Scientists urge food industry to cut salt to tackle obesity

Food manufacturers across Europe are already navigating stringent regulations to reduce salt in all products, so calls for further cuts will come as unwelcome news.

But that’s exactly what researchers from the Finnish Institute for Health and Welfare are proposing after discovering links between eating too much salt and an increased risk of obesity.

“High sodium intake cannot only be addressed at an individual level,” says Annika Santalahti, lead author on the study.

Santalahti believes changes are needed at the population level and can only be achieved through cooperation with the food industry.

Cut salt to cut obesity

Research, to be presented at the European Congress on Obesity (ECO 2025) in May, found that people with high dietary sodium intake were more likely to have general or abdominal obesity.

Women in the highest quartile of sodium consumption – 3,750mg of sodium per day – were found to be 4.3 times more likely to have general obesity and 3.4 times more likely to have abdominal obesity compared to women in the lowest quartile.

Women in the second highest quartile were 2.4 times more likely to have general obesity than women in the lowest quartile. Similar associations were observed when urine sodium concentration was used as an independent variable, suggesting the estimated sodium intake from food questionnaires and the amount in tested urine were in line with each other.

For men, while the pattern of increased obesity risk was similar to women for sodium consumption assessed by questionnaire, the results did not reach statistical significance across all quartiles. However, for urine sodium concentration, the results were statistically significant for men – those in the highest quartile of urine sodium concentration were six times more likely to have general obesity and 4.7 times more likely to have abdominal obesity compared to men in the lowest quartile in the fully adjusted model.

The results in men highlight the levels of hidden salts in foods that they are unaware they’re consuming.

“Contrary to popular belief, high sodium intake is not mainly caused by unhealthy foods, but by ordinary everyday food. In Finland, most sodium is obtained from processed meat products, bread and dairy products, especially cheese,” says Santalahti.

The researchers concluded that their results strengthen evidence of an association between sodium intake and obesity. Though they highlight the need for further research to establish the biological mechanism of the link.

“The association between salt intake and obesity is still very unclear, and there are no waterproof explanations for the differences between sexes nor for the phenomenon in general,” says Santalahti.

“Further research is needed on the overall nutrition and nutrition quality of those with high sodium diets, but also research on the biological mechanisms of high sodium intake, for example on satiety, the gut microbiome and body composition.”

General and abdominal obesity

General obesity is typically assessed using body mass index (BMI), with the World Health Organization (WHO) defining obesity as a BMI of 30 kg/m² or higher.

Abdominal obesity refers to excess fat accumulation around the abdomen and internal organs, resulting in an increased waist circumference. This type of obesity is particularly concerning, as it has been linked to a heightened risk of cardiovascular disease.

Role of the food industry

The researchers believe the food industry plays a “significant role” in reducing the population’s sodium intake, saying that the majority of food consumption comes from sources other than unprocessed primary production.

“It is important to pay attention to how salty commonly consumed daily foods are, as these account for a large proportion of the daily sodium intake,” says Santalahti.

Though she concedes that general changes in the food environment are also important, with factors such as individuals adding salt at the point of consumption also acting as a variable.