Dr. Jay Luthar and Dr. Julia Loewenthal have been named 2026 Castle Connolly Top Doctors, marking the second consecutive year they have received this designation. Only 7 percent of the nation's licensed physicians are selected annually for this recognition based on peer nominations and rigorous review by Castle Connolly's physician-led research team. The selection process evaluates medical education, training, hospital appointments, and disciplinary histories, with doctors prohibited from paying for inclusion.
Both physicians practice at Lutanen Health, a primary care and longevity practice in Boston's Back Bay that limits each doctor to 150 patients, contrasting with traditional volume-driven models. The practice integrates longevity science into everyday care, making it the only academically affiliated primary care practice in Boston with this focus. "The Castle Connolly recognition affirms what I believe matters most in medicine: time, trust, and partnership," said Dr. Luthar, emphasizing their shared conviction that care should be uniquely designed for each individual patient.
At Lutanen Health, primary care transforms into private health management that identifies risks before symptoms emerge and allocates interventions across a lifespan to preserve vigor and delay decline. The practice evaluates and treats primary conditions with particular focus on metabolic health, cardiovascular risk reduction, cognitive preservation, and healthy aging. Their clinical team specializes in managing complex internal medicine cases while addressing unique needs of older patients, including frailty risk, medication optimization, and age-related vitality.
The practice incorporates advanced diagnostic technologies including AI-guided plaque detection, multi-cancer early detection blood testing, VO₂ max testing, biological age tracking, advanced biomarker and genetic analysis, comprehensive fitness and mobility assessment, and structured sleep evaluation. Their newly designed 3,000 square foot facility includes a state-of-the-art human performance laboratory and offers amenities reflecting their relationship-driven model: extended visits, same-day appointments, 24/7 physician access, individualized nutrition counseling, and select home visits.
Both physicians bring specialized training to their practice. Dr. Luthar completed his medical residency at Cambridge Hospital, a Harvard Internal Medicine Residency Site, and is board-certified in Internal Medicine, Integrative Medicine, and Lifestyle Medicine. Dr. Loewenthal completed her Internal Medicine residency at Brigham and Women's Hospital and her fellowship in Geriatric Medicine through the Harvard Multi-Campus Geriatrics Program. She is board-certified in both Internal Medicine and Geriatric Medicine, and board eligible in Integrative Medicine.
Maintaining academic faculty roles at Harvard Medical School, where Dr. Luthar serves as an Instructor and Dr. Loewenthal serves as an Assistant Professor, their work bridges clinical care, education, and research to advance the science of healthy aging. Their recognition as Top Doctors highlights a growing movement toward preventive, relationship-based medicine that prioritizes long-term health outcomes over reactive treatment. Castle Connolly publishes its Top Doctors list at https://www.castleconnolly.com and in various print and online partner publications.
