The gut–heart connection
The heart and the gut grew up wired together, and they still talk constantly. That is why gut hormones move blood pressure, and why a big meal can drop it. It is also why a “gut” symptom can be a heart one, and the reverse.
Go deeper
2 layers below. Open any one.The gut’s blood supply is called the splanchnic circulation. It holds a huge, adjustable reservoir the body shifts on demand. Gut hormones act on the heart and vessels, not only on digestion. They include GLP-1, serotonin, VIP and PYY. GLP-1 is glucagon-like peptide-1. VIP is vasoactive intestinal peptide. PYY is peptide YY. The portal system ties the two together mechanically.
After a meal, blood pooling in the gut can drop blood pressure enough to cause dizziness or falls. This is a real, missed cause in older people. And the gut’s hormones are why a diabetes drug class, the GLP-1 agonists, turned out to protect the heart. GLP-1 stands for glucagon-like peptide-1, a gut hormone. Drugs acting like this hormone are sold under various brand names. That is a modern proof the two systems are one. See the gut as one system.
Questions to bring
Copy these, or read them out. They fit in a short visit.
- Could this be the gut–heart axis rather than one organ — for instance dizziness after meals?
- Do my gut and heart medicines interact through it?
The short version
- Getting ahead of it
- Treat the person as one system — bring gut and heart symptoms to the same clinician.
- Your testing regime
- Check lying/standing and after-meal blood pressure when dizziness follows meals; review gut and heart medicines together.
- What they don’t tell you
- A meal can drop blood pressure enough to cause falls, and gut hormones move the heart (why GLP-1 drugs help it).
- What it can spawn
- Falls and faints from post-meal pressure drops, and missed diagnoses when each organ is read alone.
- What it’s confused with
- “Just dizziness,” and a purely cardiac or purely GI label for a shared-axis problem.
From general physiology and cardiology; not a diagnosis; nothing here comes from any individual’s medical record.