Using a potato as a battery by inserting different metal pins can potentially affect its nutritional value and safety. The introduction of metals like copper and nickel may lead to the formation of salts within the potato, which could be unappetizing and potentially harmful. The discussion highlights that trace metals can cause health issues when ingested in high amounts, with copper being a particular concern due to its common presence in cookware and its tendency to leach into food, especially when cooking acidic items. Long-term exposure to excessive copper can lead to toxicity. The conversation also notes that while electricity itself does not harm the potato, the presence of metals poses risks. Additionally, there are concerns about unlined copper cookware, which can further contribute to metal leaching. Overall, the consensus is that inserting metals into food items like potatoes is not advisable due to potential health risks.