In addition to @RisingKundaFest’s excellent suggestions, Photosynthesis is helpful for fasting and decreases hunger. It allows your system to use less food and oxygen, and use light as a source of energy.
From the old Teespring description:
This basically causes you to absorb light and use it as a direct energy source for normal functions.
Its even possible to find you use a lot less oxygen and food. You even feel strongly energized, all natural capabilities also seem to grow.
This can be a bit intense for some.