Ehlers-Danlos Syndrome (EDS), Postural Orthostatic Tachycardia Syndrome (POTS), and Mast Cell Activation Syndrome (MCAS) often overlap, though not always. Each condition can independently—and collectively—interfere with a person’s ability to meet nutritional needs. Despite how frequently this is observed in clinical practice, the relationship between these conditions and malnutrition remains poorly defined in the literature.

EDS is a group of inherited connective tissue disorders affecting collagen structure and function. Individuals commonly experience gastrointestinal symptoms such as dysmotility, functional dyspepsia, gastroparesis, pelvic floor dysfunction, structural abnormalities and chronic abdominal pain—factors that can significantly limit food intake and tolerance.

POTS is a disorder of the autonomic nervous system that can disrupt digestion, gastrointestinal motility, and fluid balance. Symptoms such as early satiety, nausea, bloating, constipation or diarrhea, and worsening orthostatic symptoms after meals often lead to reduced intake or skipped meals.

MCAS involves inappropriate mast cell activation and mediator release, including histamine. When mast cells in the gastrointestinal tract are involved, symptoms may include food sensitivities, reflux, malabsorption, loose stools, urgency, nausea, and vomiting. These symptoms frequently result in highly restrictive eating patterns.

While these symptoms are often addressed individually, together they represent multiple pathways to inadequate nutrition. Further complicating care is the wide spectrum of symptom severity and variability in how patients present. Dizziness, brain fog and fatigue are common symptoms, likely intensified by inadequate intake. Gastrointestinal dysfunction, unpredictable food reactions, and post-meal symptom flares can interfere with intake and absorption while also contributing to food-related anxiety and avoidance. Studies suggest that over 60% of patients engage in food restriction or routinely skip meals, further increasing nutrition risk. However, it remains unclear whether malnutrition in this population is driven primarily by inadequate intake, malabsorption, or both.

Despite the clear clinical need, research exploring the mechanisms, prevalence, and optimal nutrition interventions for patients with EDS, POTS, and MCAS is limited. This lack of data directly affects clinical care and leaves many questions unanswered, leaving both patients and healthcare providers frustrated.

More research in this area has the potential to inform targeted, evidence-based nutrition strategies that better support these patients. While nutrition is not a cure for EDS, POTS, or MCAS, it plays a foundational role in supporting physiologic stability, symptom tolerance, and overall quality of life. When thoughtfully applied, nutrition can be a powerful tool.

This is an underserved population that I’m incredibly passionate about. Fellow healthcare professionals, think of this post as a live-brain storming session.

Thanks for reading!

Publications to review: PMID: 40387691, PMID: 39268060, PMID: 31476322, PMID: 37970870