How can anorexia cause heart attacks ?

Not heart attacks: Anorexia can cause many problems. When you are severely malnourished then the salts in your body (sodium, potassium, chloride, calcium, etc) can become unbalanced. This can lead to life threatening heart rhythm problems like abruptly stopping (sudden death) technically this is not a heart attack which is when a portion of your heart muscle dies because of poor blood flow.

Anorexia nervosa?: Anorexia means loss of appetite. Lots of causes. Most aren't associated with heart attack. Anorexia nervosa is a speciific disease, with morbid fear of at gain, distorted body image, restricted intake/semi starvation, excessive wt loss. Leads to loss of muscle mass, including heart, vitamin/mineral/ electrolyte problems, leading to rhythm probe, heart failure, even death.