Lithiated products such as button mushrooms that are cultivated in substrates fortified with lithium (Li) salts, have the potential to provide accessible and safe Li dosing as a treatment for some neurological disorders. However, Li losses sustained during culinary processing are not known. This study of commonly used culinary treatments including various combinations of drying, maceration, blanching (of fresh, deep-frozen and re-hydrated mushrooms) and pickling (of fresh and deep-frozen mushrooms) shows that Li is lost from the edible flesh at varying rates depending on the treatment. Blanching of fresh lithiated mushrooms resulted in a 40% loss, increasing to 77–87% when blanching was followed by pickling. Corresponding losses were similar (47–72%) for non-lithiated mushrooms. Higher losses through the combined treatment relative to just blanching appear to be due to chelating and acidifying effects of the vinegar used. This finding has important dose implications for potential future use of lithiated products.