K. A.

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Hands down the best surgeon on earth. Dr Lyass performed my sleeve gastrectomy. My surgery was at brand surgical (most amazing staff I have ever seen!!!!!!!!) Dr Lyass has answered any and every question I ever had. I have already lost FIFTY pounds! His technique is amazing and honestly I had absolute minimal pain. ⭐⭐⭐⭐⭐

A. K.

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I am so happy I had the opportunity to know and meet Dr.Lyass, very professional, he knows what his doing . Staff very helpful, nice environment friendly helping as much as possible, love it thankful for each of one. ⭐⭐⭐⭐⭐

A. G.

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Dr. Lyass literally changed my life. Went from 280 to 180 pounds in 3 years. 100 pounds of fat gone. He is extremely knowledgeable in Bariatric procedures and his bedside manner is impeccable. Highly recommended! ⭐⭐⭐⭐⭐

G. J. - Los Angeles, CA

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Dr. Lyass is a really nice doctor who really cares about his patients. If your looking for a really good weight loss surgeon, Dr. Lyass is the best. ⭐⭐⭐


Sergey Lyass, MD

Bariatric Surgeon and Weight Loss Physician serving the Los Angeles area

Sergey Lyass, MD is a bariatric surgeon, weight loss specialist, and da Vinci® robotic surgery provider serving patients in Los Angeles, Glendale, and Marina del Rey, California. He received his medical degree from the 2nd Moscow Medical Institute (now Moscow Medical University) in 1985.

He was trained in general surgery in Israel at the Hebrew University-Hadassah Medical Center in Jerusalem, and did his internship at Mount Sinai Medical Center in New York City. Dr. Lyass completed both his surgical residency and his fellowship in minimally-invasive and bariatric surgery at Cedars-Sinai Medical Center in Los Angeles.

Dr. Lyass is board certified in general surgery. He has more than 25 years of experience performing surgery, including various types of minimally-invasive procedures and bariatric weight-loss surgeries using the da Vinci Surgical System.

Dr. Lyass is the author of more than 100 scientific publications and book chapters in leading medical journals. He is fluent in Russian and Hebrew.

Professional Education:

  • Internship: Mount Sinai Medical Center, New York, NY
  • Residency: Cedars Sinai Medical Center, Los Angeles, CA
  • Fellowship in Minimally Invasive and Bariatric Surgery: Cedars Sinai Medical Center, Los Angeles, CA.
  • 2006 – Board Certified in General Surgery