Gastric cancer — also known as stomach cancer — is the fifth most common trusted Source of cancer in the world. While not as common in the United States, it still makes up about 1.5%Trusted Source of new cancer cases diagnosed annually.

Doctors and experts are interested in identifying risk factors for gastric cancer so that people can seek high-quality care early.

A recent study published in Gastric Cancer examined data from over 470,000 individuals to see how the frequency of adding salt to food related to cases of gastric cancer.

The authors found that participants who always added salt to food were at a higher risk for gastric cancer than participants who rarely or never added salt to food at the table.

This study adds to data about the risk salt poses for gastric cancer in non-Asian populations, as most research in this area has been in Asian populations.

As research moves forward, doctors may be able to ask people about their frequency of adding salt to foods as a simple indicator to monitor salt intake and related gastric cancer risk, aiding public health messaging.

This prospective study used data from the UK Biobank, including 471,144 participants in its analysis.

They excluded participants who were missing data on adding salt to food, body mass index (BMI), or urinary sodium or potassium levels. They also excluded participants who had cancer at baseline and participants who had kidney disease.

Participants filled out baseline questionnaires to indicate how often they added salt to food, excluding the salt they used while cooking. Participants could respond with never/rarely, sometimes, usually, or always.

Researchers further measured participants’ urinary sodium, creatinine, and potassium levels. They were also able to estimate 24-hour urinary sodium excretion.

They accounted for several covariates, including physical activity levels, age, education level, ethnicity, sex, and alcohol use. They were also able to take into account red meat consumption and fruit and vegetable intake. The median follow-up period with participants was 10.9 years.

During the follow-up time, 640 cases of gastric cancer among participants were documented. In general, participants who reported always adding salt to food at the table were more likely to be past or current smokers, have a high level of alcohol intake, and have a lower education level.

Researchers found that participants who always added salt at the table were at 41% higher risk for gastric cancer compared to participants who never or rarely added salt to food at the table.

While they found that adding salt to food more often was associated with increased 24-hour urinary sodium levels, they did not find a significant association between 24-hour urinary sodium levels and gastric cancer.

They also found that in a subset of 198,900 participants, responses to the frequency of adding salt at the table positively correlated with daily sodium intake levels.

The results suggest that examining the frequency of added salt use at the table may be a simple way to assist in identifying individuals with high salt intake who may, in turn, be at risk for gastric cancer.

Anton Bilchik, MD, PhD, surgical oncologist, chief of medicine, and Director of the Gastrointestinal and Hepatobiliary Program at Providence Saint John’s Cancer Institute in Santa Monica, CA, not involved in this study, told Medical News Today “[t]he study provides further evidence of the association 

between diet, particularly one rich in salt and gastric cancer.” He added:

“It has been suggested that one of the major causes of gastric cancer in Asian countries is from fish high in salt content. Much less is known about the association of salt intake and gastric cancer in Western countries. It is well known that excessive use of salt is associated with a higher risk of hypertension and cardiovascular disease. This study provides additional evidence that salt routinely taken with meals increases the risk of developing gastric cancer. It is therefore imperative that people be aware of the deleterious effects of excessive salt intake.”

Many factors contribute to someone’s risk for gastric cancer, including smoking, increased age, obesity, and family history.

Researchers of the current study note that higher salt intake has been associated with a higher risk for gastric cancer in Asian studies.

However, there have not been many studies in this area among Western population groups.

Bilchik offered the following insight to MNT:

“Gastric cancer is very serious especially if it presents at an advanced stage. It is one of the most common cancers in Asian countries and there is therefore greater emphasis on screening measures than in Western countries. Also, the pattern of presentation is different with patients from Western countries presenting more often with cancer in the upper part of the stomach, a more challenging location to manage than Asian countries where cancers are more often found in the lower part of the stomach. This may be related to a higher incidence of obesity and gastroesophageal reflux disease in Western countries — risk factors for upper gastric cancer.”