Collagen Is the Wall, Not the Paint | The Angry Gut, Chapter 7

EDS and POTS · autonomic testing

EDS and POTS: Measuring What a Normal Workup Misses

With EDS and POTS, autonomic testing measures how your nervous system regulates heart rate and blood pressure when you stand, which standard gut and heart workups are not built to do. Cardiac autonomic reflex tests and heart rate variability put that regulation on a number; your physician makes any diagnosis.

Hypermobility rarely stays in the joints. When the racing heart, the fatigue and the unsettled gut all come back normal on standard tests, the regulation behind them can still be measured.

If you live with hypermobile Ehlers-Danlos syndrome or hypermobility spectrum disorder, you may already know the EDS and POTS pairing from experience: the racing heart and gray-out on standing, the fatigue, the gut that never settles, and a stack of tests that all came back normal. Respondents to one large international survey reported a mean gap of 22.1 years between their first symptoms and a name for them. In Collagen Is the Wall, Not the Paint, the video companion to The Angry Gut by Dr. Gurpreet Singh Padda, MD, MBA, MHP, and Ami Michelle Grimes, the case is made for why a collagen body is a whole-body problem. The question here is a measuring one: which parts of that picture can actually be put on a number.

Why does EDS affect more than the joints?

Collagen is not decoration. It is the footing the gut lining stands on, the framework of blood vessels, and the tissue that holds joints together. The gut is the first brain, the organ that decides what gets into the body, and its wall is built on that same collagen scaffold. When collagen is made wrong, the effects show up wherever that scaffold works.

The numbers bear that out. Pooled across studies, people with hypermobility had 4.29 times the odds of chronic gut symptoms compared with controls. The trouble does not stop at the bowel. In the same pooled data, orthostatic intolerance, feeling unwell when upright, affected 35.9%, chronic fatigue 49%, and migraine 38.2%. Postural tachycardia pooled at 21.9%, although the range around that figure ran from 5.2% to 59.1%, wide enough that nobody should quote it as a precise rate. In the survey, 71.4% reported dysautonomia, a patient-reported label rather than a tested one.

The pattern is clear even where the mechanism is not. Autonomic symptoms are common enough in this population that they deserve measurement, not a shrug.

Why do EDS and POTS tests keep coming back normal?

Most gut and heart workups are built to find structural disease that kills: a tumor, a blocked vessel, an inflamed bowel. They are good at that job. They are not built to measure how the nervous system regulates heart rate, blood pressure and sweating when you stand up, and so they return normal in person after person.

Even the gut findings run against expectation. When symptomatic patients had pressure studies of the upper intestine, bowel motility problems were actually less common in the hypermobile group, 13% against 34%. The commonest complaints were heartburn, reflux and trouble swallowing, not a sluggish bowel. A body that moves food normally but still feels awful is one more reason to look beyond the bowel.

The delay has a social cause as well as a biological one. A patient whose scans stay clean gets labeled anxious, and a system paid to find structural disease has little reason to count the rest. Meanwhile the research money for collagen products flowed toward skin and wrinkles, where the customers were, not toward the gut or the nervous system.

What can autonomic testing show in EDS and POTS?

Measura [Cardiometabolic and Autonomic Health Analysis] has no test for collagen or connective tissue, and it does not diagnose Ehlers-Danlos syndrome or POTS. What it can measure is the autonomic side of the story, the regulation that so many hypermobile patients describe but rarely see documented. Results go to your physician, who makes any diagnosis.

Autonomic nervous system testing looks at how the involuntary nervous system is regulating the body.
Cardiac autonomic reflex tests record how heart rate and blood pressure respond to standardized maneuvers, including changes in posture.
Heart rate variability measures the beat-to-beat variation that reflects autonomic balance; what that number means is its own topic.

A measured result changes the conversation. Instead of describing a racing heart that nobody saw, you arrive with a recording of how your system actually behaved.

Balance, muscle and the protein nobody counts

Lightheadedness on standing is not only unpleasant; it is a fall risk. Vestibular and balance testing measures how steady you are, which matters for anyone who grays out when they stand. More on that link is in dizziness, balance and falls.

Muscle is the other half. Bioimpedance body composition separates muscle from fat, something a scale cannot do. That matters because the best evidence for collagen supplements is in joints, not guts, and in a review of randomized trials the muscle results were inconsistent and mostly positive only when collagen was paired with exercise.

Then there is the raw material. The gut lining rebuilds itself continuously from protein you eat. When healthy volunteers were fed only by vein for 14 days, their gut lining thinned from 645 to 512 microns. An inflamed, underfed lining feeds metaflammation, the low-grade inflammation that keeps the whole system irritated. I once thought of repair like a construction site: deliver the lumber and the wall goes up. The research in malnourished children proved me wrong. Feeding is necessary, but a gut under attack does not rebuild on protein alone. Still, nothing rebuilds without it. Add up three ordinary days of protein before assuming you eat enough, and notice whether eating alone, painful teeth or a poor appetite is quietly taking it off the plate.

What to bring to your appointment

A written list of symptoms on standing: racing heart, gray-out, fainting or near-fainting.
How long symptoms have gone without a name, and which tests were already normal.
Your gut symptoms, especially reflux and trouble swallowing.
Three days of food with protein totaled.
Every medication, including any started within a year of new bowel symptoms.
A question: can my autonomic function, balance and muscle be measured, not just described?

Every study behind these figures sits in the companion deep dive for The Angry Gut. The stomach side of nutrient absorption is covered in atrophic gastritis and B12 absorption, and physicians can read the screening version for practices.

Frequently asked questions

Are EDS and POTS related?

They often travel together. In pooled data on hypermobile Ehlers-Danlos syndrome and hypermobility spectrum disorder, postural tachycardia appeared in about 21.9% of patients, though the estimate is very uncertain, and orthostatic intolerance in 35.9%. Having one does not mean you have the other, but autonomic symptoms in a hypermobile body deserve evaluation. Read about autonomic symptoms.

Can Measura diagnose POTS or Ehlers-Danlos syndrome?

No. Measura does not test collagen and does not make diagnoses. It measures autonomic regulation, heart rate variability, balance and body composition, then sends the results to your physician. Your physician decides whether those findings, along with your history and examination, support a diagnosis and what should happen next. Learn what a test result can and cannot tell you.

Why do I get dizzy when I stand up?

Standing asks the autonomic nervous system to adjust heart rate and blood vessel tone within seconds. When that regulation falls short, blood pressure to the brain can dip and you feel lightheaded. Dehydration, medications and other conditions can cause the same thing, so the pattern needs a physician’s evaluation, and repeated dizziness raises fall risk. See how dizziness relates to the risk of falling.

Does collagen powder help hypermobility?

Not in the way it is marketed. Randomized collagen trials measured skin, bone, muscle and joints, and none tested the human gut wall. Joint results were the most positive, and muscle results were mostly positive only with exercise. Collagen peptides do reach the blood, but whether they reach damaged tissue is unproven. See why body composition matters more than BMI.

Why do my gut tests keep coming back normal?

Colonoscopy, CT scans, celiac panels and stool tests look for disease that damages or kills, and in hypermobile patients they often find none. The commonest complaints, heartburn, reflux and trouble swallowing, rarely show on those tests, and motility studies found less bowel dysmotility, not more. Protein intake is rarely counted at all. Bring these questions worth asking your doctor.

What are the symptoms of EDS and POTS together?

The common picture is a racing heart and gray-out on standing, fainting or near-fainting, fatigue, and a gut that never settles, most often with heartburn, reflux and trouble swallowing. In pooled data on hypermobile patients, chronic fatigue affected 49% and migraine 38.2%, and people with hypermobility had 4.29 times the odds of chronic gut symptoms. Many also report a long stack of normal test results.

How is POTS tested in someone with EDS?

Cardiac autonomic reflex tests record how your heart rate and blood pressure respond to standardized maneuvers, including a change in posture. Heart rate variability adds a measure of autonomic balance, and balance testing measures how steady you are when graying out is part of the picture. Measura performs these measurements and sends the results to your physician, who decides with your history and examination whether they support a diagnosis.

Why does it take so long to get diagnosed with EDS?

Survey respondents reported a mean gap of 22.1 years between first symptoms and a name for them. Standard gut and heart workups are built to find structural disease such as a tumor or a blocked vessel, so they come back normal. A patient whose scans stay clean often gets labeled anxious, and a system paid to find structural disease has little reason to count the rest.

Put your autonomic symptoms on a number

Ask about autonomic, balance and body composition testing so your physician can see how your system behaves, not just how it is described.

Send a message

4477 Woodson Rd, Suite 201, St. Louis, MO 63134. Monday to Friday, 9:00 a.m. to 5:00 p.m. Please do not send symptoms, diagnoses or images through a web form — a website form is not a secure medical channel. Send your name and number and we will call you back.

References

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