Is Olive Oil Good for Keto? What the Science Actually Says

At a glance:

Extra virgin olive oil fits into a keto diet because it is naturally low in carbohydrates and provides a source of fat that can be used across everyday meals. Research into olive oil specifically within keto diets is still developing, but current studies highlight the importance of considering the overall quality and type of fats used.

Stock a keto pantry, and you’ll often find the same fats appearing again and again: butter, coconut oil, MCT oil and other high-fat staples. Extra virgin olive oil rarely makes the list, which is a little strange, because it's been the primary fat in Greek diets for thousands of years - long before anyone called it a macro.

With our roots in Greece, it's no surprise that extra virgin olive oil has always been central to the way we think about food; simple ingredients, seasonal produce and cooking methods passed down through generations.

Of course, a long history of use doesn’t automatically tell us what the science says. That’s why researchers have spent the last few decades looking more closely at olive oil as a dietary fat, including its composition and the naturally occurring compounds found within extra virgin olive oil.

In this article, we’ll explore what the research says about olive oil and keto, where EVOO fits into a low-carbohydrate approach, and why the quality and characteristics of the oil you choose can matter.

Why fat quality matters more on keto

A keto diet cuts carbs hard and leans on fat instead, pushing your body to burn fat for fuel rather than glucose. With fewer carbs on the plate, the body can enter ketosis - a state where the body breaks down fat and produces ketones (a chemical) to use as an alternative fuel source.

Once you're in ketosis, the fat on your plate becomes a much bigger part of everyday meals, which means the fats you choose naturally matter more. And that’s where extra virgin olive oil comes in. 

While many keto-friendly meals focus on adding fats to meals, the fats you choose can also bring something special to the table. 

Olive oil adds its own flavour and character, helping turn simple ingredients into something a lot more enjoyable. Whether it’s drizzled over roasted vegetables or used to finish a salad, a good olive oil can change the way a meal comes together.

Is keto even one of the best diets to go on?

If you’re wondering what are the best diets to go on, the answer depends on who you ask. Keto has become popular for many different reasons, but it’s not the only way to approach food. Everyone’s eating habits look a little different, and the best diet is usually the one that fits naturally into someone’s lifestyle.

The UK government’s Eatwell Guide sets out the government’s eight guidelines for a healthy diet, encouraging a balance of different foods - including plenty of fruit and vegetables, fibre-rich carbohydrates, protein sources and unsaturated oils in moderation. 

Keto deliberately breaks from it by cutting carbs right down, which means the fats filling that gap have a lot more to bring to the table than they would on a normal plate.

Is olive oil actually keto-friendly?

Olive oil is essentially 100% fat with zero net carbs, so it can't interrupt ketosis in any meaningful way. One tablespoon contains around 120 calories, entirely from fat. On a standard keto approach where around 70-75% of your daily calories come from fat, that's a useful amount of your daily target in one spoonful.

For someone eating around 2000 calories a day, that usually works out at roughly 155-165g of fat per day, and a couple of tablespoons of olive oil makes a real dent in that without any effort.

But "keto-friendly" is a low bar - butter, lard and vegetable oil clear it too. Given how much of your daily intake is going to be fat, it's worth questioning what else that fat brings, rather than treating all keto-friendly oils as interchangeable.

Why olive oil is a natural fit for keto

Olive oil fits naturally into a keto way of eating because it contains virtually no carbohydrates and is rich in oleic acid, a monounsaturated fat. But while the basic fat profile is similar across many oils, what sets extra virgin olive oil apart is what comes alongside the fat - including naturally occurring plant compounds such as polyphenols.

From a keto perspective, all of these options are very low in carbs. The choice comes down to more than just whether a fat fits your macros - flavour, how you use it and what naturally occurs within the oil all play a part. This is something we explore in more detail in our guide to high polyphenol olive oil.

What we know so far about olive oil and keto

So what does the science actually say about olive oil and keto? Well, research is still fairly limited - although the benefits of olive oil in the diet have been investigated in a variety of nutritional studies. That said, the studies that do focus on keto are interesting.

These findings are shared for general scientific information only and are not authorised UK health claims. As with any area of nutrition research, individual results can vary, and further studies are needed to confirm these effects.

One study published in Neurological Sciences looked at an olive-oil-based ketogenic diet in children with drug-resistant epilepsy over 12 months. The researchers found changes in blood fats, including cholesterol and triglycerides, showing that the type of fat used is only one part of a much bigger dietary picture.

Other research has explored Mediterranean-style keto diets that include extra virgin olive oil alongside foods such as fish, vegetables and lean proteins. A pilot study published in Nutrition & Metabolism followed 106 adults for six weeks and reported changes in areas including body weight and several other cardiovascular markers. 

However, larger and longer-term studies are still needed to understand the effects of different keto approaches.

What this research tells us is that keto is not just about eating more fat - the type of fat and the quality of the ingredients matter too. A good extra virgin olive oil, like our very own November Polyphenols, can add depth and character to everyday meals while fitting naturally into a lower-carbohydrate way of eating.

How to use olive oil in a keto kitchen

One of the best things about extra virgin olive oil is how easily it fits into everyday cooking. In a keto kitchen, it can add richness and flavour to simple, low-carbohydrate ingredients without taking over the dish.

Try drizzling it over grilled fish, eggs or avocado, mixing it into a herb-filled dressing, or using it to finish dishes built around low-carb vegetables, meats and seafood. A small pour can add depth and bring all the flavours on the plate together.

For generations, olive oil has been at the heart of Mediterranean cooking because it helps simple ingredients shine. That same approach works beautifully in a keto kitchen: choose good ingredients, keep things uncomplicated, and let the flavours do the talking.

Simple keto meal ideas using MasWorth EVOO

• Breakfast: Fried eggs, finished with a drizzle of MasWorth Family Groves and flaky salt, avocado on the side.

• Breakfast: Avocado topped with poached eggs, chilli flakes and a generous pour of November Olive Oil for a fresh Mediterranean twist.

• Lunch: Tuna, cucumber, olives and boiled eggs dressed with lemon and EVOO - simple ingredients, no complicated prep.

• Lunch: Grilled halloumi with leafy greens, herbs and a drizzle of November EVOO, bringing plenty of flavour to a simple low-carb plate.

• Lunch: A proper Greek salad (cucumber, tomato, olives, feta, red onion) dressed with just November Polyphenols and lemon, no bottled dressing required.

• Dinner: Lamb chops with roasted aubergine, courgette and herbs, finished with a little more EVOO at the table.

• Dinner: Sea bass, salmon or chicken thighs cooked in Family Groves, finished with a fresh drizzle of November Oil at the table to bring out the flavour of the dish.

• Sides: Roasted courgette, broccoli or peppers, tossed in oil before roasting and again once they're out of the oven.

• Sides: Cauliflower mash, sautéed spinach or roasted broccoli finished with olive oil, sea salt and fresh herbs.

• A snack: A few olives, feta cubes and cucumber slices with a little dish of November for dipping.

• A snack: Boiled eggs with flaky salt, cracked pepper and a drizzle of Family Groves.

How much olive oil to use on keto

Keto cooking doesn’t need complicated recipes or a long list of ingredients - EVOO is an ingredient to enjoy naturally as part of your cooking. As a general guide:

• 1-2 tbsp (15-30ml) over salads, low-carb vegetables or dishes finished at the table

• Around 1 tbsp for everyday cooking, such as eggs, fish or sautéed low-carb vegetables

• Add it cold or towards the end of cooking where you can to make the most of it - EVOO is more heat-stable than people assume, but prolonged high heat isn't kind to polyphenols

When you’re using olive oil more regularly, the bottle you choose starts to matter. A high-quality EVOO is made from carefully selected olives and extracted in a way that helps preserve the qualities that make it special. 

For keto cooking, choosing an EVOO isn’t just about finding an oil that fits your macros. It’s about choosing one with the flavour, quality and character that you'll look forward to using every day.

Making olive oil part of your keto kitchen

There’s no single “best diet plan for beginners”, and keto is just one way of approaching food. But if you do choose a keto way of eating, the fats you use become a bigger part of your everyday meals.

Extra virgin olive oil fits naturally into that picture. It brings no carbs, plenty of flavour and a place at the table that goes back generations. Choosing a high-quality EVOO like our MasWorth Family Groves EVOO or November Polyphenols Olive Oil is about finding an oil you genuinely enjoy using - not just one that fits the numbers.

Want to get more from your olive oil? Explore our guides on how to taste and appreciate olive oil properly and why freshness matters when choosing EVOO. 

Scientific and nutritional information disclaimer

The information on this website is provided for educational and informational purposes only and summarises published scientific research and general nutritional information relating to olive oil and olive polyphenols. It is not intended as medical, nutritional or dietary advice and should not be relied upon as a substitute for advice from your doctor, registered dietitian or other qualified healthcare professional.

Scientific studies reflect the findings of their respective authors and should not be interpreted as evidence that the same results will occur for every individual or from the consumption of any particular product.

Any health claims made in relation to our products are limited to those expressly authorised under applicable UK and EU nutrition and health claims legislation.