Advance Health Integrative and Functional Medicine is a physician-led functional medicine practice in West Los Angeles, founded and directed by Dr. Rashel J. Tahzib — one of the few physicians in the country who is both a board-certified osteopathic family physician and a Certified Practitioner through the Institute for Functional Medicine (IFMCP). Dr. Rashel's approach is built on the conviction that most chronic illness has identifiable, upstream root causes — and that genuine healing requires finding them rather than managing symptoms indefinitely. The practice serves patients throughout Los Angeles who are struggling with complex, chronic, or unexplained conditions: people who have seen multiple physicians, received confusing or conflicting diagnoses, and still feel unheard. Dr. Rashel employs advanced functional diagnostics — including comprehensive hormone panels, microbiome analysis, genetic SNP testing, neurotransmitter profiles, and heavy metal testing — to build a precise, individualized picture of each patient's biology, and then treats the actual causes of dysfunction rather than simply suppressing symptoms.

About the Physician

Dr. Rashel J. Tahzib, DO, AOBFP, IFMCP, is a board-certified physician through the American Osteopathic Board of Family Physicians with 25+ years of clinical experience, including over 20 years practicing functional, integrative, and anti-aging medicine in Los Angeles. She is one of the few physicians in the US to hold certification from the Institute for Functional Medicine — a rigorous credentialing process that qualifies her to practice systems biology and upstream medicine at its most advanced level. Dr. Rashel is also affiliated with the American College for Advancement in Medicine (ACAM) and the American Academy of Anti-Aging Medicine (A4M/MMI). Her personal journey with an autoimmune condition deepened her commitment to functional medicine and drives her empathy for patients who are suffering from conditions that conventional medicine has failed to resolve. She practices at the West LA location and also serves patients in Greenwood Village, Colorado, with mobile and virtual visits available throughout California and Colorado.

Services Offered

• Functional Medicine Consultations — Comprehensive root-cause evaluations using advanced functional diagnostics, systems biology, and upstream medicine — designed for patients with complex, chronic, or unresolved conditions that conventional medicine has not adequately addressed.
• Bioidentical Hormone Therapy (BHRT) — Customized, evidence-based BHRT for men and women — addressing testosterone, estrogen, progesterone, DHEA, thyroid, and adrenal hormones based on comprehensive hormone and metabolite testing.
• Thyroid Health Optimization — Specialized evaluation and treatment of hypothyroidism, Hashimoto's thyroiditis, and other thyroid disorders — going beyond TSH alone to assess the full thyroid picture and identify autoimmune and nutritional contributors.
• Autoimmune Disease Reversal — Functional medicine protocols for rheumatoid arthritis, lupus, multiple sclerosis, Hashimoto's, Graves' disease, psoriasis, celiac, and inflammatory bowel disease — aimed at reducing immune activation and restoring balance.
• Gut Health Restoration (SIBO, Candida, Leaky Gut) — Comprehensive gut assessment and treatment for SIBO, candida overgrowth, intestinal permeability, IBS, Crohn's, and ulcerative colitis — using breath testing, comprehensive stool analysis, and targeted therapeutic protocols.
• Functional Medical Weight Loss — A root-cause approach that identifies hormonal imbalances, metabolic dysfunction, insulin resistance, and nutritional deficiencies driving weight gain — then builds a personalized, sustainable protocol around the actual findings.
• Chelation Therapy & Heavy Metal Detox — Physician-supervised chelation and detoxification protocols for patients with elevated heavy metal burden — tested via advanced heavy metal panels and treated with evidence-based chelation and nutritional support.
• Fertility Optimization — Functional medicine approach to fertility that addresses nutrient deficiencies, adrenal health, hormonal imbalances, autoimmune factors, and chronic infections that may be preventing conception or healthy pregnancy.
• Advanced Biomarker & Functional Lab Testing — A comprehensive diagnostic toolkit including genetic SNP testing, comprehensive hormone & metabolite panels, food sensitivity panels (208 foods), neurotransmitter analysis, organic acids, Lyme testing, and microbiome variability assessments.

What to Expect

The West Los Angeles office is at 1849 Sawtelle Blvd, Suite 610, Los Angeles, CA 90025. Hours are Monday through Friday 9:30 AM–5:00 PM. Call (310) 979-3434, email info@drrashel.com, or visit drrashel.com to take a free online health assessment and request a consultation.