Friends, can we talk about that salt study?
Maybe you've heard of it, maybe you haven't, but in the kinds of places I like to hang out the internet has been all up in a twitch over an article published in the New York Times earlier this month titled Why Everything We Know About Salt May Be Wrong. The article outlines a recent study on Russian cosmonauts, held in isolation to simulate space travel, which challenges conventional nutrition wisdom when it comes to salt consumption. For years we've been told that salt makes us thirsty, makes us retain water, and is related to increased blood pressure. What happened with these cosmonauts, though, is that increased salt consumption somehow made them less thirsty but more hungry. These findings, plus some surprisingly patterned hormone fluctuations in their urine, lead researchers to conduct further studies on mice with unexpected results: they burned more calories when they got more salt. In fact, the mice that were given a high-salt diet needed to consume an average of 25% more calories just to maintain their weight.
So here's the sensationalist nutrition headline that's making me cringe: one of the many implications of this finding is that salt may be involved in weight loss. For many years the scientific community has assumed that a high-salt diet leads to a greater intake and retention of fluids, which increases weight. This new research is suggesting that not only may that not be true, but in fact, a higher salt intake may require the body to break down tissue, thereby increasing energy expenditure and resulting in potential weight loss.
Ok, great. But before we all go wielding the salt shaker in the name of health, let's just hold our horses for a minute. May I remind you for a moment about the fat-phobic 90's? A nutritionally-confused time when fat was a killer but it was totally cool to eat an entire package of Snackwells since they were fat-free? And then, what, 15 years later the scientific community was like, shit, we made a mistake. Now fat is back - I mean people are literally putting butter into their coffee - and folks are freaking the eff out about sugar.
And now it looks like salt is getting its turn. Hey, we were wrong about salt, it's not so bad after all. Salt helps you lose weight! Salt for everyone! Whee!!!
But here is, I think, the most important statement made about this study: “The work suggests that we really do not understand the effect of sodium chloride on the body.”
One more time for the cheap seats in the back: The work suggests that we really do not understand the effect of sodium chloride on the body.
This is the thing about nutrition: it's a science that's really still in its infancy. There is so much we don't yet know. There's a lot of confusion and disagreement about nutrition within the scientific community, nevermind the minefield that is internet-based nutrition knowledge for the lay person. And yet, if you look past the wildly swinging nutrition paradigms, past the fat phobia, past the sugar phobia, past the gluten/carb/wheat phobia, you'll find some solid, consistent, universal truths. Eating a largely plant-based diet has always been good for us. Moderation has a solid track record. And beans, well, they make you toot.
Maybe we don't deeply understand the effect of salt on the body just yet. Maybe it *does* have an impact on metabolism. But experience has taught us that the nutrition paradigm will likely swing again at some point not too far down the road. So let's just try to be sensible about this, and take this study with a grain of salt (<-- see what I did there?)
Sound good?
Salt image from Shutterstock
kellie@foodtoglow
Great article, Katie. Weirdly or maybe not, I had a hunch in the 80s that the hall pass that sugar received when fat was in detention was wrong. I wasn't quite smart enough to question the evidence about fat but I really didn't go for the Snackwells and low-fat muffins option. I think instinct tells both of us that we should be very cautious about going against the perceived wisdom on salt, and yes that boring message of moderation is most likely true in this instance. But gosh I do love salt so I would be quite happy if we do find that a little more (for us salt-avoiders) might be better
Katie Trant
I also love salt, and I don't really bother avoiding it. But I don't eat out often and don't eat a lot of processed food, so my diet is naturally quite low in added salt. It would be nice to find out that a bit more is ok, but I'm sure we'll find that as with all things, moderation is the key.
Amy
Very interesting. I haven't heard anything about the salt study. Thank you for the balanced look at the issue.
Katie Trant
I'm all about a balanced approach to nutrition. Glad you enjoyed it!
Heather
Thanks for a balanced look at the salt thing and on nutritional trends in general. An excellent read!
Katie Trant
Thank you. Glad you enjoyed!
Molly
Don't usually comment, but AMEN! to this post! Extremes are never a good thing. It would be so much better for the general public if nutrition science wasn't so sensationalized.
Katie Trant
I know, right? There should be a code of ethics on nutrition reporting. And the NYT is usually pretty solid, but I get that headlines sell and headlines about magic tricks that help with weight loss sell even more. But this needs some serious explanation for the average eater who may be inclined to get the salt shaker going in the name of health!