Which is the most effective and quickest way to lose weight and keep it off?

Good discipline: You need to get into healthy habbits of eating low calorie foods and exercise daily. Avoid foods that are rich in fats/oils and sugars(minimal or no sweets). Eat plenty of plant-based foods, like..Grains, cereals, fruits and veggies. Focus on consuming more proteins which come with eating, eggs, nuts, fish and low fat milk and no fat yogurt.