Over-indulgent is an adjective that describes someone who is overly permissive or indulgent, especially when it comes to pleasures like food or drink. Antonyms for over-indulgent would include words that describe someone who is disciplined or moderate in their habits, such as abstemious, restrained, or self-disciplined. Other antonyms might emphasize a lack of indulgence altogether, like austere, abstinent, or frugal. In contrast to over-indulgent, these words suggest a sense of self-control and restraint, indicating someone who is responsible and mindful of their actions. Therefore, one should strive for a balance between indulgence and restraint to maintain a healthy and fulfilling lifestyle.