Insulin resistance inhibits sodium excretion by the kidney
Why is so much of the population hypertensive now? Why is its prevalence rising? Does the whole country actually need to be taking a blood pressure pill? The UK documented a 40 percent reduction in stroke between 2006 and 2012 via the simple public health maneuver of forcing the food companies to reduce the amount of salt allowed in processed foods. This strategy worked because the government targeted the pathology, recognizing that a primary cause was processed food, rather than just the symptom of being hypertensive (contra Modern medicine tends to target the pathology of an illness rather than preventing it).
So, is salt really the villain we make it out to be? Currently, the FDA suggests that we consume a maximum of 2.3 grams per day, and only 1.5 grams for those with hypertension. This admonishment exists despite our current median salt consumption of 6.9 grams per day, a tripling over what we actually need. Then again, our recent ancestors, prior to refrigerators, would consume over 15 grams of salt per day! In the bad old days of clipper ship fishing without engines or refrigeration, the fish would have to be salt-cured to protect them from bacterial infestation and contamination. You survived in the winter because you salt-cured your meat and fish in the spring.
So why didnāt 15 grams of salt a day cause our ancestors to stroke out routinely? The reason is because the kidney is very adept at excreting excess sodium. But thereās one thing that inhibits sodium excretion by the kidneyāinsulin resistance. High insulin levels increase blood pressure, even with relatively low sodium intake. And many people are insulin resistantāand those people do need to lower their salt as a treatment of the disease. It isnāt just the saltāitās also our processed food.
References
- Lustig, Robert. (2021). Metabolical Chapter 2. āModern Medicineā Treats Symptoms, Not Disease (p. 52). New York, NY: HarperCollins Publishers.