If your body has too much insulin for a long time, it can make your kidneys hold onto more salt, which increases your blood volume and raises your blood pressure—even if you're not eating too much salt.
Evidence from Studies
Supporting (2)
Community contributions welcome
Renal tubule insulin receptor modestly promotes elevated blood pressure and markedly stimulates glucose reabsorption.
The study shows that when the kidney's response to insulin is blocked, blood pressure doesn't rise as much, especially with other hormonal stressors. This supports the idea that too much insulin can make the kidneys hold onto salt and raise blood pressure.
The study shows that turning off insulin's signal in kidney tubes reduces salt retention, which supports the idea that too much insulin can cause the kidneys to hold onto salt and raise blood pressure.
Contradicting (2)
Community contributions welcome
Chronic hyperinsulinemia and blood pressure regulation.
The study raised insulin levels for weeks in dogs and watched their blood pressure and salt balance. Even with high insulin, their blood pressure didn’t go up, which goes against the idea that high insulin directly causes high blood pressure.
Role of Hyperinsulinemia and Insulin Resistance in Hypertension: Metabolic Syndrome Revisited.
The study looked at what happens when insulin levels stay high for a long time, and found that it doesn’t actually lead to lasting high blood pressure, even though it might briefly affect sodium and blood pressure.
Gold Standard Evidence Needed
According to GRADE and EBM methodology, here is what ideal scientific evidence would look like to definitively prove or disprove this specific claim, ordered from strongest to weakest evidence.