Making a too-drastic cut in your caloric intake is not a good idea. It's only human to think if cutting calories is such a good thing... the more you cut, the better. But, in actuality, the opposite is true.
Extremely low-calorie diets have been around for what seems like forever, yet they do not often lead to permanent weight loss. Often when I see these diets circulating, I find it surprising at just how little people hope they can get by on eating.
I've heard people discussing diets that were as low as 800 calories a day! These dieters are in a danger zone! Not only is a diet this low in calories just plain unhealthy... by making such a major calorie cut, they are actually doing their weight loss efforts a disservice!
Weight loss experts say that cutting your calories down to, or under, 1,000 per day sets you up for inevitable failure. Why? Because when you whittle your caloric intake down this low, you are actually sending your body into "starvation mode" by eating far too little. You're sending a signal to your system that there's a famine... albeit a self-induced one.
Your body wants to maintain your weight when it "thinks" you are starving; therefore, your metabolism will actually slow down. This will inevitably cause you to not lose weight, defeating the purpose of why you cut your calories in the first place!
Another way extremely low-cal diets won't work is because it's nearly impossible to stay on one for very long. In addition to not losing any weight, there are definitely some other unfavorable side effects. Other tell-tale signs that you've gone too low on caloric intake include: headache, weakness, light-headedness and reduced concentration levels.
Eventually you will experience intense hunger and your body will cue you to make up for all those missing calories. After depriving yourself for so long you will be far more likely to overeat and in the end, you will most likely gain weight instead of losing.