Can't loose weight too fast?

Dear Ask The Doctor: A very obese friend of mine was told that something in her blood work told a doctor that she shouldn't loose weight too fast. I am curious to what kinds of things would cause that doctor to be cautious.

Dear Rachel: Generally speaking, slow steady weight loss is always healthier than rapid weight loss and I agree with your friends doctors suggestion.  Slow steady weight loss is often an indication of a healthy lifestyle change as opposed to extreme dietary restrictions or unsustainable exercise regimes that will result in putting the weight back on once stopped.

Specific medical conditions need to be monitored more frequently during weight loss to prevent adverse events from taking place. Such medical conditions include asthma, cystic fibrosis, diabetes, hypertension, renal disease, thyroid disorder, cancers involving chemotherapy treatment and anemia's.  I am not sure which one applies to your friend.