I just read an article in the New England Journal of Medicine that sparked my interest. It's in this week's issue, and it is about a computer simulation of the population health benefits of reducing dietary sodium. The article's title is "Projected effect of dietary salt reduction on future cardiovascular disease." Sounds pretty bland (pun intended), but bear with me.
Here's my brief summary of the article.
Americans eat way too much salt. Medically, most adults should eat 4 grams or less of salt per day. A low sodium diet is less than two grams per day. The average American man eats 10 grams and the average woman 7 grams of sodium per day. That's just way too much. Why? Because sodium raises your blood pressure, and high blood pressure increases your risk for bad things like coronary artery disease and stroke. It is difficult to reduce sodium intake because 75% of the salt in the US diet comes from processed foods rather than salt used in cooking or at the table. I'll admit, most of the time I don't look at the label on something I buy and check how much salt is in it. If I'm eating Cheetos, I know there is salt, and I don't want to know how much.
Previous studies have shown that decreasing the amount of salt in your diet by 1 gram per day causes a decrease in blood pressure of 1-2 points. Decreasing the salt by 3 grams decreases the blood pressure by 2-6 points. A one point blood pressure reduction doesn't seem to be a big deal. . . . but it is.
They ran their computer simulation (complicated, I don't understand the details. . . a lot of math words that I did not understand) on what would happen with different interventions to decrease dietary salt in the US and came up with huge effects. With interventions to decrease sodium intake by 3 grams, new cases of coronary artery disease would be reduced by 5-10%. Myocardial infarction would be decreased by 10-15%, and stroke decreased by 5-10%. These effects would be even greater in people who already have hypertension and in black men and women, who appear to be more sensitive to salt intake. I don't understand the details of how their model works, but this article was published in the most prestigious medical journal in this country and I am assuming that some smart people understand how it works and think it is reasonable.
They did a cost effectiveness analysis on different interventions, and found large savings in healthcare costs for each of the different salt reduction intervention scenarios. The scale they are talking is 4 to 90 billion dollars of healthcare cost reduction. They assumed that a population-wide regulatory approach to salt reduction would cost one dollar per person per year, as estimated by the WHO.
In our current climate of ballooning health care costs, any healthcare cost reduction would be a welcome change. Plus people would be healthier.
However, this brings into question- should dietary salt intake be regulated by the government?
My initial gut reaction says no. If people want to eat salt, let them. Just educate people.
But then, thinking more about it, making these changes will save huge amounts of money and prevent disease. Plus, some people don't want to be educated, or are unable to be educated, and if we just make these changes for them, everyone will be better off. Other countries including Japan and the United Kingdom have been able to reduce salt intake in their countries by regulating the salt content of processed foods, education, and labeling. So I'm all for it if it can be legislated.
In the meantime, I thought I would educate any of you out there reading this post still. Eat 2 grams of sodium per day and be healthy!
Bibbins-Domingo K et al. Projected effect of dietary salt reductions on future cardiovascular disease. NEJM 2010; 362:590-9