Olive oil

Olive oil is a pure fat: 100 g of fat for 899 kcal, with no protein or carbs. Rich in monounsaturated fatty acids and an emblem of the Mediterranean diet, it supports cardiovascular health and hormone production.

Very caloric, it is measured precisely: one tablespoon (~10 g) already provides ~90 kcal.

Raw as a dressing (salads, vegetables, dishes), it best preserves its qualities. For cooking, it handles low to medium heat; extra-virgin olive oil is the highest quality. A drizzle is enough to enrich a dish with healthy fats.

When bulking, oil is a simple, concentrated way to add calories (a drizzle = a lot of energy). When cutting it stays healthy but is dosed to the gram: this is often where 'invisible' calories hide.

Extra-virgin olive oil is cold-extracted, unrefined: it is the richest in polyphenols (antioxidants) and in flavour. Save it for raw dressing, where these qualities show. For cooking, a more neutral olive oil does the job perfectly.

Light and heat oxidise it: keep it in a dark bottle, cool and away from light. An oil that goes rancid loses its taste and value — buy sizes you finish within a few weeks.

Around 70 to 75% of the fatty acids in olive oil are monounsaturated, mostly oleic acid. The rest is split between a little saturated fat (around 14%) and polyunsaturated fat (around 10%). This balanced profile, stable under moderate heat, is what earns it such a good reputation among nutrition professionals.

It also supplies vitamin E and, for extra-virgin, polyphenols. Keep perspective though: these protective compounds are present in small amounts. It is not a supplement, it is a quality fat that advantageously replaces fats richer in saturates on your plate.

The smoke point of extra-virgin olive oil sits around 190 to 210 °C (375 to 410 °F), which is more than enough to pan-fry vegetables, sear fish or soften an onion. If the oil clearly smokes, the pan is too hot: lower the heat, wipe it and start again, because burnt oil tastes acrid and loses its qualities.

In the oven it works very well up to 180-200 °C (350-390 °F), for instance for chicken or roasted vegetables. For deep-frying, another oil is preferable, and above all avoid this kind of dish when you count calories: the bath soaks up a considerable amount of fat.

The most reliable tool remains the kitchen scale: place the pan or bowl, zero it, then pour the oil until you hit the target weight, 5 g, 10 g or 15 g. By eye, people almost always pour two to three times more than planned, which easily adds 150 to 200 extra kcal without noticing.

An oil sprayer or a kitchen brush lets you grease a pan with only 2 to 3 g. On a good non-stick pan, half a teaspoon is often enough. Also remember to weigh the oil in your salad dressings: it is the most underestimated item in a food diary.

There is no magic dose. A simple guideline: fat should make up roughly 20 to 35% of your calories, often 0.8 to 1 g per kg of body weight. One to three tablespoons of olive oil per day (10 to 30 g) fit easily into that budget, on top of the fat already found in meats, eggs or nuts.

If you are cutting and your fat target is already filled by oily fish or eggs, reduce the oil to a measured drizzle. In a hard bulk, it is on the contrary a handy tool for gaining 200 to 300 kcal without adding volume to the plate.

Classic mistakes: pouring by eye, leaving the bottle next to the hob, heating until it smokes, or buying a huge tin that goes rancid before it is finished. Another frequent confusion is to believe a 'light' oil contains fewer calories: it does not, all oils provide about 900 kcal per 100 g.

As for alternatives, rapeseed (canola) oil provides more omega-3 and suits dressings well, avocado oil tolerates high heat, and a little clarified butter is fine now and then. The ideal is to vary sources rather than bet everything on a single oil.

It lifts the Chicken, basmati rice and broccoli bowl, softens the Chicken and crunchy vegetable skillet and adds body to the Chickpea and tuna salad. In the Salmon and quinoa bowl or the Cod with brown rice and zucchini, a raw drizzle at the end enhances flavour with no need for an industrial sauce.

Practical tip: make your own dressing with 10 g of oil, lemon, mustard and herbs. You control the calories, avoid the added sugars of store-bought sauces and get a tastier seasoning.