Meet the team
behind Lutanen Health

Each member of our practice brings deep clinical expertise, a commitment to personalized medicine, and a shared vision for reimagining what healthcare can be.

Four medical professionals, three women and one man, sit and stand around a modern tan sofa in an office. Two have stethoscopes, and all are smiling—an approachable concierge medicine team in business or business-casual attire.

We’ve intentionally built a small, highly collaborative team to ensure every patient receives thoughtful, individualized attention. From our physicians to our health coaches and operational staff, every person at Lutanen plays a vital role in supporting your health journey. Today and for the long run.

Advanced Diagnostics & Biometrics

Personalized for Performance

Resilience by Design

Holistic approach

Preventive by Nature

Built for Longevity

Our
team

We are proud to introduce the people who bring the vision of Lutanen Health to life. While titles and credentials matter, what truly sets this team apart is their passion for building meaningful relationships and providing care that is both data-driven and deeply human.

Each team member is hand-selected not only for their expertise, but for their alignment with our values: precision, empathy, collaboration, and continuous innovation.

A smiling man with glasses and a beard, part of a concierge medicine team, wears a plaid blazer, blue shirt, and stethoscope draped around his neck, standing in front of a leafy green background.

Jay Luthar, MD

Founder and Medical Director
Instructor in Medicine, Part-time at Harvard Medical School

Meet Dr. Luthar

A woman with long light brown hair smiles confidently with her arms crossed. She is wearing a white blazer and dark pants, representing the concierge medicine team in front of a blurred green foliage background.

Sara Rantanen

Director of Operations Co-Founder

A woman with light brown hair in a low bun is smiling, standing with one arm crossed and the other hand touching her chin. She is wearing a beige lace top and earrings, with a green leafy background like a concierge medicine team portrait.

Julia Loewenthal MD

Internal Medicine Primary Care
Geriatrician, Director Housecalls Program
Assistant Professor, Harvard Medical School

Meet Dr. Loewenthal

A woman with long dark hair, wearing a short-sleeved dark brown top and white skirt, smiles while standing in front of a leafy green background, representing the friendly concierge medicine team.

Rachel Grosklags RN

Lead RN

Meet Rachel

At Lutanen Health, we believe exceptional care begins with an exceptional team

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Our Mission

Our
mission

At Lutanen Health, our mission is to create a transformative primary care experience that empowers patients to thrive across every dimension of health.

We care about the human not the condition.

Our practice is guided by four core commitments

Precision

We rely on the most advanced diagnostic tools and clinical data to inform every decision.

Presence

We take the time to listen, understand, and build deep relationships with our patients.

Proactivity

We believe in catching issues before they begin and optimizing health, not just managing disease.

Partnership

We walk alongside you, collaborating on a tailored health strategy that evolves with your needs.

The minds and hearts behind your wellbeing

Our doctors are on faculty at Harvard Medical School and on staff at Brigham Women’s Hospital, giving our patients seamless connectivity into the Mass General Brigham network.

Two smiling healthcare professionals, a woman and a man, both wearing stethoscopes around their necks, stand side by side against a dark background, representing a dedicated concierge medicine team.

Careers at Lutanen

We are always looking for mission-aligned professionals who want to do meaningful work in a collaborative, forward-thinking environment.

At Lutanen Health, we offer more than a job. We offer a place to grow, innovate, and be part of a team that’s raising the standard of care. Whether you’re a clinician, coach, or operations specialist, you’ll make a meaningful impact on patients’ lives and help shape the future of medicine.

If you’re passionate about longevity science, precision care, and holistic healing, we’d love to hear from you.