unless you have a chronic illness or take regular medications you don't really need medical supervision when you're starting a weight loss program even if you're obese. there are hundreds of diet books at your local bookstore and i doubt that following any of them would cause any harm. while a really extreme low-calorie diet – 500 calories or so – could be risky nobody can really stick to that anyway. however i do think you should include your doctor as part of your support system and ideally as a lifestyle coach. your doctor can help you monitor your progress as well as provide external accountability.
do i need to see a doctor before starting a weight loss program?