Lower-Income Americans at Higher Risk of Death From Excess Salt

5 min read

April 2, 2024 – Eating food with high amounts of salt has long been linked to a greater risk of high blood pressure and heart disease. But much of the research on salt’s effects have been with middle- and upper-income populations. 

A study says large portion of low-income African Americans and White Americans exceed the current recommended sodium intake level. So why is this population getting too much salt? 

“In this marginalized group, it is almost always consistent with food access,” said Lena Beal, a registered dietitian nutritionist and a spokesperson for the Academy of Nutrition and Dietetics. Lower access to healthier food involves few options outside of convenience foods, a lack of education about healthier food choices, and problems being able to afford quality food, she said

Salt is a necessary nutrient, but a diet with too much of this good thing is linked to death from heart disease.

A large portion of low-income African Americans and White Americas exceeded the current recommended sodium intake level in the new study, “which may have contributed to their high cardiovascular disease mortality rate,” said senior author Xiao-Ou Shu, MD, PhD, a researcher in the Department of Medicine, Division of Epidemiology at Vanderbilt University Medical Center in Nashville. Cardiovascular disease is a term for problems with your heart and blood vessels.

About 80% of the 65,000 people in the study got more than the daily recommended amount of salt (or sodium) in their diet. The federal government recommends 2,300 milligrams or less per day. In contrast, Black Americans consumed an average of 4,512 milligrams of sodium in their diet per day, while low-income White Americans consumed an average of 4,041 milligrams daily. 

Overall, having too much sodium in their diet was linked about 10% to 30% of cardiovascular disease deaths in the study, which was published online March 26 in the journal JAMA Network Open. 

Barriers to Healthier Foods

“It's a solid study. We see this often in our everyday practice, so it's good to have a study that supports it,” said Beal, who was not involved in the research. 

“We have our urban food deserts in Atlanta, where there's no grocery store within walking distance or one easily accessible using public transit, so people end up shopping at the proverbial corner store,” said Beal, a cardiac dietitian at Piedmont Atlanta Hospital.

“The barriers for that population are very real and palpable when you're dealing with them every single day,” she said.

According to the city of Atlanta, just 52% of city residents lived within a half-mile of fresh food in 2015, a figure that increased to 75% by 2020. The city has set a goal of upping that to 85% by 2025. 

Moving forward, Beal would like to see more action. “We have got to put some muscle time, energy, research dollars, and resources into these communities to increase their access to wholesome, healthful choices at affordable prices.”

Excess Salt, Excess Death Risk

Shu and colleagues examined patients a median of 14 years after they entered the Southern Community Cohort Study. People ages 40 to 79 were enrolled in the study between 2002 and 2009, mostly from health centers serving underserved Americans in one of 12 Southern states. They were 72% Black and 28% White, and about 83% lived in households with an annual income below $25,000.

After controlling for other things that can increase heart disease risk, the researchers found that every 1,000-milligram increase in salt over the recommended 2,300 milligrams per day was tied to a greater risk of death.

For example, among Black patients, this added a 3% increased risk of dying from any reason, 7% higher risk from total cardiovascular disease, and an 8% higher chance of dying from congestive heart disease. Among White patients, the risks were even greater – an added 8% likelihood of dying from total cardiovascular disease and a 13% higher risk of death from congestive heart disease. This group also was 55% more likely to die from heart failure. 

And the issue is not just among Americans with lower socioeconomic status. Americans overall consume high levels of dietary salt – an average of 3,400 milligrams a day. 

Myths and Potential Solutions

People have multiple misperceptions about excess salt, Beal said. On the medical side, they tend to misunderstand “the strong correlation with heart disease, and on the diet side, people misunderstand how simple it is to address.” 

Avoiding excess salt does not mean eating food with no taste. Rather than sprinkling on the salt, add herbs and spices, Beal suggested. For example, instead of eating rice that comes in a box with a seasoning packet that you boil and serve, choose rice in a bag that you boil and season yourself.

Shu said that “a special program aiming to educate the health risk of high sodium intake and promote healthy diet among these vulnerable populations should be a public health priority.”

Beal encourages people to change their lifestyle in two ways, even if they are financially restrained. “It's going to be how much or how often you do something – the amount or the frequency.”

The “how much” means portion control. The “how often” means the number of times you eat prepackaged products, convenience foods, or processed foods. Restaurant food can include unknown amounts of salt, too, especially fast food.

Choose to buy 100% fruit drinks instead of dark sodas, Beal suggested. Opt for smaller bottles – buy a drink that is 8 ounces instead of 20 ounces. Buy ramen noodles and drain the liquid off before eating. In addition, limit condiments and sauces like barbecue sauce, ketchup, and mayonnaise, which “have all the excess sodium and sugar.”

Study Limitations and Strengths

Shu and colleagues calculated salt in the diet based on what people reported at one time, when they entered the Southern Community Cohort Study. So any changes over time could not be considered. Also, self-reporting salt in the diet might be less accurate than testing blood or urine samples. 

In terms of strengths, Beal cited the large sample size and the focus on underserved communities.

Asked about next steps, Shu said their plans include looking into how genes affect the way sodium impacts health.