Diet Promotes Stomach Cancer

For the first half of the 20th century, stomach cancer killed more Americans than any other cancer. Today stomach cancer still afflicts over 20 thousand Americans and kills over ten thousand but the incidence has dropped more than 10-fold over the last 70 years. This huge reduction in stomach cancer cases in the US was largely inadvertent and certainly not due to an early diagnostic test and/or new wonder drugs or surgical interventions. Research now shows that most stomach cancer is due to the intake of highly salted, smoked, cured, and fermented foods. Salt damages the stomach lining leading to atrophic gastritis in the long run. High-salt intake also enhances the growth of a more virulent strain of H. pylori in the stomach. This bacteria is also believed to contribute to a reduction of stomach mucus and the destruction of the acid producing parietal cells that protect the stomach from a wide variety of cancer promoting chemicals. It is believed stomach cancer rates have dropped markedly in the US as refrigerators reduced the reliance of most Americans on highly salted, cured and smoked meats and pickled and canned foods vegetables. Also at about the same time there was a marked increased use of antibiotics that no doubt inadvertently reduced the number of Americans with H. pylori infections. Since H. pylori was shown to be the cause of most ulcers and gastritis in the 1980s there has also been a growing interest in treating these people with antibiotics to wipe out their H. pylori infections over the past 25 years.1Despite the largely inadvertent success of preventing stomach cancer in the US, it remains the #2 cancer killer worldwide. Stomach cancer is the #1 cancer killer in China killing about 300,000 each year. It is also the #1 cancer killer in several other Asian and Latin American countries and ranks second only to lung cancer in other countries. It is estimated that eliminating H. pylori infec- tions could reduce the incidence of stomach cancer by about 60%.2 However, widespread use of antibiotics to eliminate H. pylori would likely lead to the development of drug resistant strains given that over half the world’s population is infected with H. pylori. Also in people who have had H. pylori infections for many years and already have precancerous lesions there seems to be little benefit in treating the H. pylori infection. It seems far more cost effective to focus public health efforts on reducing the consump- tion of salted, pickled, smoked, fermented and cured foods. Elimination of such foods from the diet would also likely help reduce the risk of stomach cancer in older people who have already developed atrophic gastritis by reducing the amount of cancer promoting agents in the stomach.While certainly not mutually exclusive the dietary approach to reducing stomach cancer by reducing the intake of cancer-promoting foods appears potentially far more cost effective and less fraught with potential adverse effects than the medical treatment of all asymptomatic individuals infected with H. pylori with antibiotics. In those who have ulcers and/or gastritis due to H. pylori infection the use of antibiotics to wipe out those infections seems medically justified even though we are already seeing antibiotic resistant strains of H. pylori developing in the US as a result. Also these potent antibiotics can sometimes increase the risk of other problems like increased CVD events, severe allergies, and other side effects. By contrast, cutting back on the use of highly salted, pickled, smoked, and fermented foods in US would not only further reduce morbidity and mortality from stomach cancer but more importantly would also help to dramatically reduce blood pressure and cardiovascular events. Worldwide cardiovascular disease kills far more people than stomach cancer. In the US alone there are about 700,000 strokes, nearly 1.5 million heart attacks, and over 300,000 new cases of heart failure each year. These could be cut dramatically by cutting way down on salt-rich foods. High blood pressure alone appears to account for about half of all cardiovascular disease in the US and also worldwide. Reducing salt-rich foods could also cut the 75,000 or so new cases of kidney failure each year in the US and reduce the loss of calcium in the urine that contributes to kidney stone formation and osteoporosis.Bottom Line:The inadvertent success of dramatically reducing stomach cancer incidence in the US and in other countries where the reliance on salt to preserve foods has been reduced shows that dealing with the cause of cancer rather than trying to diagnose it early and treat it with drugs and surgery can be far more efficacious and far less costly than the current medical paradigm that passes for cancer “prevention” in the US.By James J. Kenney, PhD, FACNReferences:1. World J Gastroenterol 2009;15:2204-132. Lancet;2011:378:2011:507-14