- Studies have linked a high intake of table salt with an increased risk of mortality, but recent data has been conflicting.
- A new study suggests that a higher frequency of adding salt to cooked meals was associated with a higher risk of premature death and a shorter life expectancy.
- Higher fruit and vegetable intake attenuated or weakened this association between salt use and increased mortality risk.
- Adding salt to foods at the table accounts for 6-20% of daily sodium intake, and limiting the use of salt at the table may have health benefits.
A recent study published in theeuropean journal of the heart shows that people who always add salt to cooked meals had a 28% higher risk of premature death than those who rarely add salt. A higher frequency of adding salt at the table was also associated with a shorter life expectancy.
Dr. Lu Qi, an epidemiologist at Tulane University and lead researcher on the study, said: “This is the first study to show that adding salt to meals is linked to an increased risk of premature death and shorter life expectancy. . Adding salt is a behavior that could be modified; therefore, our findings suggest that behavior modification by reducing the addition of salt to food may be beneficial to human health.”
Several studies have shown that a
However, other studies have shown
Other researchers have used dietary surveys or food records to estimate daily sodium intake. These methods are error-prone due to challenges associated with accurately measuring amounts of food consumed or study participants’ failure to report use of condiments or table salt.
Additionally, estimating sodium intake due to processed food consumption using dietary surveys can be challenging due to variation in sodium levels in the same food product from different brands. Processed, prepackaged, and restaurant-prepared foods account for about 70% of
Another drawback of using dietary surveys is that they may miss the effects of potassium intake. Many foods that contain high levels of sodium also contain high levels of potassium. Higher potassium levels are beneficial to health and may reduce the adverse health impacts of high sodium intake. Since table salt is primarily composed of sodium chloride (97-99%), assessment of the frequency with which salt is added to foods can provide a measure of sodium intake independent of potassium intake.
Because of these difficulties in quantifying sodium intake levels, the current study evaluated the link between how often people added salt to their food and mortality risk. The researchers of the current study noted that previous studies have shown that the frequency with which salt is added to food can indicate a person’s long-term preference for salt. Furthermore, such salt-using behaviors are less susceptible to daily variations in salt intake.
The present study consisted of data from over half a million people with an average age of 57 who volunteered to share their health data with the UK Biobank database. The researchers used a questionnaire to determine how often the participants added salt to cooked meals.
Based on their response, participants were categorized as never/rarely, sometimes, usually, or always using table salt. The researchers also obtained urine samples from the participants to assess urine sodium and potassium levels at the start of the study.
The researchers found a positive correlation between the frequency of adding salt and the concentration of sodium in the urine. In contrast, a higher frequency of adding salt was correlated with lower urine potassium levels.
The frequency of adding salt to food was also associated with the levels of sodium excreted in 24 hours, estimated from the urinary sodium levels measured from the urine sample.
The association between the frequency of adding salt to food and urinary sodium levels suggests that an individual’s habit of adding salt to food may reflect their long-term preference for salt.
The researchers used mortality data from national registries to track participants’ deaths during the follow-up period of about nine years. They classified deaths under 75 as premature.
After controlling for variables such as age, gender, diet, pre-existing medical conditions and physical activity levels, the researchers found that a higher frequency of adding salt to food was associated with an increased risk of premature death from all causes and a shorter life expectancy. Compared with people who never or rarely added salt to their food, always adding salt to food reduced life expectancy by 1.5 years in women and by about 2.3 years in 50-year-old men.
While examining the link between table salt use and cause-specific mortality, the researchers found that a higher frequency of adding salt was associated with an increased risk of premature death from cancer and cardiovascular disease. Among cardiovascular disease subtypes, people who frequently added salt to their food had an increased risk of premature death from stroke, but not from coronary heart disease.
Notably, among people who ate higher amounts of fruits and vegetables, a higher frequency of adding salt to meals was not associated with an elevated risk of premature death. These results suggest that the consumption of foods rich in potassium, such as fruits and vegetables, could attenuate the effects of adding salt to food on mortality.
Dr. Francesco Cappuccio, professor of cardiovascular medicine and epidemiology at the University of Warwick, pointed out that salt added when cooking food may play a more important role than salt added at the table.
“Salt intake is the result of salt added to food at the table (estimated here), salt added to food during cooking (not measured here), and, most importantly, hidden salt in food. processed and foods consumed outside the home, the latter exceeding 75% of the total intake,” said Dr. Cappuccio.
“The frequency of adding salt to food reflects an individual’s long-term salt preference is a myth that is not supported by evidence. Randomized trials in Australia showed that most salt shaker use is completed ‘before’ the food is tasted, and reducing the hole size means less salt is added, indicating that table use of the salt shaker is not related to salt intake. flavor preference. Dr. Cappuccio added.
“Furthermore, if the salt content of commonly eaten foods, such as bread, is reduced gradually over time (i.e., 10% per week or month), salt reduction can be achieved without consumers detect salinity,” he explained.
Dr. Cappuccio noted that awareness campaigns to change behaviors to reduce salt intake have short-lived positive effects. Regulating industries to reduce the salt content of foods could be a more effective means of reducing salt intake in the population.
Furthermore, this study only shows an association between table salt use and mortality and does not establish causality.
Dr. Franz Messerli, professor of medicine at the University of Bern, Switzerland, said: “The difference in 24-hour sodium intake between those who never or rarely added salt and those who always did is minuscule 0.17 g less than 4%…. It is highly unlikely that such a negligible amount would have any impact on blood pressure, let alone cardiovascular mortality or life expectancy.”
“I contend that people who routinely add salt to their food exhibit a pervasive disregard for health considerations in their diet. These study participants consistently consumed more red meat, processed meat, less fish, fewer fruits and vegetables than those who did not salt their food,” explained Dr. Messerili.