From brain, to gut, to heart health, there are many ways extra virgin olive oil (EVOO) supports our wellbeing due to its healthy fat profile and abundance of bio-active compounds.^1-3 As EVOO is ~98% fat, it is full of energy and has often sparked the question – will following an eating pattern rich in EVOO cause weight gain? Whilst body weight is not an accurate indicator of health in isolation, drastic changes in weight can impact everyday life, so if you’re curious, let’s take a closer look at the evidence and investigate!

What does the research tell us?

Consuming 2-3 tablespoons of EVOO each day as a part of a balanced plant-based diet is associated with a lower risk of chronic disease, may improve mood, quality of life and may assist in weight maintenance.^1-4 Poulimeneas D et al 2020 sought to investigate whether adhering to a Mediterranean-style eating pattern may support maintaining weight loss long term. It was found that high adherence was associated with a 2-fold increased likelihood of maintaining weight loss when compared to the other participants in the study.⁵ Amongst other plant-based foods, olive oil was highlighted as a key dietary contributor to this outcome, positively supporting health without creating big changes to your body composition.⁵

Guasch-Ferre M et al 2025 is another study that investigated if weight gain occurs when trying to follow balanced diets higher in olive oil, with the goal of improved cardiovascular health. Over the course of 20-24 years, this study also observed an inverse relationship between increased olive oil consumption and bodyweight over the follow up period – begging the question, maybe we shouldn’t be removing all foods from the diet that are higher in calories?⁶ Especially if they are full of healthy fats, bio-active compounds and are backed by research (a specific cold-pressed oil comes to mind).

Turning the focus away from calories  

The evidence above, alongside many other papers, supports that EVOO should not be disregarded as an important tool for weight maintenance because it is high in energy. As consistency is key, the way EVOO can elevate the flavour profile of vegetables, legumes and whole grains could be a reason why studies have shown improved long-term adherence to a Mediterranean-style diet with the goal of weight maintenance over traditional low-fat diets.^{4, 7} Adding pepperiness, creaminess and a medium for foods to caramelise, cooking with EVOO can bring the focus back to prioritising eating fresh whole foods that taste delicious, instead of calculating calories.

So, does EVOO cause weight gain?

The short answer is… if you are consuming EVOO as the main fat source in a balanced diet, research shows, no it does not! From the health benefits to the culinary benefits of cooking with EVOO, there is no reason to shy away from using this beautiful oil daily.  

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