Eating disorders can have many bad effects on the heart, including sudden cardiac death, heart failure and heart rhythm problems. You need to fess up to your doctor or cardiologist about your eating disorder and get checked out. A banana is not going to do it. Most importantly, get treatment for your eating disorder before something bad happens. I know, I was there. I was 17, 5'9" tall and weighed 96lbs. I still have the mind of an anorexic (if that makes any sense) but I make myself eat and maintain a normal weight. It is not easy, but if you want to live, you have to do it. Please talk to your doctor and get a referral to a therapist who specializes in eating disorders. It is the only way to stop.