This invention relates, inter alia, to various plant-based electrolyte compositions, methods of preparing them and methods of using them. One embodiment concerns a plant-based electrolyte composition comprising a plant-derived electrolyte content high in potassium relative to sodium, and a plant-derived carbohydrate content less than about 6% weight/volume. Another embodiment concerns a method for re-hydrating an individual or preventing dehydration or over-hydration of an individual or for preventing or treating potassium deficiency in an individual, by administering to the individual a plant-based electrolyte composition. The electrolyte compositions can be prepared from sugarcane juice, sugar beet juice, sweet sorghum juice, palm syrup, maple sap, vegetable juice or fruit juice.