That rumble in your belly is a normal occurrence, but certainly a little embarrassing in a quiet room of people. We instantly assume, “Gosh, they must be hungry”. This growl is also referred to as “peristaltic” or “bowel” noise. The food in the gastro-intestinal tract is moving through the small intestine and likes to make its presence known when these muscle contractions occur. Sort of like that loud person in the gym who grunts. On an empty stomach, this noise becomes louder. Sometimes our stomach roars right before a meal because we are hungry and sometimes the belly shouts when we are totally satiated. This is confusing when it comes to our hunger cues.
The growling isn’t really coming from your stomach. This noise is termed, “borborygmic”, which means rumbling in Greek. Sometimes if you haven’t eaten in a while, your stomach growls possibly because your blood sugar has dropped, and the body is signaling that it needs nutrients to recover. When we finally eat, the food makes that noise go away because the space has been filled. The air isn’t free to move around anymore. We have a lot of air in the stomach mainly due to swallowing. When we eat too fast we also take in more air. The reason mama told us to chew with our mouth closed was to not let so much air in. Our stomach also doesn’t like bad food, so that is why a meal of junk can make a person gassy. The mixture of air, food, and gas propels the growling sound.
The smooth muscle cells of the gut contract rhythmically which is called basal electric rhythm (BER). This contraction typically occurs at a rate of 3 to 12 times per minute. However, hormones and the autonomic nervous system can affect this timing. Contraction usually occurs with the presence of food but can also occur when the stomach has been empty for about 2 hours. The receptors of the smooth muscle wall sense the lack of food and generate migrating myoelectric complexes (MMCs). These are the hunger contractions which can last for 10 to 20 minutes and up to 2 hours until the next meal is eaten. Low blood sugar heightens the MMCs.
Your stomach growling doesn’t mean that you are necessarily hungry. You could just have too much air, gas, or are getting ready to have a bowel movement because the small intestine is digesting. The key is understanding that you are typically hungry when you blood sugar is low. Signs of this would be feeling tired, dizzy or lightheaded, or maybe feeling a little anxious. Check in with these feelings before automatically assuming you must be hungry if your stomach is growling. Have a glass or two of water to help see if merely digestion is occurring. Your gut has a mind of its own and if often referred to as our second brain. When you are anxious or nervous, it talks to you which may link to emotional eating. True hunger means your body needs to be refueled. Try eating every 3 hours to stabilize your blood sugar and home in on eating to fuel your body.
Borborygmi: What Is It, Causes, Treatment, and More | Osmosis
Hunger and malnutrition in the 21st century | The BMJ
Full article: Hunger and sustainability (tandfonline.com)
Dr. Megan Johnson McCullough owns a fitness studio in Oceanside CA called Every BODY’s Fit. She has a Doctorate in Health and Human Performance, M.A. in Physical Education & Health Science, and she’s an NASM Master Trainer & Instructor. She’s also a professional natural bodybuilder, fitness model, Wellness Coach, and AFAA Group Exercise Instructor. She has 6 books on Amazon too,.
