Hello Quantum,
You have found a good place for LC and General health information, their are a number of sub-forums including one on cholesterol and heart disease. http://forum.lowcarber.org/forumdisplay.php?f=48
Congratulations, you are already at a healthy BMI of 23. You may want to work on strength or other NSV rather than a goal that is underweight, especially if recovering from surgery. All the best,