Olive Oil: Friend Or Foe Of Plant-Based Diets?

Olive oil is often touted as a healthy staple in any kitchen, but is it compatible with a plant-based diet?

Olive oil is a processed, concentrated fat extract, and so has lost most of the nutritional value of its original form. When you extract the oil, you leave behind the vast majority of nutrients, and what remains is a very concentrated source of fat and calories with very few health benefits.

The fact is, we do need fats, but they need to be in their original, natural, whole-food form. A whole-food, plant-based, oil-free diet is not a fat-free diet. Plants do contain fat in perfect balance with what we need.

So, while olive oil is healthier than animal-based fats, no oil may be the healthiest of all when it comes to heart health.

Olive oil is highly processed

Olive oil is 100% fat and contains 120 calories and 14 grams of fat per tablespoon. This means that olive oil has the same number of calories per gram as beef fat. As a liquid with a high concentration of fat and calories, and zero protein and fibre, olive oil is very easy to consume in excess.

The process of extracting oil from olives also strips away most of the nutrients found in the original plant, including fibre and other nutrients. Fibre is important as it helps to regulate the body's use of sugars, helping to keep appetite and blood sugar in check. Fibre also feeds the beneficial bacteria in the gut, which are essential for healthy digestion and supporting the immune system.

In addition, olive oil has been shown to cause a constant and significant decrease in endothelial function after meals. Endothelial cells produce nitric oxide (NO) that dilates vessels. The level of dilation is a good indicator of the overall health of vessels. Research has shown that, within hours of ingesting oil, arteries stiffen and their ability to dilate is impaired.

Olive oil is not a health food

Olive oil is often praised for its health benefits, including its high levels of monounsaturated fats, antioxidants, and anti-inflammatory properties. However, these benefits can also be obtained from consuming whole plant foods such as nuts, seeds, and avocados, which provide additional fiber and nutrients that are stripped away during the processing of olives into olive oil.

Olive oil is 100% fat and contains approximately 120 calories and 14 grams of fat per tablespoon. This high-calorie density, combined with the lack of fiber, means that the body absorbs olive oil quickly, leading to weight gain and an increased risk of cardiovascular disease.

In addition, the results of studies on the health effects of olive oil have been mixed. While some studies suggest that olive oil may reduce the risk of stroke and heart disease, others have found no significant link between olive oil intake and improved health outcomes.

Furthermore, the perceived health benefits of olive oil may be attributed to the overall dietary pattern of the Mediterranean diet, which includes a high intake of unrefined plant foods and limited amounts of animal products. The prevalence of these whole plant foods, rather than olive oil alone, is likely responsible for the reduced rates of death from coronary heart disease and certain cancers observed in populations following the Mediterranean diet.

In conclusion, while olive oil may be a better choice than animal fats or other highly processed vegetable oils, it is not a health food. For optimal health, it is best to minimize the consumption of olive oil and other processed oils and instead focus on incorporating whole plant foods into your diet.

Olive oil is high in saturated fat

The high level of saturated fat in olive oil means it can cause arterial damage and the progression of heart disease. While olive oil is a better option than animal-based fats, a plant-based diet with little to no oil is the healthiest option for your heart.

Olive oil is also calorie-dense, with 120 calories and 14 grams of fat per tablespoon. This means it is easy to consume in excess, and it can be difficult for the body to process.

While olive oil has been considered a health food in the past, this is largely due to its association with the Mediterranean diet, which is plant-forward and emphasises fruits, vegetables, and whole grains. However, the higher consumption of fruits, vegetables, and legumes in Mediterranean regions is likely what accounts for the decreased heart disease mortality rates, not the inclusion of olive oil.

In conclusion, while olive oil is a better option than animal fats, it is still high in saturated fat and can contribute to heart disease. For optimal health, it is best to minimise or avoid olive oil and other oils, and instead get your healthy fats from whole food sources such as nuts, seeds, avocados, and olives.

Olive oil is calorie-dense

Olive oil is a highly processed food. The process of extracting oil from olives involves removing the majority of the nutrients found in the original plant, leaving behind a nutrient-void, high-fat, calorie-dense substance. This is true of all oils, including coconut, sunflower, peanut, and avocado oils.

The high-calorie content of olive oil means that it is easy to consume in excess. As olive oil is pure fat, it lacks the bulk and fibre to convey to your senses how many calories you have eaten, making it likely that you will consume more calories than you need.

In addition, olive oil has been linked to vascular injury and arterial stiffness. A 2000 study found that meals prepared with olive oil reduced flow-mediated dilation, a measure of arterial blood flow, by 31%. A more recent study from 2024 found that participants who switched from a low-oil plant-based diet to a high-oil plant-based diet experienced increases in cholesterol, triglycerides, blood sugar, and inflammation.

While olive oil is often touted as a health food, it is important to remember that it is a concentrated source of fat and calories with very few health benefits.

Olive oil is not necessary for cooking

The idea that olive oil is a healthy staple in any kitchen is a costly misconception. While olives are a whole plant food, their extracted oils are not. Olive oil is a processed, concentrated fat extract and has lost most of the nutritional value of its original form.

The same is true for coconut, sunflower, peanut, and avocado oils. Anytime we take a whole food and squeeze out everything healthy, such as fibre and other nutrients, what we are left with is simply concentrated fat. To gain nutritional value, you will need to eat the whole olive (or peanut, sunflower, coconut, avocado) intact, rather than consuming its unrecognisable liquid fat form.

The simple fact is that, though we do need fats, they need to be in their original, natural, whole-food form. A whole-food, plant-based, oil-free diet is not a fat-free diet. The fact is that plants do contain fat in perfect balance with what we need. So where are those vegan fat sources? Broccoli, spinach, kale, carrots, beans, rice, and apples all contain fat.

Even olives, nuts, and seeds should be eaten sparingly due to their higher fat content. The best way to get your needed essential fatty acids is by eating a health-promoting diet derived exclusively from whole natural foods.

Gram-for-gram, olive oil has the same number of calories as beef fat. Coconut oil is 90% artery-clogging saturated fat, and lard is 40%. One tablespoon of oil has 120 calories and 14 grams of fat. A 130-pound woman would have to jog nearly two miles to burn off one tablespoon of oil.

Within hours of ingesting oil, even plant oil, arteries stiffen and their ability to dilate is impaired. All oil, whether from an animal or a plant, causes insulin resistance.

Healthy oil-free cooking requires learning some new methods in the kitchen. For example, you can preheat a pan for a couple of minutes before adding your veggies. If things start to stick during cooking, add a splash of water or broth, depending on the recipe. For baking, baking mats or parchment paper work great.

Frequently asked questions