53. Histamine Intolerance vs MCAS: How To Tell The Difference

Many people with flushing, hives, anxiety, brain fog, digestive issues, food sensitivities, and heart palpitations are told they have either histamine intolerance or Mast Cell Activation Syndrome (MCAS). While these conditions can look remarkably similar, they have very different underlying mechanisms—and understanding those differences is often the key to finding the right treatment.In this episode, Joanne explains the difference between histamine intolerance and MCAS, why symptoms overlap, and why some people continue to react despite following a low histamine diet. Drawing on her clinical experience, Joanne explores how histamine is processed in the body, the role of DAO and HNMT enzymes, common triggers for mast cell activation, and why addressing the root cause is essential for long-term recovery.She also discusses the connection between mould mycotoxins, gut dysfunction, SIBO, oxalates, nervous system dysregulation, and histamine-related illness, while sharing practical insights into how she approaches assessment and treatment in clinical practice.In this episode, you'll learn:The difference between histamine intolerance and Mast Cell Activation Syndrome (MCAS)Why these conditions share many of the same symptoms but require different treatment approachesHow DAO and HNMT enzymes help regulate histamine in the bodyCommon causes of histamine intolerance, including gut dysfunction, SIBO, mould exposure, oxalates, and hormone imbalancesWhy MCAS symptoms are often more severe, unpredictable, and triggered by non-food factorsThe connection between mould mycotoxins, chronic inflammation, and mast cell activationWhich laboratory tests may be helpful—and why some commonly recommended tests have limited clinical valueJoanne's clinical approach to identifying and treating the root causes of histamine-related symptomsWhether you're navigating histamine intolerance, suspect MCAS, or you're a healthcare practitioner wanting a deeper understanding of these complex conditions, this episode provides practical, evidence-informed insights to help you take the next step towards better health.✨ Want more? Follow on Instagram, Facebook, and YouTube for updates and tips.📘 New to this journey? Buy The Ultimate Bundle for Managing Histamine Intolerance—your step-by-step guide to manage your histamine intolerance effectively. 🧪 Curious about your methylation status? Try our at-home Methylation Test! In just 15 minutes, discover if you're over-methylating or under-methylating and receive targeted supplement recommendations to help rebalance. Use code HISTAMINEWELL10 for 10% off.🎓 Practitioner or student? Join the waitlist for the Histamine & Methylation Online Group Coaching Course starting early 2026!📆 Work with us 1:1! Book a consultation and take your first step to real healing.🎤 Have a topic suggestion? Submit it here!