Theoretically, any type to damage to or dysfunction in the frontal lobe which is affected by ADHD can manifest similar symptoms. There are some nutritional defi

Theoretically, any type to damage to or dysfunction in the frontal lobe which is affected by ADHD can manifest similar symptoms. There are some nutritional deficiencies that can cause a false positive for ADHD(zinc, possibly omega-3). There's also some curious cases of ADHD manifesting due to an very specific type of potassium imbalance. Though AFAIK the only known cases of this have been genetic. It's probably also possible that childhood ADHD could have been "hiding" in childhood, if say your childhood environment was very ADHD-compatible it might not have been enough of a problem to be detected then, but become a problem in adulthood as your environment and responsibilites change. Probably you could make an argument for a diagnosis of adult ADHD in a case like that if there's at least a family history of ADHD.