it takes a while for your body to get into deficit. it's not unreasonable to have 30 hours of nutrition in circulation. then the process of turning fat and muscle into energy can take time also.
you can speed up the process with 40 minutes of good, aerobic exercise every day.
starvation with no exercise will provide results after 5 days or so. Rapid weight loss, breakdown of muscle, malnutrition, heart issues, kidney damage, inability to fight infection, hair falling out ... the list is long.
I went for 500-900 calories per day and exercise which has worked well for me and didn't require hospitalisation.