Healthiest and unhealthiest oils to cook with

A really interesting article from Sue Quinn at the Telegraph discussing the healthiest and unhealthiest oils to cook with. And what the experts thoughts are on Rapeseed Oil…

Extracted from Telegraph 28th August 2024…

Oil is the ultimate kitchen staple, used for everything from sautéing and deep frying to roasting and pouring into salad dressings. Extra virgin olive oil is renowned for its health benefits – but is it the right choice for every culinary task? The answer is complicated.

When you’re frying or heating oil to a high temperature (usually around 180C), it breaks down in a process known as oxidation. Fat molecules react with oxygen in the air to form substances called aldehydes and epoxides, types of lipid oxidation products (LOPs). Both are toxic and can be transferred to food.

‘‘LOPs have been linked to a range of health concerns including cancer, heart disease, birth defects, raised blood pressure and inflammation,’’ says Prof Martin Grootveld, a bioanalytical chemist at De Montfort University who has studied cooking oils for 30 years.

The hotter the oil gets, the more of these chemicals are produced, especially at the ‘smoke point’ – the moment at which it starts to burn and smoke.

What many people don’t realise is that unsafe levels of toxins are also generated below the smoke point, too. The risk of this happening is measured by the peroxidative susceptibility index (PSI); the higher the PSI, the more readily it degrades. Some oils oxidise and go rancid at room temperature, which is why it’s important to pay attention to the best before date on the bottle.

So, how do you know which oil is best for the job? We asked the experts. Note: the health score reflects an oil’s healthiness when used for cooking.

RAPESEED OIL

Rapeseed oil contains virtually no saturated fats and is high in healthy MUFAs, as well as beneficial plant compounds (although this varies depending on how it was harvested, stored and processed). It’s also rich in vitamin E, as well as omega-3, 6 and 9 fats, which support brain, heart, and joint function.

Rapeseed oil doesn’t degrade as easily as PUFA-rich sunflower oil. However, Prof Grootveld says. “It’s fine for frying but as with sunflower oil, don’t use the same batch more than once”.

Like olive oil, rapeseed oil is available refined and unrefined. In the UK, oil labelled ‘vegetable oil’ is usually refined rapeseed oil and has almost no flavour. Unrefined rapeseed oils are often labelled ‘cold-pressed’, ‘premium’, ‘virgin’ or ‘extra virgin’, and have a more pronounced, sometimes nutty flavour.

Calories per tablespoon: 124

Typical smoke point: 205-230C

Suitable for: Deep frying, sautéing, grilling and baking. Use cold-pressed and virgin versions for dressings.

Healthiness: Very low in saturated fat, high in healthy mono-unsaturated fat which can help reduce cholesterol levels. Also contains essential polyunsaturated omega-6 and omega-3 fatty acids.

Health score: 4 out of 5