Metabolism


Unit Overview: Our Metabolism is a collection of chemical reactions that takes place in the body's cells. The metabolism converts the fuel in the food we eat into the energy needed to power everything we do, from moving to thinking to growing. Specific proteins in the body control the chemical reactions of metabolism, and each chemical reaction is coordinated with other body functions. Thousands of metabolic reactions happen at the same time — all regulated by the body — to keep our cells healthy and working. The metabolism is a constant process that begins when we're conceived and ends when we die. It is a vital process for all life forms. If metabolism stops, all living things die.

After food is eaten, enzymes in the digestive system break proteins down into amino acids, fats into fatty acids, and carbohydrates into glucose. In addition to glucose, both amino acids and fatty acids can be used as energy sources by the body when needed. These compounds are absorbed into the blood, which transports them to the cells. After they enter the cells, other enzymes act to speed up or regulate the chemical reactions involved with "metabolizing" these compounds. During these processes, the energy from these compounds can be released for use by the body or stored in body tissues, especially the liver, muscles, and body fat.

The metabolism that involves two kinds of process that go on at the same time — the building up of body tissues and energy stores and the breaking down of body tissues and energy stores to generate more fuel for body functions:
  • Anabolism or constructive metabolism, is the process for building and storing: It supports the growth of new cells, the maintenance of body tissues, and the storage of energy for use in the future. During anabolism, small molecules are changed into larger, more complex molecules of carbohydrate, protein, and fat.
  • Catabolism or destructive metabolism, is the process that produces the energy required for all activity in the cells. In this process, cells break down large molecules (mostly Carbohydrates and fats) to release energy. This energy release provides fuel for anabolism, heats the body, and enables the muscles to contract and the body to move. As complex chemical units are broken down into more simple substances, the waste products released in the process of catabolism are removed from the body through the skin, kidneys, lungs, and intestines.


1. Nutritional Requirements

Food provides molecules used in cell respiration for energy.
  • The metabolic rate is influenced by physical activity, temperature and eating; the basal metabolic rate is measured as the rate of oxygen consumption when such influences are standardized and minimal.
  • The energy provided by food and the energy consumed by the body are measured in units of kilocalories.
    • A kilocalorie is the energy required to raise the temperature of 1000 g of water from 14°C to 15°C. A kilocalorie is the unit of measurement used to express the energy content of food.
  • When the caloric intake is greater than the energy expenditure over a period of time, the excess calories are stored primarily as fat.

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Vitamins and elements serve primarily as cofactors and coenzymes.The fat-soluble vitamins A and D have specific functions but share similar mechanisms of action, activating nuclear receptors and regulating genetic expression.
  • Vitamins are divided into those that are fat-soluble (A, D, E, and K) and those that are water-soluble Vitamins (B1,B2, B3, B6,B12, C, pantothenic acid, biotin, folic acid ) .
  • Many water-soluble vitamins are needed for the activity of the enzymes involved in cell respiration.

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Use the table above to get into the right category and age group.

Infants 0.0-0.05
0.5-1

Children 1-3
4-6
7-10
Males 11-14
15-18
19-24
25-50
51+
Females 11-14
15-18
19-24
25-50
51+

Pregnant
Lactating 1st 6 months
2nd 6 months


Minerals (Elements) are needed as cofactors for a wide variety of critical functions.

-Those needed in large amounts everyday: Sodium, potassium, magnesium, calcium, phosphorus, and chlorine.

-Those trace elements that are essential to our body's function: iron, zinc, magnanese, flourine, copper, molybdenum, chromium, and selenium.

Free Radicals and Antioxidants

Normally, bonds don't split in a way that leaves a molecule with an odd, unpaired electron. But when weak bonds split, free radicals are formed. Free radicals are very unstable and react quickly with other compounds, trying to capture the needed electron to gain stability. Generally, free radicals attack the nearest stable molecule, "stealing" its electron. When the "attacked" molecule loses its electron, it becomes a free radical itself, beginning a chain reaction. Once the process is started, it can cascade, finally resulting in the disruption of a living cell.

Some free radicals arise normally during metabolism. Sometimes the body's immune system's cells purposefully create them to neutralize viruses and bacteria. However, environmental factors such as pollution, radiation, cigarette smoke and herbicides can also spawn free radicals.
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Normally, the body can handle free radicals, but if antioxidants are unavailable, or if the free-radical production becomes excessive, damage can occur. Of particular importance is that free radical damage accumulates with age.

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The vitamins C and E, are thought to protect the body against the destructive effects of free radicals. Antioxidants neutralize free radicals by donating one of their own electrons, ending the electron-"stealing" reaction. The antioxidant nutrients themselves don't become free radicals by donating an electron because they are stable in either form and act as scavengers, helping to prevent cell and tissue damage that could lead to cellular damage and disease.

  • Vitamin E - The most abundant fat-soluble antioxidant in the body. One of the most efficient chain-breaking antioxidants available. Primary defender against oxidation. Primary defender against lipid peroxidation (creation of unstable molecules containing more oxygen than is usual) (Reactive oxygen species- ROS).

  • Vitamin C - The most abundant water-soluble antioxidant in the body. Acts primarily in cellular fluid. Of particular note in combating free-radical formation caused by pollution and cigarette smoke. Also helps return vitamin E to its active form.


Antioxidants help keep ROS in balance

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2. Diabetes Mellitus and Hypoglycemia 19.4
Diabetes mellitus is when glucose over flows into the urine because the glucose concentration is too high. Then this happens the person has hyperglycemia. It is a result of a dysfunction in the secretion of insulin in the body. There are two different types of diabetes: type 1 and type 2. Diabetes in itself is a major cause for kidney failure, blindness, limb amputation, heart disease, and stroke.
In type one very little insulin is secreted if any at all because the beta cells are being destroyed by T lymphocytes. It is an autoimmune disease, associated with genetics and environmental factors. It is required for the person to take injections in order to stay alive because without insulin, glucose does not have the ability to enter the adipose cells. If a person overdoses with insulin can result in a coma

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With type 2 you have too much insulin and can treat it by diet and exercise. People have low insulin resistance. Exercise can help because it increases insulin sensitivity. Type 2 in common in obese people because it lowers insulin sensitivity. Insulin sensitivity slows down the ability of insulin to stimulate muscle and take adipose out of the blood. It also slows down the ability for insulin to stop the liver from making more blood glucose. Type 2 is usually hereditary and slow to form. Since obesity decreases insulin sensitivity, if you gain a lot of weight you may experience symptoms that go along with diabetes 2 but if you lose weight you may be able to decease some of the symptoms. That is another reason why exercise is important with type 2 also it helps to improve the sensitivity of the skeletal muscle fibers to insulin, making it easier for the skeletal muscles to remove glucose from the blood. People with type 2 also usually have poor circulation, which can lead to gangrene and atherosclerosis. If you are prediabetic you can prevent yourself from receiving type 2 diabetes if you are willing to change your lifestyle. This includes: exercise, losing weight, intake of more fiber, reduce intake of total fat and saturated fat.

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3. Metabolic Regulation by Adrenal Hormones, Thyroxine, and Growth Hormone

Catabolism of carbohydrates and lipids is stimulated by epinepherine, cortisol, thyroxine, and growth hormone. Thyroxine and growth hormone promote protein synthesis, body growth, and proper development of the central nervous system.

Adrenal Hormones
The adrenal gland consists of two parts: adrenal medulla and adrenal cortex. These function as separate glands and secrete different hormones. They are also regulated by different control systems. The adrenal medulla secretes catecholamine hormones in response to the sympathetic nerve stimulation. The adrenal cortex secretes corticosteroid hormones. They are grouped into two functional categories: mineralocorticoids (such as aldosterone) and glucocorticoids (such as hydrocortisone).
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Metabolic Effects of Catecholamines - These effects are similar to those of glucagon. They stimulate glycogenolysis and the release of glucose from the liver and of fatty acids from adipose tissue. During fasting, these actions occur in response to glucagon. The latter effect provides circulating energy substrates in anticipation of the need for intense physical activity. Sympathetic nerves can stimulate B3-adrenergic receptors in brown adipose tissue. Brown fat is a specialized tissue that contains an uncoupling protein that dissociates electron transport from production of ATP.

Metabolic Effects of Glucocorticoids - In response to ACTH stimulation, Hydrocortisone and other glucocorticoids are secreted by the adrenal cortex. The secretion of ACTH from the anterior pituitary occurs as part of the general adaption syndrome in response to stress. Increased secretion of glucocorticoids during prolonged fasting or exercise supports the effects of increased glucagon and decreased insulin secretion from the pancreatic islets. Hydrocortisone promotes liposys and ketogenesis. It also stimulates the synthesis of hepatic enzymes that promote gluconeogenesis and protein breakdown in the muscles. This latter effect increases the blood levels of amino acids. This provides substrates needed by the liver for gluconeogenesis. The release of amino acids, glucose, fatty acids, and keton bodies into the blood in response to hydrocortisone helps compensate for a state of prolonged fasting or exercise.


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Metabolic effects of glucocorticoids


Thyroxine
In response to stimulation by thyroid-stimulating hormone from the anterior pituitary, the thyroid follicles secrete thyroxine (also called tetraiodothyronine). The thyroid also secretes smaller amounts of triiodothyronine in response to stimulation by thyroid-stimulating hormone. Almost all of the body's organs are targets of thyroxine action. Thyroxine is not the active form of the hormone within the target cells. It is a pre-hormone that must be converted to triiodothyronine within the target cells to be active. Thyroxine stimulates the rate of cell respiratoin in almost all the cells in the body. This is due to a lowering of cellular ATP concentrations. This is produced by the production of uncoupling proteins.

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How epinephrine and glucagon affect metabolism


1 - The hormone binds to its receptor and causes G-proteins to dissociate.
2 - The alpha subunit diffuses through the membrane to activate adenylate cyclase. This catalyzes the production of cAMP as a second messenger.
3 - The cAMP binds to and removes the regulatory subunit of protein kinase which activates this enzyme.
4- The activation and inactivation of defferent enzymes promots glycogenolysis in the liver and lipolyhsis in adipose tissue.

Growth Hormone

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Metabolic effects of growth hormone

The anterior pituitary secretes growth hormone (also called somatotropin) in larger amounts than any other of its hormones. The growth hormone stimulates growth in children and adolescents. The continued high secretion of growth hormone in adults implies that this mormone can have important metabolic effects even after the growing years are over.
Somatostatin inhibits the secretion of growth hormone. It is produced by the hypothalamus and secreted into the hypothalamo-hypophyseal portal system. Growth hormone is also stimulated by a growth hormone-releasing hormone. This hormone is unique among the anterior pituitary hormones because its secretion is controlled by both a releasing and inhibiting hormone from the hypothalamus. The secretion of growth hormone follows a circadian pattern. This means that it increases during sleep and decreasing during periods of wakefulness. Growth hormone secretion is stimulated by an increase in plasma concentration of amino acids and by a decrease in the plasma glucose concentration. The secretion is also increased during prolonged fasting, when plasma glucose is low and plasma amino acid concentration is raised by the breakdown of muscle protein.
Growth hormone has both anabolic and catabolic effects. It promotes protein synthesis and stimulates the catabolism of fat and the release of fatty acids from adipose tissue during periods of fasting. Growth hormone will stimulate the cellular uptake of amino acids and protein synthesis in many organs of the body.




For a better understanding of the Metabolism please watch these videos Lesson 1, 2, 3

Essential Questions:

1) Find a product that says that it will boost your metabolism. Research the physiology behind how it boosts a persons metabolism. Summarize what you learned in your research.-Make sure to include the product name, the ingredient(s) that they claim increases metabolism, and then the physiology of how the ingredient increases metabolism.

Triple Complex Slimmer's Assist
Homeopathic remedy improves sluggish digestion, boosts metabolism & increases weight loss


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Triple Complex Slimmer's Assist is a combination of three biochemic cellular–supporting homeopathic tissue salts and may be taken at the first signs of obesity, weight gain, or sluggish metabolism or digestion for effective help.
Triple Complex Slimmer’s Assist is taken internally and improves weight loss by ensuring the digestive system and metabolism are functioning effectively. Presented in small tablet form, Slimmer’s Assist is easy to ingest and hassle–free with no artificial colors or
preservatives.
Due to its unique homeopathic formula, Triple Complex Slimmer’s Assist is safe for all ages, as well as during pregnancy and nursing. This product can be used to avoid excessive weight gain during pregnancy and also to lose the baby–weight after the baby has arrived.
All Native Remedies homeopathic products and biochemic tissue salts are manufactured in an FDA and GMP registered pharmaceutical facility under the supervision of qualified homeopaths and responsible pharmacists. Individual ingredients are listed in the Homeopathic Pharmacopoeia of the United States (HPUS).


What are the Ingredients?
Triple Complex Slimmer's Assist contains the following 100% homeopathic ingredients:
  • Kali phos (6X) is a natural nerve nutrient derived from potassium phosphate present in brain cells and nerve tissue.
  • Calc fluor (6X) is necessary where ample elasticity of the tissue is required. Calcium fluoride is needed for the brain, heart, lungs, kidneys, eyelids, bone cover, muscles and ligaments. The most important job it performs is to impact elasticity to tissue fibers and to maintain it, enabling the fibers to stretch and return to their original form.
  • Calc phos (6X) supports healthy digestion at a cellular level. It also assists in the formation of new blood cells and is present in connective tissue and digestive juices making it a vital component of the body's nutrition process from digestion and assimilation through to energy expenditure. An excellent general tonic for all ages!
Triple Complex Slimmer's Assist is registered with the Food and Drug Administration (FDA).
All Native Remedies homeopathic products and biochemic tissue salts are manufactured in an FDA and GMP registered pharmaceutical facility under the supervision of qualified homeopaths and responsible pharmacists. Individual ingredients are listed in the Homeopathic Pharmacopoeia of the United States (HPUS).
All products are free of gluten, artificial flavors, colorants and preservatives, and are suitable for use by lacto-vegetarians. In accordance with our Do No Harm policy, no animal testing is carried out whatsoever.

Information from Natural Remedies- The Natural choice 8

2) Why do crash diets not work on a physiology level?
  • When you do Crash Diets you aren't really loosing weight, what you are really loosing is water weight.This is because low-calorie diets cause the body to burn up excess glycogen, a type of glucose that absorbs excess fluid inside the body. Weight loss during crash diets doesn't continue for very long. Eventually, people will find themselves hitting a weight loss plateau, during which it will become more and more difficult to lose weight. The majority of crash dieters find that this weight loss plateau is followed by a period of weight gain. Many people who do crash diets end up putting back on all of the weight they lost and adding more on. This is known as the yo-yo diet effect: crash dieters find that their weight is constantly fluctuating with each diet that they go on. These types of diets starve your body and can mess the your metabolism, your body eventually clues in to the fact that it is receiving a very low number of calories. As a result, your body actually adjusts its metabolism, so that it burns fewer calories in order to perform all of its necessary bodily functions. This means that it takes fewer calories for you to gain weight, making it more and more likely that you will put on weight at the end of your diet. The body can maintain this decreased metabolism for a number of months, or even years, after a serious low-calorie diet.

  • Long-term crash dieting can result in serious nutritional deficiencies, as a result of eating a poor variety of foods. In particular, crash dieters are putting themselves at risk for: iron deficiency anemia, vitamin B12 deficiency, potassium and sodium deficiency.

  • Potassium and sodium deficiency is particularly dangerous. These electrolytes are used to ensure proper nerve and muscle function. They play a particularly important role in regulating the way the heart beats. If potassium and sodium levels become low enough, you could suffer from a heart attack.

  • Crash diets are extremely dangerous for vital organs, including the heart, kidneys, liver, and brain. In order to perform their daily functions, your vital organs rely on energy from your carbohydrate intake. During strict crash diets, carbohydrate and calorie intake is so low, that your organs cannot get enough energy from these sources. As a result, the organs begin to burn muscle tissue in order to get adequate amounts of energy to perform vital functions. If your calorie intake becomes low enough, the body will even begin to burn the muscle tissue that makes up your actual organs in order to provide your brain with sufficient energy to function. This can result in serious health problems, including: liver failure, kidney failure, heart attack, stroke

  • Long-term crash dieters frequently suffer from osteoporosis, causes the bones in the body to become extremely brittle. This is because fast crash diets severely limit their intake of calcium . As a result, calcium begins to leach out of the bones in the body, leaving them particularly fragile. Many crash dieters suffer broken bones, particularly hips and wrists, as a result of their osteoporosis.


Physiology Metabolism

How does this apply to PTA:
This applies to us because if we are giving a patient a massage this speeds up their metabolism so we need to make sure that afterward they take in lots of fluids. Because the liver plays an important role in nutrient absorption and metabolism, if anything happened to the liver we would have some kind of knowledge on how it might affect the metabolism, and how it will then effect our patient.






1. http://highered.mcgraw-hill.com/sites/0073378119/student_view0/chapter19/textbook_images.html
2. Fox, Stuart I. "Human Physiology." New York: McGraw-Hill, 2011. Print.
3. http://ykameelah.files.wordpress.com/2009/08/body-free-radicals3.png
4. http://ykameelah.wordpress.com/2009/08/13/free-radicals-antioxidants-in-disease-and-health/
5. http://markgubuan.com/wp-content/uploads/2010/04/antioxidant_activity.jpg
6. http://en.wikipedia.org/wiki/Metabolism
7. Goodman, Catherine Cavallaro., and Kenda S. Fuller. Pathology: Implications for the Physical Therapist. St. Louis, MO: Saunders/Elsevier, 2009.Print
8. http://www.nativeremedies.com/products/slimmersassist-healthy-weight-loss.html?ysmchn=GGL&ysmcpn=Google+Main&ysmgrp=Slimmers+Assist&ysmtac=PPC&ysmtrm=metabolism%20boosters#tabs