There is a switch inside you that turns appetite off.
GLP-1, released normally after a meal, is a switch that gives satiety and calms impulse. When it turns off, the emotional center is pulled around by dopamine.
GLP-1 on
Satiety, restraint, calmed impulse. After eating you feel satisfied and can stop.
VSC-producing bacteria turn off the switch
When VSC-producing bacteria suppress GLP-1 secretion, limbic dopamine surges — loss of appetite control, night eating, stimulus-seeking.
Not being able to resist food may not be a problem of willpower. With the satiety switch turned off by bacteria, dopamine keeps demanding no matter how much you resist.
It starts with diet and ends in impulse.
Poorly-digestible diet + sulfur
Fiber, whole grains, fermented foods, garlic become colonic fermentation fuel.
VSC-producing bacteria overgrowth → sulfur gas
VSC-producing bacteria multiply, making H₂S and methyl mercaptan.
GLP-1 suppression
Secretion of the satiety hormone is pressed down.
Limbic dopamine surge
Leading to failure of appetite control and difficulty with impulse.
Turn the switch on, but the fuel remains.
GLP-1 drugs (Wegovy, Mounjaro, and others) turn this switch on artificially to suppress appetite. But without also addressing the bacterial overgrowth and its substrate (fuel), side effects and relapse can follow as long as you keep eating whole grains and salads.
Cases have been observed where a low-fiber, refined-carbohydrate meal stabilized dopamine. This does not mean "soda is good" — the point is that keeping bacteria from hijacking the limbic system is what matters.
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The English-language writing on GLP-1, the limbic system, and the gut origins of cravings lives on Substack.
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