What if I told you that eating a ton of fermented foods could help treat depression? Or obsessive-compulsive disorder? Or borderline personality disorder? Sounds pretty appealing, right? The GAPS diet claims to do just that. But as a registered dietitian with a focus on digestive health—one who’s all about using food to help manage symptoms and promote overall wellness—this set off my spidey sense. So I had to look into it further.