Low carbohydrate diets are 'in' at the moment, and fat has often been cited as a cause for obesity and poor health. It's true that cutting these things out of your diet will kick start your weight loss, but this is because doing so will reduce your overall calorific intake, not because these things are intrinsically 'bad' for you.
Although being at a calorific deficit is crucial if you want to lose fat, cutting out carbs and fat completely is likely to be counterproductive in the long term; the body needs these things for optimal performance. Carbohydrates are an important fuel, especially if you're working out regularly, and a certain amount of fat is important in your diet to aid fat loss; fat improves cell permeability and signalling, speeding up your metabolism. It's less about quantity than quality - stick to unrefined carbs that provide your body with essential vitamins, minerals and fibre, like quinoa, brown rice, oats, pulses and vegetables. Avoid processed foods, which are high in calories but relatively nutritionally inferior. Eat good fats like those found in avocados, nuts, coconut oil, nut butters and oily fish, avoiding artificial fats found in things like pizza, margarine and fried foods.