I think it depends overall on how much you're eating versus your activity level. If you're extremely active and your Calorie targets for weight loss are 2200, a 400 Calorie deficit isn't as significant as if your target for weight loss if 1400 Calories and you're only eating 1000. Cutting too many Calories at once can cause your body to preserve its energy and hold onto as much as possible, so you don't want to cut too extremely because it can be counter-productive.