Why are my white mealworms turning brown again?

White mealworms turning brown could indicate several factors, such as stress from temperature fluctuations, humidity levels, or insufficient food sources. Environmental changes, like exposure to light or overcrowding, can also lead to color changes. Additionally, if the mealworms are nearing pupation, their color may change as they prepare to transition into beetles. Ensure they have a stable habitat with proper conditions to maintain their white coloration.