I'm on the same diet and I have plenty of energy. You have to remember to take your vitamins every day and I suggest a couple of calcium pills to help with sugar withdrawals. Drink 4 to 8 glasses of water a day and walk a little. After the first week I had bad sugar withdrawals and I was fit to be tied. It will effect you because people don't realize how addictive sugar is to your body. 1400 calories at least.DO NOT worry about calories on this diet in the beginning. Only worry about carbs. Eat as much meat and cheese as you want until you get past the first 2 weeks. After that you can adjust your caloric intake.