Cravings and diet

Hi everyone, ive been asked by the Dr. to visit an nutrionist for a diet to keep me and the baby which is only 5weeks healthy. Reason is I have weak cervix due to two surgeries. This situation took me to loosing my first baby last year at 11 weeks and 3 days. This time everything is already being planned since day 1 I knew I was waiting with lots of instructions, medications, shots and considering stitching my cervix a bit eatlier than what its use to. Two things worry me, the stitching before because first trimester is unsecure and the diet. Im pregnant, I have cravings. This has me on mood swings. Any advice of how you gurls control your appetite, besides your willpower.