All cooking oils are processed foods. They are fat extracted from seeds, nuts, or fruit, with the fibre, protein, polyphenols, and other bioactive compounds largely removed. Extra-virgin olive oil is the least processed, retaining meaningful levels of polyphenols that are responsible for its cardiovascular benefits. Other refined vegetable oils have been processed to near-complete removal of everything except the fat. The contrast with whole food fat sources is nutritionally significant.
The Case for Whole Food Fats
A 30-gram serving of walnuts provides approximately 19g of fat alongside 4g of protein, 2g of fibre, 185mg of ALA omega-3, polyphenols, magnesium, zinc, and B vitamins. Walnut oil provides the same fat but without the protein, fibre, polyphenols, or minerals. Whole almonds provide oleic acid fat alongside skin-bound polyphenols, fibre, and a cell wall structure that reduces caloric absorption. Almond oil provides oleic acid but not the polyphenols or the cell wall structure.
The Practical Approach
This does not mean eliminating extra-virgin olive oil, which has unique polyphenol content and is the most evidence-based cooking fat. It means not relying exclusively on extracted oils for dietary fat. Eat nuts and seeds daily as whole food fat sources. Eat avocado regularly. Use tahini (whole sesame seeds ground to paste) in salad dressings and sauces. Eat whole oily fish rather than taking fish oil capsules where possible. These whole food fat sources deliver fat within a nutritional matrix that extracted oils simply cannot replicate.