The girl on the left is toned, healthy, fit, has a low body fat percentage and looks great!
If you diet alone, this will lower your metabolic rate, put your health at risk and keep you eternally skinny looking, but feeling fat and squidgy.
It is super important that you lift weights, to keep your muscles working and burning calories at rest. This is the only way you will keep your metabolism high!
Always aspire to be healthy and fit, it’s good for you mind, not just your body, you’ll feel great and never feel hungry! A combination of weight training mixed with cardio is the best and only way for an effective workout that will keep your metabolic rate high. That and of course a healthy diet!