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You probably feel this way because if you cut junk food out completely and suddenly, your body is shocked by the sudden change. Also, junk food has a lot of sugar, which can make you feel energetic, so when you cut junk food out right away your body isn't used to not getting the sugar you used to consume. My advice is to take baby steps. Cut out candy/ice cream, then chips, then soda. etc. until you are consuming less or none at all.
To reach your get-lean goal, you must also follow a get-lean diet, filled with the best foods to burn fat. Why? Even if you work out hard for an hour every day, that still leaves 23 more hours for you to wreck all your hard work in the gym with just one slip-up: a measly handful of chips, a beer with the guys, or a burger at lunch. Diet is a huge, so to speak, part of the fat-loss equation. It's the backbone of your entire plan, the foundation of a hard body.
But before you set out to follow this weight-loss regime, you should know that you are not going to lose pure body fat. Due to the calorie deficit required to burn each kilo of fat, it is not possible to lose 4.5 kg of pure body fat in just one week. Although a lot of the weight you lose will certainly comprise body fat, you will tend to shed kilos by dropping excess water weight from your body. This is because the plan involves lowering your insulin levels and ridding your body of stored carbs that hold water.
I am on day four and I am very discouraged. I don't feel as if I am losing any weight at all. I encourage you to complete the seven days. Don't be too disappointed if you don't lose all ten pounds. Everybody and metabolism is different. Do be careful, however, to follow the diet exactly. Don't eat less food than is recommended in your effort to lose weight as that will throw off the diet's chemistry.