Medical Weight Loss
in Port Jefferson, NY
Personalized, doctor-supervised weight loss programs designed to help you feel better, move better, and live better—
right here in Port Jefferson, NY.
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About Our Office
Helping Port Jefferson
Feel Their Best
One Patient at a Time
At Long Island Weight Loss Institute, we provide real solutions—not fad diets. Our Port Jefferson location offers comprehensive, medically guided weight loss programs designed around your body’s unique needs. Whether you're managing a slow metabolism, hormonal imbalance, or just haven't found the right plan, we’re here to help.
Our team includes licensed medical professionals who guide you every step of the way with expert care, science-backed treatment plans, and ongoing support.
Doctor-Supervised Programs
InBody Composition Scanning
Supportive, Judgment-Free Office
Custom Nutrition & Medication Options
Convenient Port Jefferson Location
Our Team
Meet Your Local Care Team
Our Port Jeff providers bring warmth, experience, and compassion to every patient interaction. When you visit our office, you’ll work with a team that truly listens, educates, and customizes a plan that works for you.
Dr. Michael S. Kaplan, DO, ABOM
Obesity Medicine/Internal Medicine
Dr. Michael Kaplan has been a founding partner of the Long Island Weight Loss Institute (LIWLI) and the center for medical weight loss (CMWL). In September 2014 Dr. Kaplan resigned as the Chief Medical Officer of CMWL.
Secondary to philosophical differences with CMWL management on the importance of being a practicing physician Kaplan ended his affiliation with the CMWL programs to focus on providing outstanding medical care through the Long Island Weight Loss Institute. Kaplan developed the CMWL weight loss program and wrote the patient counseling materials that are used in CMWL offices.
Our Process
What to Expect at Your First Visit
1. Consultation
Meet with our provider to review your goals, health history, and concerns.
2. inbody scan
A quick, non-invasive body composition analysis.
3. CUSTOMIZED PLAN
We’ll walk you through treatment options that work for you, whether that’s nutrition guidance, GLP-1 support, or ongoing monitoring.
4. ONGOING SUPPORT
Weekly or bi-weekly check-ins, progress tracking, and long-term strategies.
Real Patients. Real Results.
We’ve helped thousands across Long Island lose weight, reverse symptoms, and take back control of their health. Here are just a few success stories from patients in and around Port Jeff:
Hover over the images to see the Before
Carmela B.
Lost 33* pounds
*individual results may vary
“I would have to say the best part about losing weight has been self-confidence; it comes into play with everything you do, at least for me. Also, going into a store after having gone from a size 12 to a size 4 to 6!”
Donna D.
Lost 44.5* pounds
*individual results may vary
“This way was by far the easiest and most effective diet I’ve ever done. Each week, I receive the guidance and knowledge necessary for me to make appropriate choices. And talk about choices!”
Mark N.
Lost 93* pounds
*individual results may vary
“My blood pressure is down, my cholesterol is down, my weight is down - and my self-esteem is way up. I really feel this ultimate change in my life would have been impossible without the help and guidance from the LIWLI team”
Frequently
Asked Questions
Do I need insurance to book a consultation?
No insurance is needed for your free consult. We’ll walk you through all available options.
What medications do you offer?
We offer a range of GLP-1 medications, appetite suppressants, and supplements—prescribed only when appropriate for your body and goals.
What makes LIWLI different?
Our program is medically guided, fully customized, and designed for long-term results—not quick fixes.
Ready to Start Your Journey?
We’re Right Here in Port Jefferson
Let’s get your consultation on the calendar. Fill out the form and a member of our team will call you to confirm your appointment.
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Hours
Monday–Friday: 9:00 AM – 5:00 PM
Saturday: By appointment
