It is one of the most googled diving questions, and there is no shame in asking it. The short answer is yes, you can, but the physics of depth make it less straightforward than on land. Nothing about it is dangerous, and understanding why is a fun little lesson in how pressure changes gas inside your body when you dive.
Yes, but pressure changes things
Intestinal gas is real gas, so it can leave your body underwater just like at the surface. The difference is that at depth the surrounding water pressure compresses that gas, so a bubble that would feel large on land is squeezed much smaller down below.
As you ascend, the same gas expands again according to Boyle's law. So a modest release at 18 meters becomes noticeably bigger as you rise, which is more curiosity than concern.
Will your wetsuit trap it?
A common myth says a fart could inflate your wetsuit or send you rocketing to the surface. It will not. The volume of gas involved is tiny compared to your buoyancy control device, and it vents harmlessly into the water.
You may feel or hear a muffled bubble, and that is all. Your buoyancy stays firmly in your own hands through your BCD and breathing.
A tip for comfort
If you tend to feel gassy, avoid a heavy, carbonated or very fibrous meal right before diving. Trapped gas expanding on ascent can cause mild abdominal discomfort, so a lighter meal keeps you comfortable.
This is the same reason we ascend slowly: every gas space in your body, from your ears to your gut, needs a moment to equalize as the pressure drops.
Marine animals do it too
If it makes you feel better, you are in good company underwater. Several fish release gas as part of digestion or buoyancy control, and some, such as herring, are even thought to communicate with tiny bubble sounds.
So a stray bubble from a diver is just another small, natural part of the reef soundtrack. Nobody down there is judging you, and the fish have heard it all before.
Come laugh about it in Isla Fuerte
Diving is full of small, funny discoveries like this, and there is no better classroom than the warm 27 to 29°C water around Isla Fuerte, one of the best preserved reefs of the continental Colombian Caribbean. In our small groups, no question is too silly to ask.
If you have always been curious about what your body really does underwater, come try a Discover Scuba session with us. Browse our courses and dives or plan a longer stay through our lodging.
Important
This is general educational information, not medical advice. Always complete the medical questionnaire honestly, dive within your training and, if in doubt, consult a diving physician or contact DAN (Divers Alert Network). In an emergency in Colombia, the nearest hyperbaric chamber is in Coveñas.
