Avocados are a superfood Yes, avocados are relatively high in fat and calories (138 calories and 14.1g fat in half a medium-sized avocado). But they're also one of the best foods you can eat, packed with nutrients and heart-healthy compounds. Here are five great reasons to eat them regularly. They contain omega 3 which are good fats. Avocados are packed with disease-fighting antioxidants. Avocados are a great source of lutein, a carotenoid that works as an antioxidant and helps protect against eye disease. Avocados also contain oleic acid, a fat that activates the part of your brain that makes you feel full. As well as increasing feelings of fullness, the oleic acid in avocados can help reduce cholesterol levels.