Dear Mark: Salt and Blood Pressure

The salt debate rages on outside these halls, but I’ve never really opened MDA’s doors to the tempest (beyond a short dalliance several years ago). Today, though, I am. We’ve likely all consumed a fair bit of sodium chloride over the past holiday weekend, and I imagine a few of us are wondering whether that’s a problem or not. Ever timely, reader John has written in with his salt story and a simple question: how much salt is suitable for humans? Here’s his question: I went Primal last year, and I’m down about 25 to 30 pounds and blood pressure is lowered. I have definitely followed your advice on low salt. For example, if I buy tomato sauce or paste, I get the “No Salt”, and I buy the low salt cashews, preferably with sea salt. What do you think about this new research that has come out, saying that salt is not that bad for you, and that it’s not actually related to heart disease? Just wanted your take. John There’s a lot of back and forth on salt, even among mainstream researchers. It used to be that dietary salt was absolutely evil, that it would spike your (everyone’s!) blood pressure and cause certain heart attacks and stroke. I mean, your average health-conscious grandparents probably still eat all their foods unsalted because, along with egg whites and 1% milk,  that’s just how you ate when you were trying to lower blood pressure and reduce the risk of an early death. But then stuff like the research to which John is most likely referring rolls around: this study (from the Cochrane Review in the American Journal of Hypertension) that Scientific American featured in its recent story, “It’s Time to End the War on Salt.” In fact, salt is kinda like the new egg. Will it or won’t it (kill you/clog your arteries/give you cancer/enter nefarious-sounding characteristic of necessary dietary component here)? First of all, outright demonization of an element as important as sodium is silly and foolish. We literally have a physiological requirement for sodium (about 500 mg per day), and we come equipped with sensory apparati on our tongues (taste buds) specific to salt and extant for the express purpose of identifying salty things so we can consume them. It’s obvious that salt is necessary, and that it’s not poison. In fact, it: Supports the nervous system – both sodium and chloride (also known as sodium chloride, or salt) are necessary for the firing of neurons. Regulates blood pressure – keeps it from going too low or (usually) too high. Helps maintain acid-base balance and blood volume. Supports the function of the adrenal glands which produce dozens of vital hormones, including the stress and sex hormones. But how much is too much? Is there such a thing as a limit to sodium intake? Loren Cordain thinks the amount of salt average Americans get daily – almost 10 grams, or 3,875 mg of sodium – is excessive and evolutionarily discordant as indicated by the … Continue reading Dear Mark: Salt and Blood Pressure