Adding fat to your smoothie will, of course, add some calories. But healthy fats offer up more than that – you can also pick up some vitamins, minerals, essential fatty acids and fibre along the way.
Seeds like flax, hemp, chia or sunflower seeds add a bit of texture to your smoothie, and give a little boost of minerals (especially copper and zinc) and omega-3 fatty acids.
Nut butters such as almond, walnut or pistachio, also contribute zinc and copper, along with some protein and fibre, too.
Avocado adds a silky-smooth add-in to smoothies, and provides the same healthy fats found in olive oil along with some vitamin E.