A 14.5 BMI in an adult woman is actually extremely dangerous- I would say probably more dangerous than a BMI of 51.5. With a body mass that low, Jade has most definitely lost significant bone and muscle mass as her body cannibalizes itself for energy. Your heart is also a muscle, and will also be auto-cannibalized by the body. When I was 16 years old with a BMI of 15.6 at a height of 5'6", I had EKG changes that indicated my heart was shrinking and starting to fail.  This show is enraging to me when I see the "super skinnies" forced to eat these huge, fatty portions. That is extremely dangerous, as it is not only physically uncomfortable and can cause extreme constipation, gastroparesis, and even bowel obstruction- it can also cause a very deadly re-feeding syndrome, where the body's electrolytes shift so rapidly it can lead to sudden cardiac arrest. When someone has had a very low oral intake for greater than 5 days, you must always start refeeding slowly with smaller portions for a couple days, along with frequent vitals & blood tests. source: cardiac nurse for 5+ years who has been in treatment for anorexia nervosa multiple times.