The 101 on Raw Food and Digestion
Recommended Dietary Intakes of Lipids. In most vertebrates , digestion is a multistage process in the digestive system, starting from ingestion of raw materials, most often other organisms. They also perform similar tasks. The nutrients can be returned to the soil for plant development or it can be used as feedstock for waste-to-energy applications. Tannin-binding proteins in saliva of deer and their absence in saliva of sheep and cattle. High doses of ginger can backfire; more than 2 to 4 grams per day can cause heartburn. Proteins are important nutrients that your body uses to build cellular structures that carry out vital functions.
The liver is a roughly triangular accessory organ of the digestive system located to the right of the stomach, just inferior to the diaphragm and superior to the small intestine. The liver weighs about 3 pounds and is the second largest organ in the body.
The liver has many different functions in the body, but the main function of the liver in digestion is the production of bile and its secretion into the small intestine. The gallbladder is a small, pear-shaped organ located just posterior to the liver.
The gallbladder is used to store and recycle excess bile from the small intestine so that it can be reused for the digestion of subsequent meals. The pancreas is a large gland located just inferior and posterior to the stomach. The pancreas secretes digestive enzymes into the small intestine to complete the chemical digestion of foods. The large intestine is a long, thick tube about 2.
It is located just inferior to the stomach and wraps around the superior and lateral border of the small intestine. The large intestine absorbs water and contains many symbiotic bacteria that aid in the breaking down of wastes to extract some small amounts of nutrients. Feces in the large intestine exit the body through the anal canal. The digestive system is responsible for taking whole foods and turning them into energy and nutrients to allow the body to function, grow, and repair itself.
The six primary processes of the digestive system include:. The first function of the digestive system is ingestion, or the intake of food. The mouth is responsible for this function, as it is the orifice through which all food enters the body. The mouth and stomach are also responsible for the storage of food as it is waiting to be digested. This storage capacity allows the body to eat only a few times each day and to ingest more food than it can process at one time. In the course of a day, the digestive system secretes around 7 liters of fluids.
These fluids include saliva, mucus, hydrochloric acid, enzymes, and bile. Saliva moistens dry food and contains salivary amylase, a digestive enzyme that begins the digestion of carbohydrates. Mucus serves as a protective barrier and lubricant inside of the GI tract. Hydrochloric acid helps to digest food chemically and protects the body by killing bacteria present in our food. Enzymes are like tiny biochemical machines that disassemble large macromolecules like proteins, carbohydrates, and lipids into their smaller components.
Finally, bile is used to emulsify large masses of lipids into tiny globules for easy digestion. Digestion is the process of turning large pieces of food into its component chemicals.
Mechanical digestion is the physical breakdown of large pieces of food into smaller pieces. This mode of digestion begins with the chewing of food by the teeth and is continued through the muscular mixing of food by the stomach and intestines. Bile produced by the liver is also used to mechanically break fats into smaller globules.
While food is being mechanically digested it is also being chemically digested as larger and more complex molecules are being broken down into smaller molecules that are easier to absorb. Chemical digestion begins in the mouth with salivary amylase in saliva splitting complex carbohydrates into simple carbohydrates. The enzymes and acid in the stomach continue chemical digestion, but the bulk of chemical digestion takes place in the small intestine thanks to the action of the pancreas.
The pancreas secretes an incredibly strong digestive cocktail known as pancreatic juice, which is capable of digesting lipids, carbohydrates, proteins and nucleic acids. By the time food has left the duodenum , it has been reduced to its chemical building blocks—fatty acids, amino acids, monosaccharides, and nucleotides.
Once food has been reduced to its building blocks, it is ready for the body to absorb. Absorption begins in the stomach with simple molecules like water and alcohol being absorbed directly into the bloodstream. Once the nutrients have been absorbed and the leftover liquid has passed through the small intestine, what is left of the food you ate is handed over to the large intestine, or colon. The colon is a 5- to 6-foot-long muscular tube that connects the cecum the first part of the large intestine to the rectum the last part of the large intestine.
It is made up of the cecum, the ascending right colon, the transverse across colon, the descending left colon, and the sigmoid colon so-called for its "S" shape; the Greek letter for S is called the sigma , which connects to the rectum. Stool, or waste left over from the digestive process, is passed through the colon by means of peristalsis contractions , first in a liquid state and ultimately in solid form as the water is removed from the stool.
A stool is stored in the sigmoid colon until a "mass movement" empties it into the rectum once or twice a day. It normally takes about 36 hours for stool to get through the colon.
The stool itself is mostly food debris and bacteria. These bacteria perform several useful functions, such as synthesizing various vitamins , processing waste products and food particles, and protecting against harmful bacteria.
When the descending colon becomes full of stool, or feces, it empties its contents into the rectum to begin the process of elimination. The rectum Latin for "straight" is an 8-inch chamber that connects the colon to the anus. It is the rectum's job to receive stool from the colon, to let you know there is stool to be evacuated, and to hold the stool until evacuation happens. When anything gas or stool comes into the rectum, sensors send a message to the brain.
The brain then decides if the rectal contents can be released or not. If they can, the sphincters muscles relax and the rectum contracts, expelling its contents. If the contents cannot be expelled, the sphincters contract and the rectum accommodates, so that the sensation temporarily goes away.
The anus is the last part of the digestive tract. It consists of the pelvic floor muscles and the two anal sphincters internal and external muscles. The lining of the upper anus is specialized to detect rectal contents. It lets us know whether the contents are liquid, gas, or solid.
The pelvic floor muscle creates an angle between the rectum and the anus that stops stool from coming out when it is not supposed to.
The anal sphincters provide fine control of stool. The internal sphincter keeps us from going to the bathroom when we are asleep, or otherwise unaware of the presence of stool. When we get an urge to go to the bathroom, we rely on our external sphincter to keep the stool in until we can get to the toilet. Continued Three organs play a pivotal role in helping the stomach and small intestine digest food: Pancreas Among other functions, the oblong pancreas secretes enzymes into the small intestine.
Liver The liver has many functions, but two of its main functions within the digestive system are to make and secrete bile, and to cleanse and purify the blood coming from the small intestine containing the nutrients just absorbed. Gallbladder The gallbladder is a pear-shaped reservoir that sits just under the liver and stores bile. Colon Large Intestine The colon is a 5- to 6-foot-long muscular tube that connects the cecum the first part of the large intestine to the rectum the last part of the large intestine.