Explaining Leaky Gas

(If you want to jump to my successful Leaky Gas diet – here it is):

Put simply, Leaky Gas (LG) is gas that leaks out. For some people, the gas seeps out without their knowledge. They only know about this by comments people make. For the rest of us, we’re quite aware of the build-up of gas and its eventual leaking out. Holding it in is too painful.

Leaky Gas doesn’t seem to be considered a form of IBS by the researchers, but it’s really a form of IBS-C (constipation).

For most of us with LG, the problem isn’t necessarily “traditional” constipation where you’re blocked up for days. It’s more of an incomplete evacuation type of constipation. For me, this just grew progressively worse as I got older.

People with Leaky Gas have a predisposition to not being able to digest certain foods efficiently. These foods typically include grains, nuts and legumes, starch and FODMAPs. Manufactured starchy foods like breads etc are acellular and are typically difficult to digest for a lot of people. What these foods have in common is a concentrated, dry form of energy – carbohydrate or protein – that can resist breaking down by natural digestive enzymes or stomach acid.


Grains, nuts and legumes also contain anti-nutrients that resist digestion, such as lectins, phytates and opioid peptides. Some people are more sensitive to these chemicals than others. It’s not just carbs that are problem foods – meat also can ferment in the colon. Nearly all foods seem to be highly fermentable for people with IBS.

Carbohydrate is mostly digested in the small intestine and protein in the stomach, but if you lack enough stomach acid or Amylase enzymes you won’t be able to digest either protein or carbohydrate very well. Even if you have enough enzymes, up to 20% of animal protein escapes digestion in the stomach and this residue can putrefy in the colon.

This is where the gas comes from. It makes sense too, that if bacteria are constantly feeding on undigested food in the small intestine or colon, then those populations of bacteria will grow, either as Small Intestinal Bacterial Overgrowth (SIBO) or as general bacterial dysbiosis in the colon (large intestine).

Another complication is that gas itself can cause constipation. Dr Mark Pimentel pioneered a famous study which proved the link between methane gas and slow transit constipation.



The foods which are easy to digest tend to be low starch and low FODMAP vegetables, and a moderate amount of animal protein daily.

Anything that causes excess gas in the colon can cause Leaky Gas, because LG is just gas.

The reason why non-IBS people can eat FODMAPs, nuts, wheat etc and not get IBS symptoms is due to their ability to process the food more efficiently than we do. FODMAPs are mildly fermentable, even for normal people, but don’t produce the volume of gas that it does for us.

For me, excess gas from fermentation seems to block stool. I’m not sure how this works, but my diet (the link is above) cures this problem. If I follow the diet properly evacuation is complete and there is no more blocked gas in the colon.