Do H. Pylori Prevent Obesity?

[tex]

Hi All,

Could the regulation of body weight be the reason why they exist in our stomachs? The evidence seems to suggest that could be the case:

After a meal, levels of ghrelin, a hunger hormone secreted in the stomach, are supposed to fall. But in subjects without H. pylori, the amount of ghrelin in the bloodstream held steady, in essence telling the brain to keep eating.

Moreover, mice in Dr. Blaser’s lab fed antibiotics in dosages similar to those given to children to treat ear and throat infections — which is enough to kill H. pylori in many patients — had marked increases in body fat even though their diets remained the same. (Indeed, farmers have long given antibiotics to livestock to promote weight gain without increasing caloric intake.)

http://www.nytimes.com/2011/11/01/healt ... .html?_r=1

Hmmmmmmmm. Maybe all "bad" bacteria are not so bad after all.

Tex

[Lesley]

How do I get them to do what comes naturally and proliferate? *WEG*

[tex]

Those are uncharted waters.

Tex

[Gayle]

I would personally be loath to buy into such theory --

Neighbor, good friend, in AZ recently diagnosed with something called MALT lymphoma. This after many months of non-adequate medical attention to major symptoms such weight loss, diffulty swallowing any/all solid foods, and eventual pneumonia (probably aspiration pneumonia due to her difficulty swallowing food). They tried treating her constellation of symptoms with tranquillizers.

Eventual diagnosis = "MALT Lymphoma", which if one reads about it, is thought to be H-pylori related. This form of lymphoma is sometimes treatable with the same antibiotic therapy used to treat H-pylori. However -- now due to long standing nature of her unmanaged H-P infection, she is now needing chemo.

Gayle

[tex]

Gayle,

It's well known that individuals infected with H. pylori have an increased risk of gastric mucosa-associated lymphoid tissue lymphoma, but it's still a rare cancer of the stomach. But did you know that individuals infected with H. pylori have a reduced risk of gastric cardia cancer, esophageal adenocarcinoma, and GERD? Did you know that the evidence suggests that H. pylori may protect against asthma, metabolic syndrome, type II diabetes, and, (as I mentioned in my original post), obesity?

In a perfect world, your aversion to H. pylori would be understandable - but we don't live in a perfect world. Everything has advantages and disadvantages - nothing is perfect. All food, for example, contains lectins, so we can't avoid them, much to our chagrin. The best we can hope for in every situation, and in every association with other organisms, is that the benefits outweigh the risks. With H. pylori, it appears that the benefits do outweigh the risks. The quote below comes from an article titled "Who are we? Indigenous microbes and the ecology of human diseases", which can be read in it's entirety at the link below. I've highlighted the symbiotic effects of H. pylori in red, for easier reference:

The second example is the interaction of the gastric bacterium Helicobacter pylori with humans, and the consequences of ending this intricate and longstanding relationship. In fact, H. pylori can be regarded as a paradigm of how changes in indigenous microbiota affect human health (Fig 2). Studies of the gastric helicobacters in other mammals, and of human migration patterns over time (Ghose et al, 2002; Falush et al, 2003), suggest that theforebears of modern H. pylori have been present in our ancestors since well before we became humans. The bacterium is also of interest because diagnostic tools are now able to determine its presence or absence in the human stomach, and epidemiological methods can study its effects on human health. Although H. pylori was once present in almost every adult human, the bacterium is now rapidly disappearing from human populations owing to changes in sanitation, demographics and antibiotic usage. Today, fewer than 10% of children in the USA harbour this bacterium in their stomach. When present, H. pylori is the single dominant species in the stomach (Bik et al, 2006), so its disappearance is potentially significant. Through its pro-inflammatory effects, H. pylori modulates immunological, endocrine and physiological functions in the stomach (Blaser & Atherton, 2004), with both local and systemic manifestations (Fig 2). The biological costs of carrying H. pylori include peptic ulcers and adenocarcinoma of the distal stomach. The (cag+) strains that interact to the greatest extent chemically with their hosts convey the highest risks. Conversely, these strains also protect against gastroesophageal reflux disease (GERD) and its consequences, including oesophageal adenocarcinoma, owing in part to their effects on gastric-acid secretion (Peek & Blaser, 2002). These observations are consistent with the rise of these diseases wherever H. pylori is disappearing, and therefore provide the first definitive example of a group of chronic diseases caused by changes in the human microbiota. GERD has been linked to asthma, and preliminary results now support a link between the disappearance of H. pylori and the increase in asthma cases. In addition, H. pylori affects gastric hormones that have a role in energy homeostasis, such as leptin and ghrelin; a link between its disappearance and the increasing prevalence of metabolic syndrome, type II diabetes and obesity has also been postulated (Blaser & Atherton, 2004).

http://www.nature.com/embor/journal/v7/ ... 400812.pdf

Every organism has a reason for existence, and in the case of virtually all of the microbes that share our body with us, that reason is symbiosis. The bottom line is, in rare instances, H. pylori can increase the risk of a rare type of cancer, but in the vast majority of cases, it apparently provides numerous significant benefits to offset that tiny risk.

Tex

[Stanz]

That is a fascinating article, Tex, thanks for posting.