The truth about salt

It is tasty, addictive, and deadly.

Oct 8

Hello!

I want to wish everyone a happy festive season first. My best wishes to you and yours.

I will keep the newsletter this week short and focus on one topic. It is the subject of my column this week for Hindustan Times, which you can read here. I want to provide additional colour, links, and resources.

We can’t avoid the truth anymore…

We are eating too much salt and it is killing us. One in four Indian adults has high blood pressure. That’s over 200 million of us. Indians, on average, consume twice as much sodium than the WHO guidelines. We’ve know this for decades now.

But new research shows that salt substitutes save lives.

Two recent landmark studies from India and China show salt alternatives are linked to lower blood pressure and fewer strokes, heart attacks, and deaths.

High blood pressure is easily detectable and treatable with medicines these days. But so many people don’t know that they suffer from it. It truly is a silent killer.

The randomized controlled trial studying a salt substitute in Telangana this year showed nearly a 5-unit systolic blood-pressure drop at three months of use of a sodium chloride- potassium chloride salt substitute. No one complained about the taste of the substitute either.

And the five-year large-scale study in China that was published in the New England Journal of Medicine two weeks ago is brilliant because it tracked a large cohort for a long time. There was statistically significant drop in deaths, cardiovascular events, and strokes with salt substitute use.

Why not consume less salt in the first place?

Excellent idea. A healthy diet, exercise, and weight control are ideal. But we’ve known this for decades now, and obesity and heart disease are on the rise. By layering many healthy choices- diet, medication (when needed), and an active lifestyle, we can lower overall risk, just as by layering many interventions during the pandemic (masks, social distancing, and vaccines) we can lower our risk of getting very sick from COVID-19.

But let’s also freely admit that our environments are stacked against us. Salt is tasty.

We need sodium in small amounts. Our ancestors evolved in the salt-poor African continent. Our taste buds craved salt when it was scarce, and now that it is abundant, we can’t keep our love of salty food under control.

There is no equivalent in the natural environment that has evolutionarily prepared us for a bag of potato chips- which combine fats with umami and salt. Processed and restaurant food are obvious culprits. You have no idea how much salt they add. And salt is addictive. It makes you thirsty, so you drink more at bars. It masks cheap and poor-quality ingredients.

Do I need to take a salt substitute?

Maybe you don’t. If your blood pressure is normal, you may be resistant to the effects of excess sodium. As I mention in my column, there are many people who consume sodium in the excess of guidelines without any detrimental effect; we don’t know how they do it, but they’ve likely won the genetic lottery.

What a salt substitute does (in theory at least) is that it reduces the risk of a bad outcome slightly for those of us at the risk of high blood pressure (and those who currently have it) by substituting something we enjoy with something else that tastes very much like it.

Should I take a salt substitute?

Ask your doctor if a salt substitute is right for you. You should not take a salt substitute with potassium if you have kidney problems, since hyperkalemia (high potassium in blood) might be a concern in your case. The accompanying editorial in the New England Journal of Medicine stopped short of advising everyone to take a substitute right now in anticipation of more clinical results. That said, the two studies did not report any adverse effects with salt substitute use. In particular, the one in China which ran for 5-years did not pick up any clinical cases of hyperkalemia (though they did not routinely check levels in the study groups).

To learn more…

If you want to learn more about salt, salt addiction, overuse, and its health effects I highly recommend this brilliant book written by Michael Jacobson and published by MIT Press.

To learn more about the salt substitute study in China, I highly recommend listening to this interview with one of the physician-scientists who led the study.

And now for something completely different…

Facebook, WhatsApp, and Instagram went out for a few hours on Monday, the same day that Ardem Patapoutian won the Nobel Prize for Physiology or Medicine along with David Julius. Patapoutian, who is Armenian by ethnicity, tweeted this out—