Also by not trying to lose weight primarily through physical activity. Someone who has been morbidly obese for a very long time has basically placed their organs (and joints and tendons)under seige for an extended period. It's not like you can suddenly take that type of person's heart and suddenly subject it to strenuous exercise without increased risk of problems.

Weight loss happens in the kitchen not the gym.

If I understand right, the odds are still better for folks who are more active - it's just tragic lousy luck, if it's what happened.

Lose it slowly. 1-3 lbs a week. Listen to your body. Probably have a doctor that can do some blood work to help get your cholesterol levels under control before you go too crazy into it.