Ever think about what happens to the food you eat or the liquids you drink? Have you ever been curious to know how your body handles that deep dish pepperoni and sausage pizza or the triple chocolate chip cookie dough ice cream? Do you know what it takes for your stomach to process all those soft drinks, energy bars, smoothies, pasta bowls, and fried rice? That process is called "Digestion," and it miraculously transforms all the junk food or the healthy meals that you consume every day of your life into small particles that your internal organs and bodily systems can handle. As long as what you eat is not poisonous, toxic, contaminated, or otherwise fatal, the human body has the capability to take all that you eat or drink and get rid of it in a way that keeps you functioning without getting drastically ill--most of the time.
When you eat foods—such as bread, meat, and vegetables—they are not in a form that the body can use as nourishment. Food and drink must be changed into smaller molecules of nutrients before they can be absorbed into the blood and carried to cells throughout the body, according to the National Institutes for Health (NIH). Digestion is the process by which food and drink are broken down into their smallest parts so the body can use them to build and nourish cells and to provide energy. Digestion involves mixing food with digestive juices, moving it through the digestive tract, and breaking down large molecules of food into smaller molecules. Digestion begins in the mouth, when you chew and swallow, and is completed in the small intestine.
According to the NIH, the digestive system is made up of the digestive tract—a series of hollow organs joined in a long, twisting tube from the mouth to the anus—and other organs that help the body break down and absorb food. Organs that make up the digestive tract are the mouth, esophagus, stomach, small intestine, large intestine—also called the colon—rectum, and anus. Inside these hollow organs is a lining called the mucosa. In the mouth, stomach, and small intestine, the mucosa contains tiny glands that produce juices to help digest food. The digestive tract also contains a layer of smooth muscle that helps break down food and move it along the tract. Two “solid” digestive organs, the liver and the pancreas, produce digestive juices that reach the intestine through small tubes called ducts. The gallbladder stores the liver’s digestive juices until they are needed in the intestine. Parts of the nervous and circulatory systems also play major roles in the digestive system.
The first step in the digestive process happens before you even taste food, according to KidsHealth.org. Just by smelling that homemade apple pie or thinking about how delicious that ripe tomato is going to be, you start salivating — and the digestive process begins in preparation for that first bite. Food is your fuel, and its nutrients give your bodies' cells the energy and substances they need to operate. But before food can do that, it must be digested into small pieces the body can absorb and use. The smooth muscle in the walls of the tube-shaped digestive organs rhythmically and efficiently moves the food through the system, where it is broken down into tiny absorbable atoms and molecules. During the process of absorption, nutrients that come from the food (including carbohydrates, proteins, fats, vitamins, and minerals) pass through channels in the intestinal wall and into the bloodstream. The blood works to distribute these nutrients to the rest of the body. The waste parts of food that the body can't use are passed out of the body as feces. Every morsel of food you eat has to be broken down into nutrients that can be absorbed by the body, which is why it takes hours to fully digest food. In humans, protein must be broken down into amino acids, starches into simple sugars, and fats into fatty acids and glycerol. The water in your food and drink is also absorbed into the bloodstream to provide the body with the fluid it needs.
According to the NIH, the large, hollow organs of the digestive tract contain a layer of muscle that enables their walls to move. The movement of organ walls can propel food and liquid through the system and also can mix the contents within each organ. Food moves from one organ to the next through muscle action called peristalsis. Peristalsis looks like an ocean wave traveling through the muscle. The muscle of the organ contracts to create a narrowing and then propels the narrowed portion slowly down the length of the organ. These waves of narrowing push the food and fluid in front of them through each hollow organ. The first major muscle movement occurs when food or liquid is swallowed. Although you are able to start swallowing by choice, once the swallow begins, it becomes involuntary and proceeds under the control of the nerves. Swallowed food is pushed into the esophagus, which connects the throat above with the stomach below. At the junction of the esophagus and stomach, there is a ringlike muscle, called the lower esophageal sphincter, closing the passage between the two organs. As food approaches the closed sphincter, the sphincter relaxes and allows the food to pass through to the stomach.
The stomach has three mechanical tasks, according to the NIH. First, it stores the swallowed food and liquid. To do this, the muscle of the upper part of the stomach relaxes to accept large volumes of swallowed material. The second job is to mix up the food, liquid, and digestive juice produced by the stomach. The lower part of the stomach mixes these materials by its muscle action. The third task of the stomach is to empty its contents slowly into the small intestine.
Now, several factors affect emptying of the stomach, including the kind of food and the degree of muscle action of the emptying stomach and the small intestine, according to the NIH. For example, carbohydrates, spend the least amount of time in the stomach, while protein stays in the stomach longer, and fats the longest. As the food dissolves into the juices from the pancreas, liver, and intestine, the contents of the intestine are mixed and pushed forward to allow further digestion. Finally, the digested nutrients are absorbed through the intestinal walls and transported throughout the body. The waste products of this process include undigested parts of the food, known as fiber, and older cells that have been shed from the mucosa. These materials are pushed into the colon, where they remain until the feces are expelled by a bowel movement.
Much more information about the technicality of digestion can be found at this website: http://digestive.niddk.nih.gov/ddiseases/pubs/yrdd/.
According to NaturalNews.com, many people experience gas and bloating after eating. Gas can accumulate in the stomach or the intestines, causing pain, rumbling and indigestion. Gas is a product of incomplete digestion and an indication that food is fermenting in the gut, instead of being digested properly and assimilated into the body as nutrients. As people age, their levels of digestive enzymes decrease. Many individuals find they need to add digestive supplements to meals. Digestive enzymes come in many forms. Certain foods contain natural digestive aids, such as pineapple and papaya. Adding a few bites of these foods to every meal can aid digestion. Also as the body ages, the amount of hydrochloric acid secreted to aid in digestion decreases. This leads to a condition known as hypochlorhydria. Hypochlorhydria begins as a gut deficiency and is one of the leading causes of gas and indigestion, and it can lead to many diseases and chronic inflammation. Without this important stomach acid, protein cannot be digested and many nutrients cannot be absorbed. In addition, acid from the stomach is a signal to the pancreas to perform its function, so hypochlorhydia can lead to problems in the pancreas as well. Diseases associated with low stomach acid include asthma, lupus, anemia, psoriasis, arthritis, ulcers, and many more. Indicators of low stomach acid can be simple gas and bloating, or more complex conditions, such as food allergies, constipation, anemia, and nausea. Food allergies may also cause gas. Many people are allergic to wheat and/or dairy. Allergy tests can confirm this but a simpler method is to remove suspected foods from the diet. If digestion returns to normal, eliminate the allergic foods for a few months and then begin to slowly reintroduce them. Food sensitivities can be healed in this manner, by removing the irritating food for a few months. True allergies may not respond to this technique.
You should also provide for healthy intestinal transit, according to WHFoods.com. The movement of the food, or chyme, through the digestive tract is very important. Healthy intestinal transit is supported, in part, by the short-chain fatty acids produced by fermentation of prebiotic fibers in the colon. Fiber, in general, supports overall transit of the chyme and healthy elimination. Some fibers, like those found in rye, wheat and flax, also can bind to environmental toxins, such as pesticides, and carry them through the digestive tract for direct elimination, decreasing the amount that is absorbed into your body.
Also, according to WHFoods.com, you should learn how to deal with stress effectively. Research has shown that the intestine responds negatively to stress, during which the intestinal lining becomes leaky, absorption is less effective, and your body is unable to selectively take up the nutrients it needs. The reasons for these effects of stress on the intestinal tract are not entirely known, however many neurotransmitters (brain-produced signaling molecules) are found surrounding the intestinal tract. Furthermore, neurotransmitter receptors, which can bind and respond to these signaling molecules, are located along the intestinal tract. Therefore, it is known that brain signaling molecules can affect the intestinal tract. Foods with a calming effect include herb teas, like chamomile. Alcohol, caffeine, and refined carbohydrates, like table sugar, should be avoided. Eating meals at regular times and in a relaxed environment can also help decrease stress. A host of more valuable material concerning digestion can also be found at this website: http://www.whfoods.com/genpage.php?tname=faq&dbid=16. Additionally, a great site for kids to understand the digestive process can be found at: http://kidshealth.org/parent/general/body_basics/digestive.html.
According to the Mayo Clinic, stomach noise — such as rumbling, gurgling and growling — typically is due to normal digestion. Stomach growling can occur when you're hungry. But it can also occur after eating or between meals when food is passing through your intestines. Hunger and appetite are controlled by a complex system of hormone-like substances primarily made by your digestive system. When you haven't eaten for a while, these substances are released and cause a part of your brain called the hypothalamus to "switch on" your desire to eat. A message is then sent to your stomach and intestines. This triggers muscle contractions and the release of acids and other digestive fluids — which causes the rumbling, grumbling sounds you hear — as your body prepares for you to eat. The thought, sight or smell of food also can trigger this response. Sometimes excessive stomach noise can be a symptom of an underlying gastrointestinal disorder, such as irritable bowel syndrome. But in such cases, stomach noise usually is accompanied by other signs and symptoms such as bloating, cramping, diarrhea or excess gas.
Digestion time varies depending on the individual, according to the Mayo Clinic. For healthy adults, it's usually between 24 and 72 hours. After you eat, it takes about six to eight hours for food to pass through your stomach and small intestine. Food then enters your large intestine (colon) for further digestion and absorption of water. Elimination of undigested food residue through the large intestine usually begins after 24 hours. Complete elimination from the body may take several days. The digestive system is a pretty important part of your body, according to KidsHealth.org, and without it, you couldn't get the nutrients you need to stay healthy. The next time you sit down to lunch, you'll know where your food goes — from start to finish!
Until next time. Let me know what you think.