It seems to me that it points towards stress, which raises cortisol levels. It also points towards unmanaged insulin levels, with the uneven-ness of your eating schedule.
Barry Sears says that the "easiest" piece to fix is what/how we are eating. You can improve upon what you are eating, and you can even improve upon when you are eating. Maybe your schedule does not allow for square meals, but you could certainly manage some zone snacks here and there to gtet you through the longer stretches. It could be as easy as taking along some Zone bars, and then having snacks during your downtime. When you have more time, then you can manage a Zone meal.
You probably can't change your job or your shift very easily, and you might not want to. I know some EMTs, and they are all very committed to their jobs and would not dream of giving it up. It takes a special person to do that type of work! The rest of us really appreciate people who can handle this work. You, being a paramedic, are even more valuable.
You also probably can't change the stress level of your job, so an alternative is to find ways to destress yourself on your time off. Whether it be enjoying a favorite hobby or finding time to do yoga, just find something that you enjoy and DO it!
Working nights does create some havoc in the schedule, but it really isn't any different than days, as far as your eating and meals go. Just re-organize your schedule to accommodate for the meals and snacks. One idea that I have is to eat a good Zone meal prior to starting your shift. At least you will have 4-6 hours of being in the Zone, and if you can time your snacks out, you can stretch out that shift and make it work.