I find most of our patients with IC have trouble with weight, but more often than not it is that they are not assimilating their nutrients properly and it is causing weight loss rather than weight gain. There are some patients however with the opposite problem. Working with the Microbiome in our experience is key to re-establishing health and that in turn effects everything including the metabolism. I just came accross this article and it is dealing with the issue from a different approach which I thought was pretty interesting: https://www.endocrine.org/news-room/current-press-releases/magnetic-brain-stimulation-causes-weight-loss-by-making-gut-bacteria-healthier