Lactate plays a critical role in cell metabolism and disease development. Under conditions of hypoxia or high-intensity exercise, cells use the glycolytic pathway to convert glucose into pyruvate, which is then reduced to lactate to quickly obtain energy. The traditional role of lactate is being redefined, as it is not only a provider of energy but also an important signaling molecule that regulates cell physiological functions, including histone lactylation modification, which affects gene expression. However, excessive accumulation of lactate is associated with the development of various diseases, such as liver disease, cancer, and cardiovascular disease. Research has also found that small-molecule drugs can regulate lactate levels, providing new possibilities for treating related diseases.