Salt makes almost everything taste better — we add it while cooking to enhance the flavor of other ingredients, sprinkle some into baking to balance out sweetness, and enjoy it in our favorite snacks, like chips, pretzels, and microwave popcorn. Besides these obvious sources, many highly processed foods — foods we wouldn't ordinarily consider salty — contain an unexpectedly high amount of sodium, such as canned goods, salad dressings, cold cuts, various cheeses, flavored yogurts, ketchup, and much more.
While lower salt consumption has long been recommended for people with cardiovascular issues like high blood pressure, researchers from the Finnish Institute for Health and Welfare have presented new research showing a strong link between higher sodium intake and the risk of obesity. This research is set to be presented at the European Congress of Obesity in May 2025.
Why We Crave Salt
Dietary salt, typically in the form of sodium chloride (NaCl), is necessary for essential bodily functions, such as regulating fluid balance and supporting nerve impulses and muscle contractions. When sodium levels drop, the "salt-thermostat" in our brain activates, triggering a craving for more salt.
Long ago, when our ancestors lived in oceans, the cells of those early lifeforms evolved to thrive in a solution as salty as seawater. As our predecessors became terrestrial and moved to dry, hot environments, salt became scarcer, and the craving for sodium likely developed as a survival mechanism to ensure adequate intake.
Today, that early evolutionary make-up, coupled with the easy access to salt that modern life provides, leads to plenty of opportunities for overconsumption. Studies have shown that when animals are deprived of salt, they often "overshoot," consuming far more sodium than necessary to restore balance, suggesting that salt homeostasis tends to go in only one direction.
Read More: Why Is the Ocean Salty?
Connecting High Salt with Obesity
A study led by Annika Santalahti and her team explored the growing body of evidence linking salt intake with obesity. They analyzed data from the National FinHealth 2017 Study, estimating sodium intake through food frequency questionnaires and urine samples.
Statistical analysis revealed that the median salt intake was above recommended levels, with men consuming over 12 grams and women over 9 grams daily. The World Health Organization recommends no more than 5 grams per day, while the American Heart Association suggests only 2.3 grams, about 1 teaspoon.
Additionally, the researchers found that participants with higher sodium intake or high urine sodium levels were more likely to suffer from general or abdominal obesity, with the latter increasing the risk of cardiovascular disease.
“These results strengthen the evidence of an association between sodium intake and obesity, with similar findings observed for both dietary sodium and urine sodium concentration. It is important to gain more understanding about the biological mechanism of the relationship,” said the study authors in a press release.
Processed Foods Are the Culprit
While the study emphasizes that the link between salt and obesity isn't fully understood, the authors note that, over time, high salt intake might affect satiety hormones (which control hunger and signal when we're full) or could simply serve as a marker for the overall quality of the foods we eat.
“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,” explained the authors in the news release.
They also point out that the food industry plays a significant role in the population's salt intake, as most of the sodium we consume comes from processed foods rather than unprocessed natural products. In addition, broader changes in the food environment, such as whether meals are home-cooked or consumed from restaurants or takeout, also influence how much salt we consume.
Read More: Salt Played a Pivotal Role in Ancient Human History
Article Sources
Our writers at Discovermagazine.com use peer-reviewed studies and high-quality sources for our articles, and our editors review for scientific accuracy and editorial standards. Review the sources used below for this article:
American Heart Association: Shaking the Salt Habit to Lower High Blood Pressure
European Association for the Study of Obesity: 32nd European Congress on Obesity
Physiology and Behavior: Salt craving: The psychobiology of pathogenic sodium intake
Having worked as a biomedical research assistant in labs across three countries, Jenny excels at translating complex scientific concepts – ranging from medical breakthroughs and pharmacological discoveries to the latest in nutrition – into engaging, accessible content. Her interests extend to topics such as human evolution, psychology, and quirky animal stories. When she’s not immersed in a popular science book, you’ll find her catching waves or cruising around Vancouver Island on her longboard.
