LifeWeigh Weight Loss Staff

Our weight loss staff practices a comprehensive holistic team approach with multi-disciplinary medical caregivers who participate in the diagnosis and ongoing treatment of overweight patients. Our Mission is to assist each patient in achieving their weight loss and health objectives through comprehensive surgical care and education of unmatched quality and value.

Our Bariatric Surgeons

Jeffrey Rosen MD FACS MBA

Medical Director of Surgery at
Advocate Good Samaritan Hospital

Dr Jeffrey Rosen has been working in the field of bariatrics for over 20 years. He is board-certified in general surgery and has been in practice for over 25 years, including Trauma surgery, robotic bariatric surgery and general surgery. Dr. Rosen has taught Bariatric surgery to many surgeons around the country. He has been involved in thousands of weight loss surgeries. His theory of “Three Cogwheels of Wellness” has been fully integrated into the LifeWeigh practice. Long term wellness and weight loss are the cornerstone of his practice beliefs.

He has also served many administrative roles including Bariatric Director at Advocate Good Samaritan Hospital for over 10 years as well as Co-medical director in the Trauma department at Good Samaritan Hospital in the past. His dedication to advancing knowledge of surgical techniques and technology is reflected in his active memberships in various medical associations including American Society of Metabolic and Bariatric Surgery, the Society for American Gastrointestinal Endoscopic Surgeons, and the Illinois Obesity Society. In the academic arena, Dr. Rosen is an Affiliate Clinical Instructor at the Midwestern University College of Osteopathic Medicine, and his research has been published in various medical publications, including the Journal of Trauma and Surgical Endoscopy.


Allen T. Mikhail, MD, FACS

Medical Director of Bariatrics at
Advocate Good Samaritan Hospital

Dr. Allen Mikhail is a board certified bariatric surgeon at LifeWeigh Bariatrics and Wellness Centers for over 10 years. He has performed thousands of weight loss procedures and prides himself on the total care of the patient. He is trained from the world-renowned Cleveland Clinic in the newest and most advanced techniques in Advanced Laparoscopic, Endoscopic and Bariatric Surgery. Currently Dr. Mikhail uses that knowledge to offer patients at LifeWeigh the whole spectrum of care at all levels of health. Dr. Mikhail has been involved with teaching surgeons on how to perform and care for bariatric surgery patients and reflux patients. He is also a respected member of the hospital medical staff serving on several select leadership committees. He has been the investigator on many research grants and has published numerous papers, abstracts and book chapters related to nutrition, laparoscopic gastrointestinal surgery and bariatric surgery.

Articles by Dr. Mikhail


The Bariatric Team

Karli Burridge, PA-C, MMS, FOMA

Director of Medical Weight Management

Karli Burridge is a board-certified Physician Assistant, specializing in Obesity Medicine. She is comprehensively trained in medical obesity treatment, as well as in bariatric surgery. She is passionate about helping patients achieve their health goals using science-based interventions, in a comfortable and compassionate environment.

Karli completed her undergraduate studies in Psychology and Physiology at the University of Arizona and went on to study Clinical Exercise Physiology at the University of Texas. She completed her Masters of Medical Science in Physician Assistant studies at Midwestern University in 2009. She has experience working in Family Medicine, Bariatric and General Surgery, and in non-surgical, medical obesity management. She earned her Certificate of Advanced Education in Obesity Medicine in 2017.

Karli is very involved in national initiatives to improve obesity care, and to further obesity medicine education for other clinicians. She has served as a Subject Matter Expert on obesity for numerous organizations. She is immediate past Chairperson for the PA/NP Committee for the Obesity Medicine Association, and president of the PA Special Interest Group in Obesity Medicine. She has received multiple awards for her work through the Obesity Medicine Association.

She is a nationally recognized speaker and faculty member and continues to present at several of the largest health care meetings in the country on the topic of the disease of obesity.


Certified Nurse Practitioner: Karyn L. Skleney, MSN, APN, NP-C is a nurse practitioner who has worked in the field of bariatrics/general surgery for over 30 years.  She is a graduate of Elmhurst College where she received a Bachelor of Arts in Psychology and subsequently a Bachelor of Science Degree in Nursing.  She completed her Master’s degree in Nursing at North Park University and is a Certified Nurse Practitioner.  She is a member of the American Society for Metabolic and Bariatric Surgery (ASMBS). 

Practice Manager: Gail R. Rosen, RN, MSN/MBA the practice manager for over 10 years and has extensive clinical experience in the Intensive Care Unit.  Gail has received a Master’s of Science in Nursing and a Master’s in Business Administration from the University of St Francis. 

Office Manager: PJ Stough has been with LifeWeigh team for over 10 years and has served bariatric patients for over 20 years. PJ had gastric bypass surgery on July 21, 1999, and lost 162 pounds. Inspired by the way surgery changed and saved her life, she began working with bariatric patients since 2002. She has worked as a Bariatric Coordinator where she worked with patients, conducted informational seminars and ran support groups. She is a Certified Support Group Leader and a member of the American Society for Metabolic and Bariatric Surgery (ASMBS) and the Obesity Action Coalition (OAC). She has also served as the Chairperson for the Northern Illinois Walk from Obesity for over 5 years.

Dietitian: Dana Petersen White, MS, RDN, LDN is a registered and licensed dietitian working at LifeWeigh for over 10 years who has a passion for nutrition, exercise, and people. She has clinical experience in weight management and bariatric surgery. She enjoys giving presentations and developing new ways to make nutrition easy to understand and implement. Dana graduated from Purdue University and completed her dietetic internship at the University of Houston and her Masters Degree in Nutrition and Wellness at Benedictine University. She has also attained a certificate of training in Adult Weight Management through the Academy of Nutrition and Dietetics.

Dietitian: Adrienne Dink MS, RDN, LDN is a registered and licensed dietitian. Adrienne graduated with a B.A. in Psychology from St. Mary’s College of Maryland and then moved to Chicago to obtain her Master’s in Nutrition and Dietetics at the University of Illinois at Chicago. She enjoys working with individuals to meet their nutrition goals in a manner that is tailored to their specific needs and lifestyle. She believes that small changes to one’s eating habits overtime can lead to long lasting lifestyle changes that have a major impact on one’s health and well being.

Dietitian: Lisa Dempsey, MS, RDN, LDN is a registered and licensed dietitian who graduated from the University of Iowa with a bachelor’s degree in psychology. She completed her dietetic internship and master’s degree in the Coordinated Program in Nutrition at the University of Illinois at Chicago. Lisa has clinical experience in outpatient weight management and bariatric surgery as well as inpatient critical care. She is a member of the Academy of Nutrition and Dietetics and the Weight Management Dietetic Practice Group. Lisa is passionate about helping individuals improve their health through nutrition. 

Exercise Physiologist: Joey Bonavota, MS has been working in the field of bariatrics since 2002. He is an alumnus of Eastern Illinois University, where he received both his Bachelor and Masters degree in the field of exercise science. He has also gained practical experience in the field of cardiac rehabilitation. Joey brings a unique perspective into the field of exercise science through his previous endeavors. 

Exercise Physiologist: Marty Trejo, MS, CES received his masters degree in exercises science with a discipline of human movement science, and sports nutrition spring of 2019 from Concordia University Chicago where he also received his bachelor’s degree in exercises science. Prior to working in the field of bariatrics he gained practical experience at Rush medical center in Chicago in the exercise physiology department. 

Social Worker: Janet Zimmerman, MSW, joined LifeWeigh in 2013. She earned her Masters in Social Work from Loyola in 1992. At LifeWeigh, Janet offers confidential counseling to aid our pre and post-surgical patient in their weight loss journey. When not counseling our patients, Janet can be found at the front desk getting our patients ready for surgery.

Front Desk Reception: Brandee Giovenco, AAS earned her associate degree in Applied Science from William Rainey Harper College. She previously worked in the Advocate health care system – where she worked in both the PreSurgical and Emergency departments. She is always friendly and on the lookout for better ways to assist and communicate with patients, Brandee is currently learning American Sign Language.

Contact us to schedule your consultation and meet our weight loss team.

Let Us Help You Reach Your Weight Loss Goals

Register For A Weight Loss Seminar To Take The First Step Towards
A Healthier and Happier You