If someone doesn't know me then I think I can easily hide it. It would go undetected as mental illness I'm pretty certain. My husband is usually the first to notice I'm acting hypo so I don't hide it so well with people who really know me in and out. If I know I'm hypo and want to keep it from someone I might be able to hide it from mom or hubby if I really tried. I might not be able to. I've never tried.