1500 calories for a male! 2000 sounds more reasonable. Do you exercise? If so you'll fall out! Saltines to control blood pressure?????? Nooooooooooooo!!! Sounds like a quack to me!
You need a diet that you can stick with for life. Nobody can live on tuna fish, yogurt and animal crackers. If you HAVE to eat Campbell's then look for the low sodium kind.
I eat four to five times a day. Breakfast, snack, lunch, snack, dinner and maybe a snack. No bread, crackers, chips, lunch meats, sweets, or dairy. It gets easier believe it or not. I eat lots of fruits, grilled chicken, vegetables, low sodium tuna fish, baked potatoes, rice, salads, and treat myself to an ice cream every once in awhile. There is so much you CAN eat. Make the effort and you'll be glad you did.