

One thing the table cannot show: for coconut, avocado and sesame, the bottle you buy matters more than the name on it. That is the thread running through this whole piece.

Refined versus cold-pressed, the split that runs through everything

Before the individual oils, one idea that explains half of what follows. Almost every oil here comes in two forms. Cold-pressed, or virgin, or unrefined, keeps more of the flavour, colour and nutrients of the original plant, but has a lower smoke point and a shorter shelf life. Refined has been processed to strip those out, which costs you flavour and some nutrition but buys you a higher smoke point and more stability.

Neither is simply better. A cold-pressed oil is what you want when the flavour is the point and the heat is gentle. A refined oil is what you want when you need it to take real heat and get out of the way. Keep that split in mind and the rest of this makes sense.

Olive oil, the one I love and the one people misuse

Extra virgin olive oil is the best thing you can put on food cold, and the wrong thing to deep fry in. Its smoke point sits around 190°C, which is low by cooking standards, so the fierce heat of an Indian tadka will have it smoking before your cumin has even bloomed. That is not a danger, it is a mismatch. Use the wrong tool and you get a bitter taste, not a health scare.

Where it belongs is anywhere without high heat. Salad dressings, a raw drizzle to finish a dish, bread dipping, a gentle sauté. There you taste everything that makes it worth the money. One honest surprise from looking into it, though. Good extra virgin olive oil is more heat stable than its low smoke point suggests, because its polyphenols slow the breakdown, so a moderate sauté treats it far better than its reputation implies. Love it freely. Just keep it away from the deep fryer.

Mustard oil, the quiet champion for Indian cooking

This was the pleasant surprise when I actually looked at the numbers. Mustard oil has a smoke point around 250°C, which is genuinely high, higher than almost anything else in a normal kitchen. That makes it excellent for exactly the cooking that olive oil fails at, the fierce tadka, the deep fry, the pungent Bengali and North Indian dishes built around its sharp flavour.

If you cook Indian food regularly and you keep only one high heat oil, this is a strong case for it being mustard oil. It handles the temperature, and the flavour belongs in the food rather than fighting it.

Groundnut oil, the high heat workhorse with an allergen footnote

Groundnut oil and peanut oil are the same thing, and it is one of the most useful high heat oils in an Indian kitchen. Refined groundnut oil has a high smoke point, around 230°C, which puts it comfortably in deep-fry and stir-fry territory, alongside mustard and refined avocado. It has a clean, mild flavour that stays out of the way, it resists turning rancid even over long stretches of high heat, and it is a classic across Indian, Chinese and Southeast Asian cooking for exactly those reasons. If you fry a lot, it earns its place on the shelf.

As with everything else here, the refined and unrefined versions are different tools. The refined kind is the neutral high heat workhorse. Unrefined or roasted groundnut oil has a much lower smoke point, around 160 to 175°C, and a pronounced nutty flavour, so it belongs in dressings and finishing rather than the fryer.

One important note, because this site is written for people with allergies. Groundnut oil is peanut oil, and if you are cooking for anyone with a peanut allergy this needs care. The nuance is that highly refined peanut oil has had the peanut proteins removed, and studies have found it generally does not provoke a reaction in peanut-allergic people, which is why restaurants use it freely. Unrefined, cold-pressed or roasted peanut oil is the opposite, since it keeps those proteins and genuinely can trigger a reaction. My honest advice is to never make that call on someone else's behalf. If you are feeding a peanut-allergic guest, the safe move is to avoid groundnut oil altogether rather than to gamble on how refined a given bottle really is.

Coconut oil, where the bottle decides everything

Most articles give coconut oil a single smoke point, and that is the mistake. There are two oils sold under the name and they behave differently. Virgin, unrefined coconut oil smokes low, around 175°C, and carries a real coconut flavour, so it is a medium heat oil for dishes that want that taste, some South Indian cooking, certain sweets. Refined coconut oil is the other animal, smoking higher at 200°C or more with almost no coconut flavour, which makes it a heat tolerant, neutral everyday oil.

So the question is never "is coconut oil good for high heat." It is "which coconut oil is in your hand." Read the label, and do not take the virgin kind to a hot pan expecting it to behave like the refined one.

Avocado oil, the high heat champion at a price

Refined avocado oil has the highest smoke point of any common cooking oil, around 270°C, with a mild, neutral flavour that stays out of the way. On paper it is the most versatile high heat oil you can buy. It sears, it deep fries, it roasts, and it never announces itself in the dish.

Two catches. The first is the same refined versus virgin split as everything else here, since virgin avocado oil is grassier and far lower on the smoke point, closer to olive oil in behaviour. The second is cost. The refined kind is expensive enough that most people keep it for the jobs that genuinely need that ceiling, a proper sear or a fry, rather than pouring it into everything a cheaper neutral oil would handle just as well.

Sesame oil is two different oils wearing one name

This is the one that trips people up, and it is why sesame oil feels so versatile and so confusing at once. There is no single sesame oil. There are two, and they do opposite jobs.

The pale, refined kind, sometimes labelled light sesame oil, is pressed from raw seeds and refined. It has a fairly high smoke point, around 210°C, and a mild flavour. This is a genuine cooking oil. You can stir fry in it, sauté in it, even shallow fry, and it behaves like a sturdy neutral oil with a faint nutty note. It is also the traditional choice for dosa, where the griddle runs hot.

The dark, toasted kind is a completely different tool. Made from roasted seeds, it is intensely aromatic, and its smoke point is much lower, around 175°C. Take it to a hot pan and it smokes fast and turns bitter. This one is a finishing oil. You drizzle it over noodles, dumplings or a stir fry at the very end, off the heat, for its flavour. You do not cook in it.

So when someone tells you sesame oil is great for high heat and someone else tells you it burns instantly, they are both right. They are talking about different bottles. Check which one you have before you decide what to do with it.

Vegetable oil, the anonymous workhorse

Generic vegetable oil is usually a blend, often soybean, canola, or a mix of refined oils. Its smoke point is high enough for frying, typically north of 200°C, its flavour is neutral, and it is cheap. For everyday shallow frying and general cooking where you want the oil to disappear, it does the job without fuss.

The only real caveat is transparency. The label rarely tells you exactly what is in the blend, and that blend can include palm oil. If you are avoiding a particular oil, generic vegetable oil is the one place it can hide without being named. If that matters to you, buy a single named oil instead, so you know exactly what you are cooking with.

Margarine and vegan butter, and a warning worth reading

Margarine has a bad reputation that it mostly no longer deserves, and this genuinely surprised me when I looked into it. The old danger was trans fats, the artificially hardened fats that raise bad cholesterol and lower the good kind. Modern margarines have removed them. Today's soft margarines are typically high in unsaturated fat and often carry only half the saturated fat of butter, which on the numbers makes a soft tub margarine a reasonable choice rather than a villain.

Two things are worth knowing. Soft tub margarine is a better pick than hard stick margarine, which packs in more saturated fat to stay solid. And here is the warning that matters most for anyone cooking plant based: to make vegan butter blocks firm at room temperature, manufacturers usually add a saturated fat, and that fat is very often coconut or palm oil. So the vegan butter in your fridge may contain the exact palm oil you thought you were avoiding. Read the ingredients. It is the one place palm oil sneaks back into a plant based kitchen.

Which oil for which dish

All the smoke point theory earns its keep here, in the one question that actually matters at the stove: what do you pour in the pan for the thing you are cooking. Here is how it shakes out across a real week of cooking.

Dosa. Refined sesame oil, or the traditional South Indian gingelly oil, is the classic choice, and a good one. The griddle runs hot, so it has to be the pale refined kind, not the dark toasted bottle, which would smoke and turn bitter. A cook who reaches for toasted sesame here has grabbed the wrong bottle. Refined, and you get a faint nutty edge that belongs in the dish.

Idli. A quiet trick answer. Idli is steamed, so no oil ever gets hot and the smoke point is irrelevant. The only oil involved is the thin smear in the mould that stops the batter sticking, and for that any neutral food oil works, though a little sesame or coconut oil is traditional. Do not overthink it.

Tadka and deep frying. This is where high heat rules and the low smoke point oils drop out. Mustard oil is the standout for Indian cooking, high enough to take the heat and with a flavour that belongs in the food. Refined avocado oil is the premium neutral alternative when you do not want any added flavour. Groundnut oil is another excellent choice here, high smoke point, neutral flavour, and it holds up over long frying. Refined coconut or plain vegetable oil both do the job for everyday frying too.

Aglio e olio, and pasta in general. Always olive oil, and this is olive oil used exactly right. You are warming garlic and chilli gently in the oil rather than searing anything, so you stay well under its smoke point, and the oil is not just the cooking medium, it is the sauce. Extra virgin, low heat, no compromise. This is the dish that proves olive oil is not fragile, it is just for gentle heat.

Salads and anything raw. Extra virgin olive oil, every time, or a virgin nut oil if you want something different. No heat means you get the full flavour you paid for.

Finishing a stir fry or noodles. A few drops of toasted sesame oil off the heat, added at the very end. This is the one job the dark aromatic bottle is made for, and the one job the refined bottle cannot do as well.

Everyday neutral cooking. Refined coconut, refined avocado, or plain vegetable oil. Heat tolerant, flavourless, and they get out of the way.

Storing oil, and knowing when it has turned

Oil does not last forever, and rancid oil is worth avoiding, both because it tastes stale and metallic and because it is simply past its best. The rule follows the same logic as everything else here. The more unsaturated an oil, the faster it goes off. So the delicate ones, toasted sesame, flaxseed, walnut and other nut oils, want a cool dark cupboard, and some are happiest in the fridge. The more saturated ones, coconut especially, are stable at room temperature for a long time.

Two habits help. Keep oils away from light and heat, so not on the shelf right beside the stove, however convenient that is. And trust your nose. If an oil smells sharp, waxy, or like old crayons rather than clean and characteristic, it has turned, and no amount of cooking will bring it back. Bin it.

Reusing frying oil

If you deep fry, you will wonder whether you can use the oil again, and the honest answer is yes, but carefully, and not forever. Let it cool, strain it through a fine sieve or muslin to get the burnt bits out, and store it somewhere cool and dark. If it still smells clean, it is good for one or two more fries. The moment it turns dark, smells sharp, or starts to smoke at a lower temperature than it used to, it is done. Reheating the same oil over and over is one of the clearest ways to build up the harmful compounds worth avoiding, so this is the one place I would not push your luck.

A word on the seed oil panic

You have probably seen the noise online that industrial seed oils, the sunflowers and canolas and soybeans of the world, are uniquely inflammatory and quietly harming everyone. It is worth addressing plainly, because the fear is loud and the evidence is not.

The measured position is that the strong claims are not well supported. Seed oils are high in omega-6 fats, and the concern is about getting the balance of omega-6 to omega-3 badly out of proportion, which is really a question of overall diet rather than one villainous ingredient. A kitchen that cooks mostly whole food and uses a range of oils is not the problem the internet says it is. I would not lose sleep over a refined seed oil used sensibly. I would spend that worry on trans fats instead, which are genuinely worth avoiding, and which the next section covers.

Oils to avoid, and why

Not every oil belongs in a kitchen, and the reasons differ, so it is worth separating the truly-never from the merely-misused.

Never cook with these. Castor oil is a laxative and an industrial lubricant, not a food oil, and it has no place in cooking at all. And any oil pushed past its smoke point and reheated again and again until it is dark and acrid, which is how a lot of deep fried food goes wrong, since repeatedly overheated oil builds up genuinely harmful compounds. That last one is less about the oil you buy and more about how it is treated.

Avoid or minimise, on my own reasoning rather than settled fact. Palm oil, for the environmental and saturated fat reasons below. And anything with hydrogenated or partially hydrogenated oil on the label, which signals trans fats. If there is one fat that earns the phrase "avoid at all costs," it is this one, because trans fats raise your bad cholesterol and lower the good kind at the same time, a rare double harm. If you read one thing on an ingredient list, read for that word.

The rest of the oils in this post are not good or bad in the abstract. They are right or wrong for the job in front of you. Match the oil to the heat and the dish, and most of the anxiety around cooking fats simply falls away.

A word on palm oil, which I avoid

I do not cook with palm oil, and I am not neutral about it. Two reasons, and I want to be honest about how strong each one actually is.

The first is environmental, and it is the one I hold without reservation. Palm oil cultivation is among the largest drivers of tropical deforestation and habitat destruction. That is not seriously disputed, and for me it is reason enough on its own.

The second is health, and here I will be straight that the evidence is softer than the internet pretends. Palm oil is very high in saturated fat, and mainstream nutritional guidance is to limit saturated fat and replace it with unsaturated fats, which is linked to better cholesterol and lower cardiovascular risk. That is a real reason to be cautious. What I will not claim is that palm oil specifically has been proven to wreck your heart, because the direct evidence is genuinely mixed, and some recent work suggests processed fats like it may be less harmful in everyday amounts than once thought. So treat my health objection as a conviction built on the saturated fat case, not as settled science.

Put the two together, a solid environmental objection and a reasonable health caution, and for me it lands clearly on the side of leaving it out. You might weigh the health part more lightly than I do. That is fair. But I wanted the real reasoning on the table rather than hiding behind the word "unhealthy," and the environmental case stands regardless of where you land on the rest.