The Case for Keto: Rethinking Weight Control and the Science and Practice of Low-Carb/High-Fat Eating

by Gary Taubes

As for blood pressure, insulin induces your kidneys to hold on to sodium. (Salt is sodium chloride, and the sodium is the player here.) This is one of the many things insulin does. When your insulin levels are high, your kidneys retain sodium rather than excreting it in urine. Now blood pressure will increase as your body retains water to keep the sodium concentration in your circulation constant. When the medical authorities blame hypertension and high blood pressure on eating too much salt, they’re thinking of the same mechanism—increasing the sodium concentration in the circulation leads to more water being retained and higher blood pressure—but typically simplistically. They’re putting the blame on consuming too much salt—a behavioral problem or maybe the food industry’s fault for oversalting processed food—rather than on excreting too little, which results from chronically elevated insulin levels and insulin resistance. Lowering insulin by avoiding carbohydrates and replacing them with fat reverses this sodium-retention phenomenon, and so blood pressure should drop with LCHF/ketogenic eating, as it typically does.