Biology

Your gut bacteria could be the key to fighting obesity

Your gut bacteria could be the...
The microbes in your gut signal your brain when you're full
The microbes in your gut signal your brain when you're full
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The microbes in your gut signal your brain when you're full
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The microbes in your gut signal your brain when you're full

Obesity is on the rise around the world, and if left unchecked this could have serious consequences for our overall health in the decades to come. However, it turns out that the bacteria living in your gut can help control how much food you eat ... which could change the way we all control our appetites in the future.

Gut microbes produce proteins capable of suppressing the appetites of mice and rats, and there is reason to believe the same process occurs in humans. A study conducted at France's Rouen University found that proteins produced by E. coli bacteria after they have been fed influence the release of signals to the brain, plus they activate neurons known to regulate appetite.

The authors of the study observed that after 20 minutes of consuming nutrients from food, E. coli present in the gut start producing different proteins. This coincides with the time it takes for an average person to start feeling full after a meal.

By injecting small doses of the bacterial proteins produced after being fed into the test subjects, they reduced their food intake. These proteins stimulate the release of peptide YY, a hormone closely linked to feelings of fullness. ClpB, one of the proteins produced when the gut bacteria have been satiated, also increases the firing of neurons that reduce appetite.

"We now think bacteria physiologically participate in appetite regulation immediately after nutrient provision by multiplying and stimulating the release of satiety hormones from the gut," says study leader Sergueï Fetissov. "In addition, we believe gut microbiota produce proteins that can be present in the blood longer term and modulate pathways in the brain."

A paper on Fetissov's findings was recently published in the journal Cell Metabolism.

Source: Cell Press

7 comments
Bob
It is becoming increasingly obvious that gut bacteria strongly affect our immune systems. It has been suggested that up to one half of all human diseases could be prevented with dietary changes. The study of diet has been sadly neglected.
Grunchy
Diet study has not been neglected by quacks, however. The most famous being Kellogg himself, but there have been countless others. I'm reading a fascinating book called "vitamania" which explores the simple story of vitamins, and the resultant multi-billion-dollar supplement industry. The author's conclusion: just eat normal food. (which is: meat, eggs, fruit, vegetables, grains, nuts, that sort of stuff).
Growling_M.A.D+Dirty
Then study the relationship between energy types in the food and the growth of different bacteria. It is more than certain that some (like ethanol yeast) thrives in sugar whereas others are better of with larger molecules. That means that the cells in the brain can control the food intake and therefore control the gut flora of bacteria. So which is strongest? The bacteria Or the cells in the nervous system We have heard the saying mind over matter. How deep does it go. This quack says - deep. Derp. Consciously decide what to eat and the gut flora will follow. Live unconsciously and let the gut flora dictate.
cwolf88
1. Fecal transplant treatments indicate that the microbiome affects obesity (thin donor to obese recipient results in fat loss; fat donor to thin recipient results in fat gain). However, no long term studies. Other work suggests that diet affects the microbiome mix, therefore simply adding the bacteria may not result in long term changes without dietary changes. 2. Any intervention has to be validated. In the USARIEM diet study (probably the best controlled one I've seen)(http://www.slideshare.net/James8981/health-performmilwomencbt1995), Subjects had significant micronutrient deficiencies on a "good" diet. Even well-done diet studies like the A-to-Z study often don't look at micro-nutrients or the microbiome so What You Measure Is What You Find (WYMIWYF) applies. 3. Therefore the prudent individual should do comp blood chemistry testing as the only way to objectively validate your diet, lifestyle, and micronutrient status. You can buy online.
Don Duncan
The correlation between obesity and health has been linked to eating habits. Since eating habits are highly addictive, especially the worst ones, psychological resistance to change is common. Many people choose to ignore irritating, unpleasant facts. "If I don't think about it, I won't have to deal with it" is the unspoken, unacknowledged pain avoidance mechanism. Pain is a warning, both when physical or mental. Confrontation of pain can be life saving. It is also less painful in the long run. People who choose short run avoidance sometimes forfeit the long run. They die younger than if they had chosen facing their pain. Read, study, think, repeat. The truth is out there, and it just might save your life.
AGO
The type of food we eat is what determines obesity overwhelmingly. The gut bacteria is essential to what nutrition is acquired through digestion. Most likely, a combination of healthy and nutritious whole food and a healthy gut combined is the greatest determining factor in health..... If only we could agree what a healthy diet is! My bet is on the diet we evolved eating which is lots of vegetation and healthy fats and protein with very few carbs (ketogenic)......
Bob
Another big piece of the obesity puzzle involves the food additives put in almost all of our food. When I raised cattle, I used to go to seminars about anabolic steroids and antibiotics to fatten my cattle to increase profit. Since we also ate our own beef, I decided to keep them range fed with some extra ground corn. I suspect that much of the obesity in our society is the result of everyone being fattened up by the additives in our food. We also used to rotate grain crops but no more. Pour on the chemical fertilizers, herbicides, and pesticides for more profit. We get food that is deficient in vitamins and minerals that they used to contain. Now read the additives put in any processed food you eat. What are the effects of all this? WE are told it is safe but who knows. One clue. How many of our children have asthma, allergies, diabetes, or autism? This will be like cigarettes. Until the evidence is so overwhelming no one will acknowledge the dangers.