Seems to be a logic problem…

>Keto is a fad >no it’s a diet developed in clinical setting been around more than 100 years >I don’t know why people bring up that its not relevant >yes, it directly contradicts what OP said >it’s no mutually exclusive, sure it’s been around 100 years, but it’s a far and won’t be around in 10

>Are there diets that have life long adherents over the last 100 years that have been studied? >show your studies

I think someone like you would be better off googling. You should easily find studies supporting as many as 70% of epilepsy patients who are treated with keto as children can get off of keto after 5 years without any seizures and no longer need any medication. You should also be able to find studies of long term keto diets, ‘long term’ as defined within the studies themselves, covering various types of individuals and get yourself a healthy perspective on the overwhelmingly positive outcomes and to a fat lesser extent the negative outcomes.

Good luck!