To prevent obesity I limit sugar and alcohol including fruit juices, all the same thing to your liver that will quickly convert them to fat.  Eat good fats including butter to sate your appetite, free sugar will keep you hungry.  Have a good breakfast early in the day and another good meal later so you consume more than sixty percent of daily calories before 5:00 pm.
 
I disregard the doctor's fixation on my total cholesterol number, good triglyceride and euric acid levels are all that matter.  A doctor overzealous about cholesterol can send you down a rabbit hole of issues auto-immune in nature and even metabolic syndrome.  Only doctors in North America have fixated on total cholesterol but this is where heart and stroke disease and diabetes are still at the highest rates.  Statins wont help much and are dangerous.
 
Look for the move 'Fed Up' on YouTube narrated by Katie Couric.