Chlorophyll is what gives plants their green color and is responsible for facilitating the process of photosynthesis.
The darker the green color of vegetables the more chlorophyll they contain so choose to eat more of the dark leafy vegetables such as kale, swiss chard, arugula, parsley and cilantro. Wheatgrass, however has the highest content of chlorophyll and so as spirulina and chlorella.
Always choose fresh sources of chlorophyll rather than chlorophyll supplements. Juicing wheatgrass is one of the best options.