Consistently Under Budget. Do I need to be in range?

[Extra]

I'm not what I would consider overweight, but I would like to get slimmer. I eat fairly healthy and not very much, and I've noticed that even at the Hard level of a food plan I'm consistently struggling to not be under budget.

It seems counter intuitive to me to eat extra in order to lose weight, so my question is basically is being under budget a bad thing? If I go under budget on a project at work but still get the job done that's not a problem right, so is it the same here? Or should I be putting in effort to make sure I eat enough calories to be within my budget.

[A_Lurker]

@Extra - define how much under budget.  A couple of hundred calories I wouldn't worry about.  The calories burned equation is just a guess, but if you're starting I'd consider it close until you know better.  Usually when people are closer to a normal weight though they might not want to be eating 1000 calories under even.  Myself, if I eat too little my weight loss does in fact slow down.  It's way more complicated than that - I'll so my sleps slower, and with less effort, burn fewer calories, etc. - but still quite true.  Use the calculator here:  http://www.fat2fittools.com/tools/bmr/

This is what your body burns if you do nothing all day.  Most people don't realise how high it is.  With the exception of doctor supervised weight loss it is normally recommended that you don't eat less than your BMR on a regular basis.  Also, I think we've lost sight of what a portion is.  I swear the apples they sell as 'small' are closer to medium.  The regular looking apples are large.  This doesn't make a big difference, but then heap a Tb of peanut butter and the difference is bigger.