You body needs glucose to heal (proteins and fats play a great role too, dependent on the injury.) Now it doesn't have to be carbohydrates, but those require the least amount of energy expenditure for your body to use. And pound per pound, your brain uses more glucose to function on a daily basis than any other organs. It makes sense but they're not suggesting loading up on sugar tablespoons at a time. My suggestion would be things like sweet potatoes, carbohydrate dense but not straight sugar.
Glad you're doing ok though!