Whether it happens after a big meal or in our sleep, in the privacy of our bathrooms or in a muted (thankfully) yoga Zoom class — it happens to everyone. 5-15 times a day, in fact! Gas is normal — usually. We asked Hilma scientific advisor Paul Grewal, MD, an internal medicine physician and co-author of the New York Times best-selling book Genius Foods, to tell us what we should know about gas, and what it can tell you about your body.
There are two main types of gas
"The first is stomach gas, which is mainly caused by swallowing air when eating or drinking. Most of this gas is released by burping," Dr. Grewal explains. "The second type of gas, formed in your intestines, is caused by the bacteria in your colon digesting complex carbohydrates that your small intestine wasn’t able to process. The bacteria digest these undigested carbohydrates in a process called fermentation, which forms gases (mainly hydrogen, methane, and carbon dioxide) as byproducts."
What's on your plate?
Fiber and starch are complex carbohydrates that are primarily digested by the bacteria in your colon, Dr. Grewal explains, so foods like beans, fruits, vegetables, and whole grains will make you more gassy. But you don't have to cut down on favorite foods just because they produce more gas. "Occasionally, reducing meal frequency or short fasts to give the digestive system some time to rest and recover can prevent overfeeding the bacteria that cause these gases," Dr. Grewal says.
If you're passing gas 20 times, or more, a day, then you might have what's considered “flatulence”, which can be caused by digestive disorders. Watch out for other symptoms too, like pain and excessive bloating. "If your gas or any pain associated with bloating begin to interfere with daily life, it may be time to see a doctor who can evaluate you for more serious conditions," Dr. Grewal advises.
The smell test
Let's just be real here — sometimes gas causes us (and any other poor souls in the room with us) to wonder what the heck we ate. And it could in fact be something you ate — simply eating high-fiber foods (which are very healthy!) can cause foul-smelling farts. But so can eating something you have an intolerance to, so again, don't shy away from checking with your doc if you think something is wrong. Being constipated, taking certain medications, including antibiotics, and bacterial buildups in your digestive tract can also contribute.
Yes, your gas really is worse during your period
You’re not imagining it. Not only does water retention make us feel bloated during our periods, but our progesterone and estrogen hormones also create more gas in our small intestines. Your body is also busy releasing fatty acids called prostaglandins, which cause your uterus to contract and shed its lining. When you release too many prostaglandins, they head over to hang out in your bowels, causing contractions — and therefore gas. As for that clear-the-room smell? Changes in your gut bacteria caused by both hormones and hormonal changes in diet can increase sulfur in your gut, creating the “rotten egg” odor.
You can address your burps too
Remember, gas doesn't just come out one end. Since burps start in the stomach, eating too quickly or talking while chewing may cause you to swallow more air and burp more, Dr. Grewal says. "To reduce burping during or after eating, your main focus should be on swallowing less air. Eating more slowly, not washing down food with liquids, avoiding hot beverages, and not drinking through straws will all help reduce the amount of gas trapped in your stomach during meals."
And keep in mind, as Dr. Grewal says, "generating and passing gas is a normal part of healthy digestion." So next time you accidentally let one go in public, you can thank your body for the overeager reminder that it's just doing its best.