Im 18 and around 20 stone i've tried many diets and exercises but cant loose weight all family is fat genetics?

20 Stones Lighter: 20 Stones equal 280 lbs which puts u in the obese catagory with a high BMI depending on your height. Ongoing research has shown that obesity is caused by multiple factors and many of these are nor fully understood, including genetics with family history. U should continue on a balanced diet and exercise regimen and discuss surgical option if problem continue to worsen to affect your well being.