I found a great site to calculate how many calories you need to eat to lose weight, along with how to track your fat intake and others intakes.
It\'s at
Back Pain and Neck Pain - Causes and Treatments, under \"Eating to Lose Weight\".
There it says: \"If you want to lose weight, multiply your ideal weight by 10. For example, if your ideal weight is 140, your minimal energy requirement is 1400 calories. Next, you need to factor in the calories needed for exercise and activity. Very active people (those who exercise 3 hours or more a week) need to multiply their minimal requirement by 1.5. Moderately active individuals (those who exercise 1 to 3 hours per week) need to multiply their reqquirement by 1.2. Slugs need not factor in additional claories.\"
Example: Ideal Weight is 140. 140 x 10 = 1400 + 1.5 (very active person) = 2100 calories per day.
The article also shows how to calculate your fat intake for nutrition and weight loss/health (only 30% of your calories should be in fat)
Hope this helps.