It's really important to eat enough food to fuel your body. Consistently eating under your range can slow your metabolism and sabotage your weight loss efforts. You won't lose faster by eating less than recommended.
First, make sure you're measuring and weighing everything. We (as a general rule) tend to underestimate how many calories we're taking in.
If you're still having trouble meeting your minimums, then Sparkpeople has a great nutrition-boosting article for upping those calories in a healthy way: www.sparkpeople.com/resource/nutrition_art