In general, food takes 24 to 72 hours to move through your digestive tract. The exact time depends on the amounts and types of foods you’ve eaten. The rate is also based on factors like your gender, metabolism, and whether you have any digestive issues that could slow down or speed up the process.
At first, food travels relatively quickly through your digestive system. Within six to eight hours, the food has moved its way through your stomach, small intestine, and large intestine.
Once in your large intestine, the partially digested contents of your meal can sit for more than a day while it’s broken down even more. A Mayo Clinic study found that the average time food spends in the large intestine varies by gender: 33 hours for men and 47 hours for women.
Your digestion rate is also based on what you’ve eaten. Meat and fish can take as long as two days to fully digest. The proteins and fats they contain are complex molecules that take longer for your body to pull apart.
By contrast, fruits and vegetables, which are high in fiber, move through your system in less than a day. In fact, these high-fiber foods help your digestive track run more efficiently in general.
The quickest to digest are processed, sugary junk foods like candy bars. Your body tears through them in a matter of hours, quickly leaving you hungry again.
Digestion is the process by which your body breaks down food and pulls out the nutrients your body needs to operate. Anything left is a waste product, which your body removes.
Your digestive system is made up of five main parts:
- small intestine
- large intestine
This is what happens when you digest food:
As you chew, glands in your mouth release saliva. This digestive liquid contains enzymes that break down the starches in your food. The result is a mushy mass called a bolus that’s easier to swallow.
When you swallow, the food moves down your esophagus — the pipe that connects your mouth to your stomach. A muscular gate called the lower esophageal sphincter opens to let the food move into your stomach.
Acids in your stomach break down the food even more. This produces a mushy mixture of gastric juices and partially digested food, called chyme. This mixture moves on to your small intestine.
In your small intestine, your pancreas and liver contribute their own digestive juices to the mix. Pancreatic juices break down carbohydrates, fats, and proteins. Bile from your liver dissolves fat. Vitamins, other nutrients, and water move through the walls of your small intestine into your bloodstream. The undigested part that remains moves on to your large intestine.
The large intestine absorbs any leftover nutrients from the food. The rest becomes solid waste, called stool.
Your rectum stores stool until you’re ready to have a bowel movement.
Certain conditions can disrupt digestion and leave you with some unpleasant side effects like heartburn, gas, constipation, or diarrhea. Here are a few:
- Acid reflux happens when the lower esophageal sphincter weakens. This allows acid to back up from your stomach into your esophagus. The main symptom is heartburn.
- Celiac disease involves your immune system attacking and damaging your intestines when you eat gluten.
- Constipation is fewer bowel movements than usual. When you do go, the stool is firm and hard to pass. Constipation causes symptoms like bloating and abdominal pain.
- Diverticulosis creates small, inflamed pouches in your intestines. Symptoms include abdominal pain, constipation, and bloating.
- Inflammatory bowel disease includes Crohn’s disease and ulcerative colitis. These conditions produce inflammation in your intestines.
- Irritable bowel syndrome causes uncomfortable symptoms such as gas, diarrhea, and constipation.
- Lactose intolerance means your body lacks the enzyme needed to break down the sugar in dairy products. When you eat dairy, you get symptoms like bloating, gas, and diarrhea.
To keep food moving smoothly through your digestive system and prevent issues like diarrhea and constipation, try these tips:
Eat more greens, fruit, and whole grains
Vegetables, fruits, and whole grains are all rich sources of fiber. Fiber helps food move through your digestive system more easily.
Limit red meat and processed foods
Meat takes longer for your digestive tract to break down. Plus, it produces chemicals that can damage your digestive tract.
Add probiotics to your diet
These beneficial bacteria help crowd out the harmful bugs in your digestive tract. You’ll find them in foods like yogurt and kefir, and in supplements.
Moving your body keeps your digestive tract moving, too. Taking a walk after meals can prevent gas and bloating. Exercise also keeps your weight in check, which lowers your risk for certain cancers and other diseases of the digestive system.
Get plenty of sleep
A lack of sleep is linked to obesity, which can contribute to problems with your digestive system.
Excess stress can worsen digestive conditions like heartburn. Stress-relieving techniques such as meditation and yoga can help calm your mind.
You might not think much about your digestive system on a daily basis. Yet you’ll know when it’s not working optimally by uncomfortable symptoms like gas, bloating, constipation, and diarrhea. Watch what you eat and stay active to keep your digestive tract moving smoothly and feel your best.