I've tried various low-carb, low-calorie, and low-fat diets for the past couple of years. Although the Atkins diet is very popular, it made me feel somewhat unhealthy.
The diet plan I'm on right now is the Medifast Diet. The caloric intake is roughly 800-1000 calories. However, it doesn't make my body feel weak. It is a bit of a pricey diet, but there are plenty of coupons available on the internet (i.e. swoopup dot com/stores/deals/Medifast-Diet). You should never pay full price.
My advice is just choose a diet plan which your body reacts positively to. No one knows your body better than you do!

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Rachel

Why not just cut your calories little by little on your own. Its also high protein low carb good luck with that.

My advice clean your diet up plenty of fruits veggies natural starches good proteins, monitor your caloric intake make sure your in a diffientcy.