He does have a cup of sustagen every morning with his breakfast.
I usually make sure he has a massive breakfast before his morning tablet.
So he'll have cereal or toast or porridge, then the sustagen afterwards.
He doesn't eat much lunch, just picks, has afternoon tea with no drama, then dinner is touch and go. Somedays he's starving others not.
His diet is high calorie and carbs (when he eats properly).