Diet and Species Solve Mystery of H. Pylori and Gastric Cancer
The mystery is that Helicobacter pylori, a gram-negative bacterium species typically found in the stomach, has been linked with gastric cancer – specifically stomach cancer – yet most of the population of third world countries host H. pylori, with extremely low gastric cancer rates.
Some studies have shown that nearly all healthy children host the bacterium throughout the third world, and those countries with the highest H. pylori communities have the lowest rates of of gastric cancers.
Furthermore, the host rate of H. pylori infection among Americans has been going down dramatically over the past 50 years, and H. pylori infections have been are now extremely low. Those who do harbor the bacteria in America and other western countries have extremely higher risk of contracting stomach cancer. Over 800,000 stomach cancer cases occur each year worldwide.
Aside from these mysteries, the central mystery is why H. pylori does not have ill effects – including stomach and duodenal cancers – in over 80% of those populations infected by the bacterium.
This new Vanderbilt study may well bring together some of the missing pieces.
The researchers found that gerbils that hosted H. pylori on a high-salt diet had nearly double the rate of stomach cancer than gerbils infected with the same species of H. pylori who ate a normal diet.
Every gerbil on the high-salt diet contracted stomach cancer – yes, 100% – while only 58% of the normal-diet infected gerbils contracted the cancer.
This led the researchers to conclude that salt somehow exacerbates stomach cancer.
The puzzle came together when the researchers found that those on the high salt diet infected with another species of H. pylori – one that does not produce CagA, a oncoprotein secreted by certain species of H. pylori – did not contract stomach cancer.
In fact, none of the gerbils on the high-salt diet who were infected with a species of H. pylori that does not produce CagA came down with stomach cancer.
This meant that, first of all, that not only does CagA-negative H. pylori not cause cancer, but that a high-salt diet in the presence of a CagA-positive infection of H. pylori does produce stomach cancer – at an extremely high rate.
About 60% of isolated H. pylori species have been found to be CagA-positive among Western countries. But most of the third-world infections are of what is considered the Eastern strain of CagA-negative H. pylori.
This means that the Eastern species of CagA-negative H. pylori is actually not a pathogenic bacteria at all, but rather, a eugenic bacteria – not necessarily harmful or helpful to the host.
And it also means that the widespread infection of these hardy strains of CagA-positive H. pylori together with the highly processed and salty Western diet lies at the root of our high stomach cancer rates among Western countries.
A recent study from China’s Jinling Hospital found that CagA-positive H. pylori infections are growing among children in China – especially in Eastern China where much of the urban areas are.
So it appears that the infection rates of CagA-positive H. pylori are higher among those countries that eat predominantly a western diet, and infections rates are growing among countries who are increasingly eating a western diet.
Gastritis is also associated with CagA-positive H. pylori infections.
Written by Case Adams, Naturopath
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