Not scientific, but this is tried and simple tip from traditional Ramadhan fast-breaking in Tunisia. We start with some dry fruits (usually dates) and olive oil (or butter), then some soup. I think the chewing first gets your body ready and the soup is there to ease the stomach into whatever your regular diet is.

Thank you.

Are there specific soups typically used? Or just any soup will do?

Start small with easy to digest foods, and reintroduce food slowly.

> Any patient with negligible food intake for more than five days is at risk of developing refeeding problems.

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2440847/

Thank you!