Adding salt to your dinner plate may increase cancer risk
Key Takeaways
A large, UK-based study found that those who always add salt to food have a 41% increased risk of developing gastric cancer.
Eating large amounts of salty foods, like salted fish and meat and pickled vegetables, is a known risk factor for stomach cancer.
Experts say physicians should counsel their patients to reduce salt intake.
Always adding salt to food is associated with a 41% increased risk of developing gastric cancer.[]
Research published in Gastric Cancer found that among a large sample of more than 500,000 adults, those who always added salt to their food had a greater risk of developing gastric cancer than those who never or rarely added salt.
“Our findings on ‘always adding salt to food’ at table and gastric cancer are in line with the findings of a recent pooled analyses of 25 case–control studies conducted in America, Asia and several European countries, which showed positive associations between added salt and gastric cancer,” the study authors write.
“They are also in line with findings from a recent meta-analysis of prospective studies showing higher gastric cancer risk among Asian populations with high intakes of salt, salted fish, pickled foods and processed meats, used as proxies of total salt intake among study participants.”
The researchers examined data from the UK Biobank, a large population-based prospective study involving adults in the United Kingdom.
Participants were asked whether they added salt to their food but were asked to exclude any salt used in cooking. The participants could choose between “never/rarely,” “sometimes,” “usually,” “always,” and “prefer not to answer.”
Those who reported “always” adding salt to food were more likely to have a lower education level, be male and non-white, have high alcohol intake, and be a past or current smoker.
In models adjusted for socioeconomic, demographic, and lifestyle factors and for prevalent comorbidities, participants who always added salt to their food had a greater risk of developing gastric cancer.
Anton Bilchik, PhD, a surgical oncologist and Chief of Medicine and Director of the Center for Gastrointestinal and Hepatobiliary Tumors at Providence Saint John’s Cancer Institute in Santa Monica, CA, says there are a number of possible reasons why salt could influence gastric cancer risk.
“There are a couple theories that salt itself can influence or affect the lining of the stomach, resulting in a change in the cellular architecture. The other theory is that it has a direct effect on Helicobacter pylori, and H. pylori is a bacteria that has been shown to cause stomach cancer. [T]here is data to suggest that salt can increase the effect of H. pylori, resulting in stomach cancer, but overall there are likely to be many other reasons that are still unproven or unknown,” Bilchik tells MDLinx.
Stomach cancer is the fifth most commonly diagnosed cancer in the world.
In the United States, gastric cancer accounts for roughly 1.5% of all new cancers diagnosed annually.[]
Eating large amounts of salty foods, such as salted fish, meat, and pickled vegetables, is a known risk factor for stomach cancer.[]
“We have always known that a high-salt diet increases your risk of developing gastric cancer. Gastric cancer used to be much more prevalent in the US and Europe in the early 1900s, which was attributed, in part, to the lack of refrigeration and the need to preserve food with salt. We believe that one of the reasons for the significant decline in the incidence of gastric cancer has been the decreased salt content in food,” Joo Ha Hwang, MD, PhD, a professor of medicine in gastroenterology and hepatology at Stanford, tells MDLinx.
Gastric cancer has the highest prevalence in Asia, Eastern Europe, and Latin America.[]
But Dr. Hwang says it is important that physicians in the US take steps to identify gastric cancer in its early stages.
“Gastric cancer in the US is not [as] rare [a] disease as many physicians think. There are very high-risk populations in the US—primarily immigrants from high-prevalence regions/countries, such as East Asia (especially Korea and Japan), Eastern Europe, and parts of South America,” he tells MDLinx.
“Gastric cancer can be cured if identified at an early stage, but patients who are at high risk need to be tested for H. pylori infection and screened with endoscopy. They should also be counseled to minimize salt intake, as supported by this study. We still need some salt in our diet, though. Salt, inherently, is not bad. We should avoid too much salt.”
What this means for you
A large study from the UK has found that people who always add salt to their food have a 41% greater risk of developing gastric cancer. Eating large amounts of salty foods, like salted fish and meat and pickled vegetables, is a known risk factor for gastric cancer. Physicians should be aware that gastric cancer is not as rare in the US as is often believed—and that immigrants from high-prevalence regions like Asia and Eastern Europe are at greater risk. Physicians should counsel patients to reduce their salt intake.