Losing weight, but very few inches

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Hello there,

So I've lost roughly 18lbs so far since I started eating better 5 weeks ago, but I've only lost about 2 inches off my waist...maybe.

I started out doing Phase 1 of the South Beach Diet for 3 weeks, and then I moved into Phase 2. I've upped my daily carbs to roughly 100 or so per day (around 25% of daily calories) and have been sticking to more protein daily. I try to get in at least a half hour of walking in while I'm at work every day and I do crunches every other night before bed; still not seeing a real difference. I notice that overall I'm looking more trim, but I really am wanting to lose this belly fat. I can't find pants that fit without the legs being huge parachutes.

I have my calorie goal set up to lose at least 1.5lbs a week (if I hit it, I'm almost always under)

Do I need to try to get more cardio in every week, maybe some more core exercises? Has anyone else had this issue as well?

Thank you all!