:doctor: DiveKitten,
There is much good info on cramps in scuba board, I found this group by doing a search for Scuba diving and calf cramps.
The gist seems to be that diet has not been proven one way or the other to help or hurt. The best advice I got was to put on fins and exercise those muscles. But please do your own research.
Which is my advice to you, exercise is key to weight loss and comfortable diving. Diets do not work. Life style changes do.
I also like to eat, so I do some type of exercise at least six days a week. I try to eat sensible and stay active. Exercise for me is, mountain biking, running, walking, weight lifting and stretching and then deep breathing exercises.
My routines take about 45 minutes a day, I get up early and do it before going to work and generally feel good with a sense of accomplishment for rest of day.
You need to start slow and build up to it, at first it takes dedication and some stern self talk to keep on the program, then after about 30 days you become addicted to exercise, and it becomes easier.
You can search a few "diets" on the internet that I try to follow with moderation, they are simple and make sense, and really do work. Again the key is the dedication at first, till it becomes habit.
The Warrior Diet
The Paleo Diet
The Neanderthin or Neanderthal Diet
Now the benifits are not only will you look better in that bathing suit, but you will feel much better as well, and your diving will be easier and more enjoyable.
Also, "Tank UP" meaning drink plenty of water, all the time.
Good Luck and Great Diving