I mean… I wouldn’t do this. But millions live on a similar diet every day (minus the multivitamin). Sugary cereal for breakfast with fruit flavored “juice”, a fried chicken sandwich for lunch (kudos for the chicken, but then its white bread, white flour, soybean oil, and flavored soybean oil) plus a soda, and finally, say, boxed mac and cheese for dinner with a canned margarita to take the edge off.

Day to day, you will adapt and how you feel on the diet will start to feel “normal”. But you will get fat, be at higher risk for any number of health issues in the long term, and will likely feel depressed. But relative to, like, starving to death, you’ll be pretty healthy.