The most suitable weight loss intervention for you will depend on your BMI and medical history. If your BMI is over 25, then you should consider weight loss strategies. At a BMI above 30, one is considered obese and above 35 with an associated obesity-related medical condition you would qualify for weight loss surgery. However, if the BMI is 40 or higher, surgery is generally considered the option which will give you a greater and more sustained weight loss than conventional treatment such as dieting, exercise or medication. At a BMI of 40 or above, you would qualify for surgery regardless of any medical conditions.