The key differences in the diets, according to the review, comes up on the topic of fats: “The main difference between the two diets is the primary fat source. Olive oil is the synonym for MD [the Mediterranean diet] while the ND [the Nordic diet] uses more rapeseed/canola oil.”Though that one ingredients swap may not seem like enough to matter, because they’re used in cooking almost everything it can add up. Olive oil, especially extra-virgin olive oil, is known for its health benefits thanks to high polyphenol content and other beneficial bioactives like omega-9 fatty acids. By contrast, rapeseed oil is less conclusively agreed to have benefits. It’s popular in cooking for its low smoke point, but the way it’s processed means most of it has less essential fatty acids, antioxidants, and vitamins—though cold pressed, extra virgin versions do exist and may be better.Some of the other specific foods emphasized in each diet are also different, due to the vastly different environments from which the diets began. In the Mediterranean, as mentioned, olive oil reigns supreme—but is it any surprise the same isn’t true of the Nordic diet where the colder climate means there’s not a hope of cultivating olives?In the Nordic diet, other key foods include berries, cabbage, apples, pears, root vegetables, oats, rye, and fermented milk—all of which have their own unique health benefits, though the writers of this review are careful to remind us that one isolated component of the diet doesn’t necessarily decide its holistic potential. In the Mediterranean diet, the guidelines emphasize seasonal eating even more and go for cereals, vegetables, and fruit, and low-fat dairy products with only a few servings of fish or white meat per week.The more detailed breakdowns of the diets are also different: when looking at how the different macronutrients should be contributing to daily energy intake, this is how they breakdown (according to a literature review of the Mediterranean diet and the Nordic Co-operation, respectfully). Though the profiles aren’t that different, the key seems to be different emphases on fats and protein.