Plants have it so easy: they look pretty and hang out in the sun, and from that alone they get all the nutrients they need. All the while we forage for our food, track it down, move, and generally struggle a lot more (you know, when Netflix isn’t involved).
What would it take to make a human into a photosynthetic organism, subsisting more or less entirely on sunlight? A lot more than you might expect.
For starters, a gigantic tree only uses about 200 calories a day, so we’d need to be more efficient than just about any plant out there. Our cells would be different, as would our skin. Basically our whole physiology would have to change, and that would limit what we’re actually able to do with all that free time we’re not using to hunt and gather.
Watch this video, from ACS Reactions, to hear all about it: