Living healthy is important for everyone, but omitting fats from your recipes is the quickest path to failure. Removing things from the recipe or replacing fats with random alternatives will change the final results, and often not for the better. Obviously, when you’re making a cake, nutrition isn’t your first priority (otherwise, you wouldn’t be making this cake).
Fats are essential in most recipes, and if your recipe calls for them never leave them out. Imagine trying to make peanut butter cookies without peanut butter. Sure, you will make a cookie, and it might even taste delicious, but it won’t be a peanut butter cookie. Removing fats can keep your dish from baking or even holding itself together properly.