SuttaCentral
Just wondering if this is even legit at all… i noticed when i do Vipassana meditation… i tend to fart during and after it alot?
I’ve heard of this happening before by others. So just wondering if anyone also faces this? If so, what’s the connection and logic for it?
I’d guess it’s because meditation (and other calming states) tends to activate the parasympathetic nervous system, which plays a big role in activating the “rest and digest” state.
Or maybe you need to cut down on the legumes. 
One unfortunate theory might be that you’re actually farting all of the time, wherever you are and with whomever you’re with. With vipassana, you’re just “noting” this, mindful and aware. 
Haha… i don’t eat legumes or beans!
On the other hand on another experience,
I was quite sure i didn’t eat any bad food before hand. I took a couple of suspicious food i think is spoilt at 8pm. I followed a guided vipassana meditation to view the body and pushing the breathe around the body.
2 hours later i sensed a pain from my the stomache area below solar plexus… the pain increased and i went to the toilet… releasing unusual diarrhea.
I’m thinking, doesn’t food take at least 8 hours to pass through our body? So could the diarrhea be because of the spoilt food i took… or did meditation helped to purge something bad out of me?
Read Bhante Sujato’s essay on the topic: Finally, some fun meditation: mindfulness of farts
And again here: Mindfulness of Farts — Revisited
I’m no expert, but yeah 2 hour transit time from mouth to anus doesn’t seem likely with solid food. It’s possible the ingestion of the possibly spoiled food triggered the diarrhea of whatever was in your colon from your previous meals. Or maybe you have IBS, given the diarrhea and all the flatulence. I dunno. I wouldn’t worry about it unless it becomes a problem in which case you should see your doctor.
I wouldn’t call farting ‘unfortunate’ , rather ‘nessessary, funny and thourourly pleasurable’.
Edit: even if those who didn’t deal it might not exactly find it pleasurable, they usually laugh at the noise or smell , which is surely better than nothing 
Gas emission, whether from the bottom or top, is treasure. That is said in complete seriousness, and with no exaggeration. The better your meditation gets, the more you’ll see the connection. Even doing coarse types of exercise will stimulate gas emission, but doing the internal arts, jhana, meditation, taiji quan, yoga, when the mind is an a-vitakka-a-vicara (no thinking, no evaluation) samadhi, internal forces within the body pervade the whole body, gradually loosening, eroding, and eliminating all energetic blockages. Every fart you take, some parts of your body are going to feel a little looser, a little lighter, a little more refined.
Old people especially with weaker health and constitution, a fart can be the difference between extreme sharp pain and blissful pain relief. Knowing some good accupressure points to push can also release gas.
I believe secular Buddhists could use this to explain the phenomenon of “levitating” yogis!
For some reason this reminded me of a song by The Police, “Every breath you take.” 
I think you may have experienced the wind property!
"And what is the wind property? The wind property may be either internal or external. What is the internal wind property? Anything internal, belonging to oneself, that’s wind, windy, & sustained: up-going winds, down-going winds, winds in the stomach, winds in the intestines, winds that course through the body, in-and-out breathing, or anything else internal, within oneself, that’s wind, windy, & sustained: This is called the internal wind property. Now both the internal wind property & the external wind property are simply wind property. And that should be seen as it actually is present with right discernment: ‘This is not mine, this is not me, this is not my self.’ When one sees it thus as it actually is present with right discernment, one becomes disenchanted with the wind property and makes the wind property fade from the mind. MN140
with metta
These gas threads keep coming up, don’t they? 
Better out than in, I suppose. 
It’s a lot of hot air if you ask me!
With metta
These days science talks about the “enteric nervous system” (ENS, along with the traditionally recognized CNS (central…), PNS (peripheral…) and ANS (autonomic…)) – a virtually self-sufficient nervous system in the digestive system.
It’s quite possible, even empirically verifiable, that something ingested can trigger this nervous system such that things like diarrhea occur immediately – it doesn’t have to work it’s way through the entire GI tract before causing reaction at the other end.
It would be quite possible that meditative activity interacts with the ENS, like, for instance, it’s well documented (e.g. experiments in the mid-20th-century at the Stanford Research Center and elsewhere) that “yogic” practices can develop conscious control in areas of the ANS (autonomic nervous system), which was previously thought to be out of range of conscious influence. (Science often exhibits a sort of naivite in presupposing that any thing not figured-out by its rules is not valid “knowledge”.)
btw: Back in those days (ca. 1970) I was involved in such research – wrote the first computer program converting brain wave data from scalp electrodes into a real-time aural feedback system, with which one could readily learn to invoke “alpha-wave” brain activity at will. (Maybe working with that helped me, decades later, in samadhi training?)
I suggest you take a careful look at this guided meditation, perhaps with advice from an advanced teacher of yoga or Qigong, and make sure it is not harmful to you. (from a position of been there/done that/still trying to recover two months later)
The farting got so bad at the retreat I went to, they had to open all the doors and windows and let the dhamma hall air out for a while. It was so distracting and pretty gross too.
Too many people eating beans? 
Tell me about it!!! I have known for decades that the 8 hour rule is a furphy. I suspect that the “something ingested” may be either/both emotional or material. In my own case the range of possible triggers remains a mystery.
Nice practical area to work on with cultivating mindful observation?