Basically junk food, stuff like colas, crisps, cakes, bottled juices, cereals, and processed meats. Also eat in an 8 hour window only
My last fast was 60 hours, just water. That was my third one I have done, takes some willpower, but it's great for the body, apparently
"When you fast, your body stops using glucose for fuel and starts to metabolize fat. This helps drive blood sugar and insulin levels down, reducing your likelihood of gaining weight and developing diabetes or heart disease. Intermittent fasting also increases the release of human growth hormone, which regulates your metabolism and preserves muscle mass while burning fat"
https://www.sutterhealth.org/health/digestive/fasting-what-you-need-to-know