People with less money eat more salt than wealthier people living in the same regions, found a new British study, suggesting that social inequalities reverberate in complicated ways through our dietary choices and health consequences.
High sodium intake is linked to high blood pressure, which increases the risks of cardiovascular disease. And both high blood pressure and related diseases tend to be higher in socially disadvantaged groups of people.
For the new study, researchers from the University of Warwick in the United Kingdom used data collected on more than 2,000 people in a national dietary survey conducted in 2000 and 2001. Most of the participants kept a food diary for seven days. The researchers also tested sodium levels in their urine over a 24-hour period.
Overall, the researchers reported in the BMJ Open journal, people in Scotland ate more salt than people in England or Wales.
But when the scientists broke down the data by demographics, they found that, within the same geographic regions, salt consumption was highest in people with the lowest levels of education and in those who did manual labor. Both are signs of low socioeconomic status.
The vast majority of salt that people eat – in the U.K., the United States and other developed countries – is hidden in processed and restaurant foods. And people with fewer resources are more likely to depend on those cheap yet sodium-rich foods.
Most people consume double the amount of sodium that's recommended by governmental organizations. And because of salt's links to cardiovascular disease, the researchers wrote, "it is estimated that a 15 percent reduction in salt intake would avert 8.5 million deaths over 10 years worldwide."
By tracking unequal patterns of consumption, the researchers hope to influence public policies that would reduce sodium levels in everyone's diet.
"The diet of disadvantaged socioeconomic groups is made of low-quality, salt-dense, high-fat, high-calorie unhealthy cheap foods," the team wrote. "An effective way to reduce salt intake across all socioeconomic groups is to gradually reduce the salt content in food, such as bread, a major source of salt, because most of the salt intake is hidden in processed food."