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Your stomach growling is caused by your digestive system doing what it's supposed to do: mixing food, fluids, and gastric juices and pushing them through the intestinal tract. The rumbling occurs when the walls of your gastrointestinal tract contracts and relaxes to squeeze everything through the intestines. Even with a proper diet, growling is bound to happen sometimes and is no reason to be embarrassed. When you eat too much food, it will put your digestive system into overdrive. The growling can occur more often when this happens, because there is more to move through the intestines. When your stomach has been empty for two hours, the growling sounds louder. This is because there is little or nothing in the stomach to absorb or muffle the noise. When you go hours without eating, your body releases hormones that let the brain know it's time to clear anything left in the stomach to make room for whatever food is to come. Have small, healthy snacks with you at all times. Constantly hydrate yourself with liquids. Use water, juice, tea, etc. Certain carbs are resistant to digestion. Don't avoid carbs completely because they help supply you with energy and play a main role in the health of your digestive tract. Simply eat them in moderation to keep your stomach healthy but less likely to growl. Resistant starch: potatoes or pasta that has been cooled after cooking, sourdough bread, and unripe fruit. Insoluble fiber: whole-wheat flour, wheat bran, cabbage, lettuce, and bell peppers Sugar: apples, pears, and broccoli Remember that growling can happen both when you've just eaten and when you haven't eaten in a while. To avoid over-eating and excessive stomach growling, know when you're actually hungry. Learning the timing scheme your normal eating regimen is the best way to keep track and avoid mindless eating. People who swallow a lot of air usually experience more stomach growling than others. If you eat too fast or talk a lot while eating, you are likely swallowing a lot of air. Eat more slowly to avoid this.
Understand what is normal. Try not to eat large meals before class. Avoid an empty stomach. Limit indigestible foods. Know your hunger cues. Eat slowly and chew properly.