"the kidney is very adept at excreting excess sodium. But there’s one thing that inhibits sodium excretion by the kidney—insulin resistance. High insulin levels increase blood pressure, even with relatively low sodium intake. And many people are insulin resistant—and those people do need to lower their salt as a treatment of the disease."
Correct, for most people. The book I quoted is by Dr Robert Lustig who is a leading voice on that point of view. He would more or less say insulin resistance is the root problem. Chronic conditions like hypertension are symptoms. The whole book is an argument in favor of curing the underlying metabolic disease with diet adjustment.
Cutting out sugar and carbohydrates is key. Recommending lowering salt intake is a low priority when the root cause is usually insulin resistance/obesity.
"the kidney is very adept at excreting excess sodium. But there’s one thing that inhibits sodium excretion by the kidney—insulin resistance. High insulin levels increase blood pressure, even with relatively low sodium intake. And many people are insulin resistant—and those people do need to lower their salt as a treatment of the disease."