A medical alert bracelet isn't really supposed to be for people to "take notice", like in a restaurant or something like that. It's intended to be for emergencies, like someone is unconscious or disoriented. The emergency personnel (EMTs, etc.) can see the information on the bracelet and treat the person accordingly. For example, some people who are having a diabetes emergency can act/look like they're drunk. If a police officer thought the person was drunk and just took them into the local jail the person could die. But if the bracelet alerts them to diabetes the police can call the EMTs immediately.
So personally I would never wear one for celiac since it's not an immediately life-threatening condition. If I'm unconscious from something else the last thing the medical workers are going to do is feed me food with gluten.
I agree regarding medic alert bracelets for adults....as stated I wear mine as I have severe breathing difficulties and have had three anaphalaxis episodes which have worsened over time.
I respectfully disagree for children.....my Grandson is five - gluten-free for four years and completely able to explain his dietary needs and safety to any adult -- yet had explosive diarhea repeatedly at school for the first three months of Kindergarten. If a bracelet will remind teachers and volunteer parents of the serios nature of his situation (doctors orders have been provided to the school) - then this is another valid use of these bracelets.