While it's difficult to pinpoint exactly why some women experience food cravings, obstetrician Dr Cindy MP Duke says that some probably have a physiologial explanation (such as nutritional deficiencies and hormonal changes). But others can't be explained, possibly because research on the topic is lacking.
This is a companion discussion topic for the original article at https://patient.info/news-and-features/what-your-pregnancy-cravings-could-mean