Newbie

I am just starting my bariatric journey. I have been overweight my whole life and have spent years on the yoyo diets. No at the age of 41 I feel like if I don't do something about this weight now then I'm going to end up not being able to walk and having to rely on someone else for the rest of y life. I had my first appointment with the dietitian to get the process started. My insurance requires a 9 month waiting period in which I have to show that I am serious about losing the weight. However my weight can't drop below 300 lbs. because that will drop my BMI too low for the surgery. I've been trying to cut back on the carbs but I think I a, little confused as to how that works. I thought you subtract the total amount of protein from the Carbs to get your true carb total. I also just watched a video of the surgery and I am a bit freaked out. I guess I am a bit overwhelmed.