What is the Urea Cycle?
The Urea cycle is a series of chemical reactions that take place inside your body when you digest food. The breakdown of protein into amino acids and other building blocks takes place in the liver. These building blocks are then absorbed into the bloodstream where they help build up muscles, bones, organs and other tissues.
When these processes go wrong, it leads to various diseases such as cancer or heart disease. It also can lead to liver problems, and can even shorten life span. The right kind of foods and a good diet can prevent or even cure these diseases.
What are the different steps?
In the early 1920’s, a Swedish physician, Dr. Bertil Fox first identified this cycle. He noticed that when he took care of patients with certain diseases, many of them had histories of eating a lot of meat. This lead him to believe that something in meat must be affecting them. This cycle was later identified by Annette Hirsch, a physician who worked with Dr. Bert Fox.
It goes like this: urea, a byproduct of the breakdown of amino acids in your body, is excreted from your body in your urine. When you eat protein, the body breaks down the amino acids into elementary chemicals such as carbon dioxide and water. The chemicals then get used to create energy. As a byproduct, the chemicals also produce urea.
This is when the cycle starts.
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There are two types of amino acids: essential and non-essential. Most of your body is made up of essential amino acids, meaning you can’t make them from other chemicals in your body, you need them from the food you eat. These include:
Non-essential amino acids can be made from other chemicals in your body, so you don’t need to worry about them. These include:
What happens when you stop this process?
When you stop this process in the middle, it can be very dangerous. When you stop digesting a big meal, for example, your blood sugar can fall very low. If this occurs, your body tries to get it back up by creating still more glucose in your liver. Glucose is a type of sugar your body uses for energy, but it can’t do this when there are no carbohydrates in your diet. Large amounts of liver glycogen is broken down into glucose, which causes a dramatic increase in the blood sugar level. This can cause you to feel dizzy, weak, tired and feverish . If this occurs it is important to keep moving and shake it off, as standing still while the liver breaks down glycogen can speed up the process and lead to death.
The liver can also start to break down fat into its component parts, called fatty acids and glycerol. These are then used to create energy in other chemical reactions in the body. This process is called ketosis and can be healthy if your diet consists mainly of fat. If you severely limit the amount of carbohydrates in your diet, your body will automatically start to break down fat into this usable form.
This process can be dangerous for people with diseases that break down fat in the body.
What happens to people with a slow-acting poison?
The body has several methods of excreting certain types of poisons. The two main ones are through the bowels and sweat glands.
When a poison is excreted through the bowels, the body takes it and breaks it down into less harmful substances. This can take anywhere from several days to several weeks. Even once the toxin has been broken down, it may still take time before all of it has left the body. Depending on the poison, it may also still leave behind a small amount of it.
In some cases, it can take a serious amount of time and the poison will still harm the body.
Poisons excreted through the bowels are divided into two main groups:
In general, the poisons that are broken down the most are the ones that can be dangerous if ingested or inhaled, like the poisons from the plant foxglove or the nicotine in cigarettes. On the other hand, the most dangerous group of poisons to excrete through the bowels are those that can be dangerous even after they have been broken down. This is because the toxins that do not get excreted can build up in the body and cause problems. These can include the alcohol and medicines that are broken down by the liver and passed through the bile, the heavy metals like lead and mercury that build up in the body over time, and some industrial toxins that are slow to break down.
The rate at which a poison is excreted through the skin is different from the way it is excreted through the bowels. While the former can be controlled by changing how much a person sweats, the latter is strictly regulated and will only occur at the rate that the body can eliminate the poison. This means it is possible to speed up the process by sweating, but it is extremely dangerous to accelerate the skin-drying process. The risk of kidney and brain damage is high.
The skin has a large amount of sweat glands, which are small pores just under the surface of the skin that can release sweat if stimulated. This sweat can carry the poisons over to the outside of the body.
The poisons that are broken down through the skin can either be excreted through the pores in the skin or they can be transferred to another person. This process is known as transference. Some poisons can be transferred through Exchange of Sweat, when sweat in one person transfers to the pores of another person. Other poisons are able to be absorbed into the skin.
In these cases, they can then move through the body through the circulatory system.
Some poisons can be carried on the wind. This is common with industrial toxicants, like some gases and some solvents, as well as with some pesticides.
- Regulation of enzymes of the urea cycle and arginine metabolism (SM Morris Jr – Annual review of nutrition, 2002 – annualreviews.org)
- SIRT5 Deacetylates carbamoyl phosphate synthetase 1 and regulates the urea cycle (T Nakagawa, DJ Lomb, MC Haigis, L Guarente – Cell, 2009 – Elsevier)
- Adaptive characteristics of urea cycle enzymes in the rat. (RT Schimke – Journal of Biological Chemistry, 1962 – cabdirect.org)
- The incidence of urea cycle disorders (…, Members of the Urea Cycle Disorders … – Molecular genetics and …, 2013 – Elsevier)