27 juin 2025

The 7 vegetable oils to always have for healthy cooking

The official Swiss nutrition recommendation for adults fits into one line: two tablespoons of vegetable oil a day, roughly 20 grams, of which at least one tablespoon should be rapeseed oil. Not seven oils. Two, one of them named.

That does not make the others useless, but it does reorder the priorities. Rapeseed covers alpha-linolenic acid, olive supplies the phenolic compounds and handles heat, and everything else comes down to flavour, budget and habit. A cupboard holding seven oils is a cook’s pleasure, not a nutritional requirement.

Three widespread beliefs are worth clearing up first, because they drive most of the bad purchases.

Walnut oil is not a source of vitamin E. The French ANSES Ciqual table gives it 1.81 mg per 100 g, which is 0.18 mg per tablespoon, about 1.5 % of the Swiss nutrient reference value. Sunflower oil contains thirty times more.

Smoke point does not decide whether an oil suits frying. The review published in Foods in 2024 states it plainly: smoke point is no longer considered a precise indicator of an oil’s susceptibility to degradation. In frying trials, extra virgin olive oil took 33 hours to reach the legal limit of 25 % total polar compounds, sunflower oil 17 hours, linseed oil close to 4 hours.

Coconut oil is not an everyday cooking oil. A single tablespoon delivers roughly 8.4 g of saturated fat, which is 42 % of the daily 20 g ceiling the NHS recommends for an adult woman and 28 % of the 30 g ceiling for a man.

What actually determines the value of an oil

An edible oil is 95 to 98 % triglycerides. What separates one oil from another is the nature of the fatty acids esterified onto those triglycerides, plus a minority fraction of so-called minor components: tocopherols (vitamin E), sterols, squalene, carotenoids, phenolic compounds and chlorophylls. That fraction is a few per cent by mass, but it decides the oil’s stability, colour, flavour and part of its nutritional interest.

The figures below come from the 2020 ANSES Ciqual table, given per 100 g of oil. One tablespoon is about 10 g, so divide by ten.

Oil	Saturated	Monounsaturated	Polyunsaturated	of which ALA	Vitamin E
Rapeseed	7.3 g	59.7 g	26.9 g	7.54 g	27.7 mg
Extra virgin olive	15.2 g	73.1 g	7.2 g	0.65 g	22.3 mg
Sunflower	11.1 g	27.6 g	56.3 g	0.05 g	57.3 mg
Coconut	84.0 g	8.6 g	1.7 g	traces	12.8 mg
Avocado	17.9 g	65.2 g	10.5 g	0.55 g	45.3 mg
Sesame	14.9 g	40.2 g	40.0 g	0.38 g	1.1 mg
Walnut	10.0 g	16.8 g	69.6 g	11.9 g	1.81 mg

Two columns are enough to sort these oils for everyday use. The saturated fat column isolates coconut oil, which plays in a different category from all the others. The alpha-linolenic acid column isolates rapeseed and walnut, the only two supplying amounts that count within a day.

Notice in passing that sesame and walnut oil sit at the bottom of the vitamin E column. People often assume the opposite, because they conflate the oil with the seed it came from. Sesame seeds are rich in calcium and minerals; the oil pressed from those seeds is not, because the minerals stay in the press cake. That distinction holds for every oil: pressing a seed does not carry its minerals into the liquid.

Smoke point: the most quoted number and the least useful

Smoke point is the temperature at which an oil starts to smoke visibly. What happens at that moment is hydrolysis: triglycerides split into free fatty acids and glycerol, and glycerol loses a water molecule to form acrolein. Acrolein is the main component of that bluish smoke, and it irritates skin and mucous membranes.

The key point is that smoke point depends mainly on free fatty acid content and on chain length, not on the degree of unsaturation. A freshly refined oil has few free fatty acids and smokes late. The same oil, after a few frying sessions, smokes noticeably earlier, because hydrolysis has released fatty acids on contact with the water in the food. An oil’s smoke point is therefore not a fixed physical constant; it shifts while you cook.

What matters for frying is resistance to oxidation, and that depends on unsaturation. The more polyunsaturated fatty acids an oil holds, the faster it degrades into total polar compounds, the measurement on which most countries set their legal discard limit, generally between 24 and 30 %. The trials cited in the 2024 review give the orders of magnitude: 33 hours of frying for extra virgin olive oil, 17 hours for standard sunflower oil, under 4 hours for linseed oil. An oil rich in oleic acid lasts about twice as long as one rich in linoleic acid, and ten times as long as one rich in alpha-linolenic acid.

The practical conclusion contradicts what you usually read: for long, hot cooking, choose an oil rich in monounsaturated fatty acids rather than an oil with a high smoke point. That points to olive oil, high-oleic sunflower oil and groundnut oil. It rules out linseed oil, which has no business in a hot pan, and walnut oil for the same reason.

Frying and hot cooking in practice

The 2024 review puts the optimum frying temperature between 150 and 190 °C. Above that, degradation accelerates without improving the result; below it, the food absorbs more oil because the crust forms too slowly.

Three factors weigh as heavily as the choice of oil. The first is the number of cycles: reheating and cooling the same oil several times degrades it faster than continuous frying of equivalent duration. The second is the ratio of food to oil volume: a small bath crowded with food hydrolyses quickly. The third is filtering, because charred debris and metal traces act as oxidation catalysts.

The end-of-life signs of a domestic frying bath are visible without instruments: marked darkening, rising viscosity, persistent foam on the surface, an acrid smell, and smoke appearing at a temperature where the oil did not smoke on first use. That last sign is the most reliable, precisely because smoke point falls as the oil degrades.

One point people miss about frying: some of the oil ends up in the food, and temperature decides how much. Oil that is too cool forms the crust more slowly, so the food loses moisture for longer and takes up more fat. The usual complaints about fried vegetables often concern a pan set too low rather than the method itself. If calories are the concern, hot oil and short times gain you more than the choice of oil ever will. For vegetables where nutrient retention is the priority, another method applies anyway: our article on gentle steam cooking compares the cooking methods on that basis.

On the fumes themselves, a review published in Foods in 2026 collects the emission factors measured under typical cooking conditions: 17.966 to 71.923 mg of volatile organic compounds per minute per kilo of oil, and 0.458 to 1.820 mg of formaldehyde in the same units. Cooking oil fumes also contain polycyclic aromatic hydrocarbons, benzene compounds and ultrafine particles below 0.1 micrometres. That is not a reason to stop cooking. It is a reason to open the window and switch on the extractor before heating the oil rather than after you see smoke.

Rapeseed oil, the one the recommendation names

The Swiss recommendation names rapeseed for a measurable reason: it is the only cheap, neutral-tasting everyday oil that supplies alpha-linolenic acid in meaningful quantity. One tablespoon provides 0.75 g of ALA. For comparison, EU Regulation 432/2012 on health claims, whose content the Swiss ordinance mirrors, states that the effect of ALA on blood cholesterol is obtained with a daily intake of 2 g.

The overall profile explains the rest: 7.3 g of saturated fat per 100 g, the lowest of the seven, and a linoleic to alpha-linolenic ratio of about 2.6 to 1, which is unusually favourable. Most seed oils sit at 50 to 1 or higher.

A note on erucic acid, which comes up regularly with rapeseed. The Swiss contaminants ordinance sets a maximum of 20 g per kilo of erucic acid in vegetable oils and fats, expressed against total fatty acid content. Rapeseed varieties grown in Europe since the 1970s have been bred to be low in erucic acid, and the Codex data reproduced in the 2024 review give a range of zero to 2 % for commercial rapeseed. For shop-bought oil, the question was settled long ago.

There is a real drawback, though: virgin rapeseed oil oxidises quickly, precisely because of its ALA. Buy small bottles, keep them cool and away from light, and do not fry with it.

Olive oil and the only genuinely specific claim

Olive oil is the only oil on this list with a health claim attached to its own phenolic compounds, and the conditions attached to that claim are instructive. Regulation 432/2012 authorises the wording about protecting blood lipids from oxidative stress on condition that the oil contains at least 5 mg of hydroxytyrosol and its derivatives per 20 g of oil, and that the consumer is told the effect is obtained with 20 g of oil per day.

Two practical consequences follow. First, the claim does not apply to refined olive oil, since refining strips out most of the phenolic compounds. Second, the reference dose is exactly the Swiss recommendation for all oils combined, so if you want that effect, olive already takes up your entire daily ration and there is no room left for the tablespoon of rapeseed.

On fatty acids, extra virgin olive oil sits at 73.1 g of monounsaturates per 100 g, almost all oleic acid. A GRADE-based meta-analysis published in 2026 in Diabetology & Metabolic Syndrome pooled 26 randomised controlled trials and 1,244 participants to assess high-oleic diets. The results are real but small: total cholesterol down 0.14 mmol/L, LDL down 0.13 mmol/L, no effect on HDL, triglycerides, fasting glucose, fasting insulin or HOMA-IR. The authors themselves describe the absolute changes as modest and talk about a complementary role.

That deserves saying bluntly. Replacing saturated fat with olive oil improves the lipid profile a little. It does not transform a diet, and the size of the effect does not justify the prices charged for premium bottles.

Sunflower oil, and the distinction that matters

Standard sunflower oil is the richest of the seven in vitamin E, at 57.3 mg per 100 g, meaning 5.73 mg per tablespoon, nearly half the Swiss nutrient reference value of 12 mg. It is also an oil holding 56.3 g of linoleic acid per 100 g, which makes it prone to oxidation.

The essential distinction is between standard sunflower and high-oleic sunflower. The Codex data reproduced in the 2024 review give 14 to 43 % oleic acid for standard sunflower against 75 to 90.7 % for the high-oleic version. That is no longer the same oil. The high-oleic version behaves like olive oil in a fryer, while standard sunflower degrades twice as fast.

On the label, this usually appears in small print, sometimes only in the ingredients list as “high oleic sunflower oil”. If it is not there, you have standard sunflower.

Coconut oil and the arithmetic of saturated fat

Coconut oil contains 84 g of saturated fat per 100 g, of which 45.8 g is lauric acid. No other common vegetable oil comes close. The NHS advises not exceeding 30 g of saturated fat a day for men and 20 g for women, and one tablespoon of coconut oil supplies 8.4 g.

The argument regularly put forward is that the medium-chain fatty acids in coconut behave differently from animal saturated fat. A systematic review and meta-analysis published in 2025 in Diabetology & Metabolic Syndrome pooled 14 randomised controlled trials from 11 countries, covering 1,049 participants, with interventions lasting 2 to 24 weeks. The finding: virgin coconut oil lowers triglycerides by 12.12 mg/dL and raises HDL by 7.91 mg/dL. No significant effect on other lipid markers, fasting blood sugar, anthropometric measures, blood pressure or CRP. Subgroup analysis even found a significant rise in total cholesterol among participants under 50.

Put plainly: two markers move in the right direction, one moves in the wrong direction in the under-50s, and the rest do not move. It is not a health food, and it is not poison either. It is a cooking fat with a particular flavour whose real advantage is technological: it is solid at room temperature, which is useful in vegan baking for textures that liquid oils cannot produce.

One technical detail few people know: the 2024 review explicitly advises against coconut oil for frying. Medium-chain fatty acids have a lower smoke point than long-chain ones, which is the exception where smoke point becomes relevant again.

A last point on vitamin E: the virgin version holds 12.8 mg per 100 g, the refined version 0.3 mg. Refining removes almost all of it. When a recipe recommends coconut oil for its antioxidants, it implicitly means the virgin version, and the contribution is still only 1.28 mg per tablespoon.

Avocado oil and an authenticity problem

On paper, avocado oil is excellent: 65.2 g of monounsaturates per 100 g, 45.3 mg of vitamin E, a discreet flavour. The problem is not nutritional, it is commercial.

A study published in 2025 in Food Chemistry: X analysed commercial avocado oils to establish authenticity markers based on fatty acid profiles and fatty alcohol esters. Only 40 % of samples met the fatty acid standards. Discriminant analysis showed that the samples with the largest deviations resembled declared blends containing canola or safflower oil. The authors note explicitly that the lack of regulation on avocado oil authenticity has allowed producers to blend it with cheaper oils without declaring it on the label.

That does not mean giving it up, but it does put the price in perspective. If you pay three times the price of rapeseed oil and six bottles out of ten fail the composition standard, the expected nutritional gain per franc spent is thin. The fatty alcohol ester markers do separate extra virgin from refined clearly, at 2,674 mg per kilo against 641 mg per kilo. That is not something you can check in a shop, but it is a reminder that the extraction wording on a label covers very different products.

Sesame oil, a condiment rather than a cooking oil

Sesame oil sits at 40.2 g of monounsaturates and 40 g of polyunsaturates per 100 g, a balanced profile with no particular distinction. Its vitamin E is negligible: 1.1 mg per 100 g, or 0.11 mg per tablespoon.

Its interest lies elsewhere, in flavour. The toasted version develops aromatic compounds that do not exist in the pale version, and a few drops at the end of cooking change a whole dish. It works as a condiment, in small amounts, added off the heat. Heating it destroys exactly what you bought it for.

That is also the use where an oil earns its keep per gram: a properly emulsified dressing gets more raw vegetables eaten than a dry salad does, and our article on building a complete, satisfying meal salad covers the role of fat in making a cold dish filling.

Sesame is a mandatory declared allergen in Switzerland and in the European Union, including in oil form. If you cook for other people, it needs mentioning, and it hides in many Asian sauces and commercial hummus. Our guide to cooking without gluten, nuts or soya covers the substitution logic when several allergens stack up.

Walnut oil, linseed oil and the ALA question

Walnut oil supplies 11.9 g of alpha-linolenic acid per 100 g, so 1.19 g per tablespoon. Linseed oil climbs to 53.3 g per 100 g, or 5.33 g per tablespoon, by far the leading plant source of short-chain omega-3.

Those figures deserve to be set against what the body does with them. The NuEva study, published in 2025 in Frontiers in Nutrition, followed 168 participants across four dietary patterns, with linseed oil supplementation providing 3 g of ALA per day for 9 months against a background of controlled menus. Erythrocyte ALA rose by 22.5 to 38.4 %, EPA by 27.3 to 40.7 % and DHA by 12.8 to 26.0 %, depending on dietary pattern. Conversion improved most in people whose baseline EPA was low: +62.9 % EPA against +12.9 % in the others.

The honest reading of those results cuts both ways. Plant ALA genuinely raises long-chain omega-3 status, DHA included, which contradicts the pessimistic version often repeated. But it does so modestly, and 3 g of ALA a day equals four tablespoons of rapeseed oil or two and a half of walnut oil. If DHA is a priority, our article on choosing algae-based omega-3 supplements covers the direct route, and the one on omega-3 without fish compares the food sources against each other.

Linseed oil is not for heating. It is the oil that reaches the polar compound limit almost ten times faster than olive oil. Use it cold, keep it in the fridge and finish it quickly after opening.

Refining, 3-MCPD and glycidyl esters

This subject is missing from almost every oil guide, even though it sets legally binding maximum levels.

High-temperature refining of vegetable oils generates two families of process contaminants: fatty acid esters of 3-monochloropropane-1,2-diol, known as 3-MCPD, and fatty acid esters of glycidol. The Swiss contaminants ordinance devotes Annex 4 to them, in the version in force since 1 July 2025.

The values worth knowing. For glycidyl esters, the maximum is 1,000 µg/kg expressed as glycidol for vegetable oils and fats intended for the consumer, and 500 µg/kg for those destined for baby food production. Infant formula is capped at 50 µg/kg in powder form and 6 µg/kg in liquid form. For the sum of 3-MCPD and its esters, the limit is 1,250 µg/kg for coconut, maize, rapeseed, sunflower, soya and palm kernel oils and for olive oils composed of refined and virgin olive oil, and 2,500 µg/kg for other vegetable oils.

The practical point fits in one sentence: virgin and extra virgin oils fall outside the scope of these limits, because they do not undergo the refining that produces these compounds. That is probably the strongest technical argument for virgin oils in cold applications, and it is more solid than the usual talk about preserved vitamins.

Storing oils without kidding yourself

The three enemies of an oil are light, heat and oxygen, in that order of practical importance because light is the only one of the three that hits a bottle standing on a worktop.

A study published in 2025 in Foods followed 14 commercial extra virgin olive oils, measured on opening and again after three years of storage. All met international quality standards at the start. After three years most showed clear deterioration, marked above all by a fall in antioxidant activity and a rise in the K232 coefficient. Stability varied considerably between brands, depending on composition and storage conditions.

Three years is longer than most storage advice suggests. The lesson is not that an oil keeps for three years, but that degradation is gradual and depends first on what you do with it: a clear bottle next to the hob ages far faster than a dark bottle in a cupboard.

In practice, buy volumes matching your real consumption. Twenty grams a day comes to 600 g a month for a single-person household, so a litre of oil runs out in roughly six weeks if it is the only one you use. A three-litre bottle bought on offer for occasional use will end up rancid. ALA-rich oils, virgin rapeseed, walnut and linseed, belong in the fridge once opened; the others are happy in a dark cupboard. Our article on the ideal pantry for a beginner vegetarian places oils among the other basic purchases.

Rancidity announces itself by smell before taste: paint, wet cardboard or old peanuts. A rancid oil is not dangerous in the short term, but it brings oxidation products and it ruins the dish. Throw it out.

One habit worth adopting: infusing an oil with herbs, garlic or citrus zest shortens its life rather than extending it, because you add water and plant matter to a medium that was previously dry. Our guide to homemade flavoured oils covers the shelf life and the safety questions those infusions raise, and the article on preserving herbs by freezing, salting or in oil compares oil against the other methods.

If you want to think about oils as part of a broader fat intake rather than as bottles, our article on flax, chia and hemp seeds covers the seeds carrying the same fatty acid profile in solid form, where storage is far less fussy.

What a label is allowed to say

The Swiss ordinance on food information sets, in Annex 13, the thresholds authorising each nutrition claim. Held against real compositions, those thresholds sort the seven oils faster than any sales pitch.

For “high in unsaturated fat”, at least 70 % of the fatty acids must be unsaturated and the energy from those fats must exceed 20 % of the product’s energy. Six of the seven clear it easily: rapeseed 92 %, walnut 90 %, sunflower 88 %, sesame 84 %, olive 84 %, avocado 81 %. Coconut oil sits at 11 % and fails.

For “high in monounsaturated fat”, at least 45 % of fatty acids must be monounsaturated. Olive, avocado and rapeseed pass; standard sunflower, sesame, walnut and coconut do not.

For “source of omega-3 fatty acids”, the product needs at least 0.3 g of alpha-linolenic acid per 100 g and per 100 kcal, and double that for “high in”. Since oils deliver about 900 kcal per 100 g, the per-100-kcal condition is nine times stricter than the per-100-g one, which eliminates candidates that looked like they qualified. Only rapeseed, walnut and linseed clear both bars.

This is a useful exercise to run in front of a shelf. When a bottle says “high in omega-3”, the wording is regulated and checkable. When it says “rich in antioxidants” or “superior quality”, nothing frames it. Our guide to reading and understanding a nutrition label works through that difference between a regulated claim and a free-form sales line.

Five mistakes that come up often

Buying an oil for a nutrient it does not contain. Walnut oil bought for vitamin E and sesame oil bought for the calcium in sesame seeds are the two classic cases. Both are excellent oils for other reasons.

Choosing a frying oil by its smoke point. The useful criterion is the proportion of oleic acid, and the gap in working life between a monounsaturated and a polyunsaturated oil is a factor of two.

Treating coconut oil as an everyday oil. One tablespoon a day already represents 42 % of an adult woman’s daily saturated fat ceiling under NHS guidance, before any other food.

Buying large formats to save money. An oxidised oil costs the price of the whole bottle, since it ends up in the bin.

Heating a finishing oil. Toasted sesame oil, walnut oil and linseed oil lose in seconds of pan heat exactly what justified their price. They go in off the heat.

Adapting to your situation

If you cook for one and want to limit the number of bottles, take virgin rapeseed for cold uses and olive oil for everything else. That covers the Swiss recommendation and most culinary situations.

If you fry a lot, high-oleic sunflower oil or groundnut oil are the best compromises between stability and price, and it is worth keeping the extra virgin olive oil for uses where its flavour counts.

If you follow a vegan diet, the ALA question carries more weight, since there is no EPA and DHA from fish. A tablespoon of rapeseed plus a handful of walnuts covers a substantial share of the intake. DHA is a separate question.

If you cook for young children, the main thing is not to concentrate fat intake on saturated fat. Unsaturated vegetable oils belong there, in amounts scaled to smaller portions.

If an anticoagulant or another long-term treatment is involved, a large and lasting change in fat intake is worth discussing with whoever manages that treatment rather than with an article.

What this article does not cover

No prices in francs appear here, because the gaps between retailers and between formats in Switzerland are too wide for any range to stay useful for more than a few months.

No environmental comparison is made between these seven oils. The balance sheets depend on origin, growing method and transport, and adding them up properly would take a whole article with its own sources.

The composition data come from the French Ciqual table. A Swiss rapeseed oil pressed on a small scale can depart from these values, like any farm product. The orders of magnitude hold; the third decimal does not.

Finally, the meta-analyses cited deal with intermediate markers: cholesterol, triglycerides, fatty acid status. They are not trials on clinical events, and an effect on a marker does not translate mechanically into an effect on long-term health. Our article on reading a nutrition study correctly returns to that distinction.

Frequently asked questions

Can you really deep-fry in extra virgin olive oil? Yes, and it is among the most stable in prolonged frying trials, at 33 hours before reaching the polar compound limit. The usual objection is about smoke point, which is not the right criterion. The valid objections are price and flavour, which becomes more pronounced with heat.

How long does an oil keep after opening? That depends mostly on composition and storage. ALA-rich oils, virgin rapeseed, walnut and linseed, are the most fragile and belong in the fridge. Olive and other monounsaturated oils last considerably longer. Smell remains the reliable test.

Is coconut oil bad for you? The largest meta-analysis available, 14 trials and 1,049 participants, finds lower triglycerides, higher HDL, higher total cholesterol in the under-50s, and nothing on the rest. The point that matters more is its saturated fat content, 84 g per 100 g, held against the daily ceilings.

Should virgin oils be preferred over refined? For cold uses, yes: they retain their phenolic compounds and vitamin E, and they fall outside the legal limits on 3-MCPD and glycidyl esters, which are refining contaminants. For frying the advantage partly reverses, since refining also removes compounds that destabilise the oil under heat.

Does the omega-6 to omega-3 ratio matter? It gives a useful indication for comparing oils with each other: rapeseed sits at about 2.6 to 1, standard sunflower at over 1,000 to 1. But a ratio is calculated across a whole diet, not across a bottle, and the absolute amount of ALA remains the more directly actionable figure.

What about high-oleic sunflower oil? It contains 75 to 90.7 % oleic acid against 14 to 43 % for standard sunflower, which puts it close to olive oil for thermal stability. It is a good frying choice, with a neutral flavour and a price below olive.

Is a smoking oil dangerous? The smoke contains acrolein, which irritates eyes and airways, and cooking fumes also carry polycyclic aromatic hydrocarbons and formaldehyde. A one-off episode is not a health problem; a poorly ventilated kitchen where oil is made to smoke daily is. Turn the heat down and ventilate.

Do you really need seven oils? No. The Swiss nutrition recommendation names two tablespoons a day, one of them rapeseed. The other five oils on this list are bought for flavour, for a specific technical use, or not at all.