Swapna Krishna

Oct 12th 2022

How Does the Body Break Down Food?


You likely think about what to eat every single day. After all, it’s one of the basic requirements you need to survive. Yet you may not ruminate on what happens to your food after you eat it. How does the body break down food anyway? How do you process what you eat and how does your body use the nutrients? How long does it take?

This article will examine the ins and outs (pun intended) of food digestion, including how digestion happens, what occurs within your body when you eat, how your system processes different ingredients and digestion time.

How Is Food Digested?

The digestive system is larger than you think. According to Johns Hopkins, it consists of “the mouth, esophagus, stomach, pancreas, liver, gallbladder, small intestine, large intestine and anus.” All of these organs work together to ensure you can digest the food you eat.

The process of digestion starts before you take a single bite — your sense of smell triggers extra saliva, which has enzymes that start the long process. The pancreas produces those enzymes, and after you swallow food, those enzymes mix with other digestive juices in your stomach. This watery mixture then moves to your small intestine, where the nutrients are extracted, and whatever is left moves through your large intestine and is excreted through the anus.

Do Different Foods Digest at Different Rates?

This description of digestion seems quite simple, but in reality it’s quite complicated. The process of digestion takes, on average, several hours. You know that recommendation to eat protein to feel full? That’s because protein, along with fat, takes longer to digest than carbohydrates.

The type of food you’re eating has a huge effect on the amount of time it takes to digest. Liquids are the fastest — water leaves the stomach in just 10 minutes. More complex liquids take up to an hour, while carbs like pasta and rice can take just 30 minutes. Add protein into the mix? You’re looking at two to four hours, possibly even longer. Proteins take longer to digest because breaking them down into their component amino acids takes more time than digesting carbs or other foods.

What Impacts Digestion Time? Is Faster Better?

It’s not just the kind of food you’re eating that impacts digestion time. Other factors include what time of day you eat, gender (women digest more slowly than men), and age (the aging process slows down digestion, which is part of the reason elderly people have to keep an eye on their digestive health).

Your body’s natural circadian rhythms are also tied to your digestive system — eating when your body expects you to eat means that digestion happens faster. If you decide to eat a lot at 1 a.m., your digestive system likely isn’t expecting it, and will process that food more slowly. Digestion is a very individualized process that varies from person to person; it’s even possible that your body type has a significant impact on how you digest food.

The rate of digestion could also provide health benefits. Generally speaking, the faster the digestion time, the better. Studies have shown that slower transit time through your digestive system is linked to increased harmful bacteria. Conventional thinking is that the more gut bacteria you have, the healthier your digestive system, but it turns out that isn’t actually always the case. Longer digestion time and food sitting too long within your large intestine can produce harmful bacteria.

If you want to prioritize your digestive health and pay attention to how your body breaks down food, eat a balanced diet (with lean proteins and fiber) and stay hydrated. Eat on a regular schedule, exercise regularly (digestion requires energy, after all!), sleep well, and keep stress and anxiety levels low.

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