Shikamaru would see it as another one of Naruto's troublesome behaviors. He'd sigh and say something like 'What a drag, Naruto. Can't you eat like a normal person?' But deep down, he'd also be a bit intrigued and might end up getting used to it over time.
Sakura would probably be both disgusted and amused at the same time. She might scold Naruto for being so unhygienic at first, but then laugh at his silly antics.
Sakura would be very worried. She would immediately try to find a medical solution, using her knowledge as a medical ninja. She might be disgusted by the worms at first, but her concern for Naruto would override that.
His friends from Team 7, like Kakashi, would feel responsible for Naruto's situation. Kakashi would likely use his resources to find a proper shelter for Naruto. Shikamaru and the others might come together to form a sort of support group for Naruto. They would pool their resources, like money and food, and also try to cheer him up by sharing stories and jokes.
A plot could involve Naruto being cursed by an enemy. As a result, he can only consume food by using his whole body. At first, he's embarrassed and tries to hide it from his friends. But then he realizes that this new way of eating gives him an unexpected advantage in battle. For example, he can quickly consume a large amount of food to boost his energy during a fight.
His friends would be in shock. Kakashi would take charge of the situation. He would gather all the information about what Naruto was doing before he disappeared. Naruto's friends like Choji and Ino would use their respective skills to help in the search. Ino could try to use her mind - reading jutsu on people who were around Naruto before he disappeared. They would all be determined to find Naruto because he is an important part of their team and the village.
Sakura might be initially suspicious. She is a smart girl and would wonder about the butler's intentions. She might keep a close eye on him to make sure he doesn't harm Naruto in any way.
Sasuke, who has his own complex relationship with Naruto, would probably be in denial at first. He's seen Naruto as this strong - willed person, and the idea of him having schizophrenia would be hard to accept. But as time goes on, he would become more protective. He might train Naruto in ways to control his mind during the episodes, using his own experiences of mental discipline. As for Kakashi, he would be empathetic. He has his own traumas, and he would do his best to support Naruto, maybe sharing his own stories of dealing with difficult mental states.
Sasuke might be initially suspicious and keep his distance. He's always been cautious, and this strange new development would make him even more so.
Sakura might be initially shocked and heartbroken. She has been Naruto's friend for a long time, and his sudden departure would leave a big hole in her life. She might try to convince him to stay at first.
Hinata would be heartbroken. She has always loved Naruto deeply. She would probably be in a state of shock at first and then mourn for a long time. She might also try to keep Naruto's legacy alive, perhaps by teaching his ideals to the next generation of ninja.
Sakura would probably be a bit skeptical at first. She might worry that Naruto is getting distracted from his ninja duties. But once she sees how passionate he is, she would support him and might even help him with his training regime, using her medical knowledge to make sure he's in top physical condition for racing.