People who eat a lot of highly salted food have double the risk of stomach cancer.
We already know that a high salt intake can lead to high blood pressure. A study, from Japan, reveals that salt increases the risk of stomach cancer as well. A group of 40,000 middle-aged Japanese was followed up for 11 years and their dietary and smoking habits recorded. The men with the lowest salt intake had a one in 1,000 risk of stomach cancer, while those with the highest intake had a risk of one in 500. For women, the risk was one in 2,000 for a low salt intake which rose to one in 1,300 if the diet was high in salt.
Salty foods, such as salted fish and pickled vegetables, are common in the traditional Japanese diet, and stomach cancer is the leading cancer in Japan, although it is on the decline. Interestingly, this decrease has followed a decline in the traditional diet and a move to a more westernized way of eating. Breast and bowel cancer are increasing in Japan, perhaps reflecting this dietary shift.
In Britain, stomach cancer is far less common than in Japan and consumption of Japanese-style salty foods is not widespread. The researchers are not yet sure whether it is the salt itself in these foods which is carcinogenic, or whether it is the combination of salt and other food ingredients.