Chapter 6 Proteins

Lacto vegetarian

Includes dairy products

Kidney stones

Increase in urinary calcium excretion associated with high protein diets has led to speculation that a high protein diet may increase the risk of kidney stones. Kidney stones are deposits of calcium and other substances in the kidneys and urinary tract. Higher concentrations of calcium and acid in urine increases the likelihood that the calcium will be deposited forming these stones. Studies suggest that diets that are rich in animal protein and low on fluid contribute to the formation of kidney stones

Source of protein

It's been suggested that the amount and source of protein in a diet affect calcium status and bone health. Adequate protein is essential for healthy bones but too much increases the amount of calcium lost in urine which has contributed to believe that high protein diets result in bone loss clinical studies don't support the idea that animal protein has a detrimental effect on bone health or that the bone is lost to provide the extra calcium lost in the urine

Negative nitrogen balance

Nitrogen intake is less than nitrogen output which indicates that more protein is being broken down that is being synthesized so body protein is decreasing this occurs due to injury or illness as well as when the diet is too low in protein and calories

Weightlifters

Often take the amino acid supplement arginine. Because this amino acid shares a transport system with lysine large doses can inhibit the absorption of Lysine upsetting the balance of amino acids in the body

Protein structure

Peptide bonds join the acid group of one amino acid to the amino group of another amino acid. Many amino acids bonded together constitute a polypeptide. A protein is made up of one or more polypeptide chains that are folded into three dimensional shapes. The order and chemical properties of the amino acids in a polypeptide determine its final shape because the folding of the chain occurs in response to the forces that attract or repel amino acids from one another or from water. The folded polypeptide chain May constitute the final protein or it may join with several other folded polypeptide chains

Incomplete dietary protein

Plant proteins are more difficult to digest and lower and one or more of the essential amino acids. They are there for generally referred to as incomplete dietary protein. Exceptions include quinoa and soy protein which are both high quality plant proteins

Proteins and regulating fluid balance

Prevent the level of activity and body fluids from deviating from the normal range. The chemical reactions of metabolism require specific level of acidity or pH to function properly period inside the body pH must be maintained at a relatively neutral level 2 allowed metabolic reactions to proceed normally and if it changes these reactions lower stop. Proteins both within the cells and in the body help prevent large changes in PH

Calcium

Can be supplemented with tofu, broccoli, kale, Collard and mustard greens, bok choy and legumes period products fortified with calcium such as a beverages Karma rice milk, almond milk, green products and orange juice

Gluten intolerance celiac disease

Cannot tolerate gluten a protein found in wheat, ride, and Beverly. An autoimmune disease in which gluten causes the body to attack the Villi in the small intestine resulting in symptoms such as diarrhea, abdominal bloating and cramps, weight loss, and anemia. Once thought to be a rare childhood disease but now it is known to affect more than two million people in the United States and manifest at any time in life

Omega-3 fatty acids

Canola oil flaxseed and flaxseed oil soybean oil walnuts sea vegetables which provide fatty acids can be used to synthesize EPA and DHA rich microalgae

Complementary proteins

Combining proteins that are limited in different amino acids can supply a complete mixture of essential amino acids. Vegetarian diets rely on this technique called protein complementation to meet protein needs. By eating plant proteins that have complementary amino acid patterns a person can meet their essential amino acid requirements without consuming animal proteins. Legumes are deficient in methionine and cytesine but high in lysine. Grains nuts and seeds are deficient in lysine but high in methionine and cytosine . When rice is eaten with beans in the meal provides enough of all of the amino acids needed by the body

Proteins that help us move

Protein actin and myosin are able to slide past each other to contract the muscles. A similar process causes contraction in the heart muscle and in the muscles of the digestive tract, blood vessels, and body cleanse

Lacto-ovo vegetarian

Excludes all animal flesh but it does include eggs and dairy products

Pescatarian

Excludes all animal flesh except fish

Semi-vegetarian

Excludes red meat but may include fish and poultry as well as dairy products and eggs

Protein recommendations

Express per unit of body weight because protein is needed to maintain and repair the body. The more a person weighs the more protein he or she needs for those purposes. Children need less protein but because new protein must be synthesized for growth to occur protein requirements per unit of body weight are much greater for infants and children than for adults. To calculate protein needs per day multiply weight in kilograms which is .45 X weight in pounds by the recommended amount for the individual's age

Protein intake and extreme stress has on the body

Extreme stress is on the body such as infections, fever, Burns, or surgery increase the amount of protein that is broken down. The extra amount needed for healing depends on the injury. A severe infection may increase the body's protein needs by about 30% and a serious burn can increase protein requirements by 200 - 400%

Structural proteins

Found in skin, hair, ligaments, and tendons and provide structure to individual cells where they are an integral part of the cell membrane, cytosol, and organelles

Disease-fighting proteins

The immunization against measles contains a small amount of dead or an activated music virus. It does not make the child sick but it does stimulate the immune system to make proteins called antibodies which help destroy the measles virus and prevent contraction of the disease

Synthesizing proteins

The instructions for making proteins are contained in the nucleus of the cell and stretches of DNA called genes. When a protein is needed the process of synthesis begins and the information contained in the gene is used to make the protein

Example of limiting amino acid

The limiting amino acid in a food is the one supplied and lowest amount relative to the body's needs. Lysine is the limiting amino acid in wheat. Methionine is the limiting amino acid in beans.

Collagen

The most abundant protein in the body. It is the major protein in ligaments which hold our bones together and then tendons which attach muscles to bones and forms the protein framework of bones and teeth

Protein Complementation

The process of combining proteins from different sources so that they collectively provide the proportions of amino acids required to meet the body's needs.

Protein shape

The shape of a protein is essential to its function. For example the elongated shape of the protein collagen is found in connective tissue and helps give it strength to tendons and ligaments. The spherical shape of the protein hemoglobin contributes to their proper functioning of red blood cells and the linear shape of muscle proteins allow them to overlap and shorten muscles during contraction.

Proteins provide structure and regulation

There are more than 500,000 proteins in the human body each with a specific function

Positive nitrogen balance

What is an intake is greater van nitrogen output. This indicates that there is more protein synthesis and degradation so the body is getting protein and this occurs when the body is growing, during pregnancy, and individuals who are increasing their muscle mass by lifting weights

Proteins and food allergies

When a protein from the diet is absorbed without being completely digested it can trigger a food allergy. The first time the protein is consumed and a piece of it is absorbed in tact it stimulates the immune system. When the same protein is consumed again the immune system sees it as a foreign substance and mounts an attack causing an allergic reaction. Allergic reactions cause symptoms throughout the body and the proteins for milk eggs peanuts tree nuts wheat soy fish and shellfish are common causes of food allergies

Protein shape alteration

When the shape of a protein is altered the protein no longer functions normally. This change and structure is called denaturation which refers to a change from the natural proteins in food are often denature during processing and cooking

Zinc

Whole grains wheat germ legumes nuts tofu fortified breakfast cereals

non essential amino acids

- 11

Essential Amino Acids

- An amino acid that cannot be synthesized by the body in sufficient amounts to meet its needs and therefore must be included in the diet. - there are 9

Essential amino acids

- Histidine , isoleucine, leucine , lysine , methionine, phenylalanine, theronine, tryptophan, valine - the body cannot make new proteins without breaking down existing proteins to provide the needed amino acids

limiting amino acids

- The essential amino acid that is available in the lowest concentration relative to the body's need.

Process of protein synthesis

- amino acids come from protein in the diet and from the breakdown of body proteins some can be made in the body by trans animation - the instructions for protein synthesis come from jeans the process of protein synthesis involves transcription and translation 1. In the nucleus the code for proteins is copied from the DNA into a molecule of messenger RNA 2. The messenger RNA takes the genetic information from the nucleus to ribosomes in the cytosol where proteins are made 3. At the ribosomes Transfer RNA reads the genetic code and delivers the needed amino acids to the ribosome to form a polypeptide chain

PKU

- must limit intake of the amino acid phenylalanine. usually this means limiting their consumption of high protein Foods. The artificial sweetener aspartame in some sodas is the source and the breakdown of aspartame in the digestive tract releases pjenylalanine which cannot be properly metabolized. If they build up large amounts of this amino acid compounds called phenylketones build up in their blood and in infants this interferes with brain development and in pregnant women that cause birth defects

important sources of dietary protein

- plant foods, grains, nuts

amino acid pool

- provide raw materials to synthesize proteins and other molecules All the amino acids in body tissues and fluids that are available for use by the body.

Protein DRI

- the acceptable macronutrient distribution range for protein is 10 to 35% of calories. This range allows for different food preferences and eating patterns. A diet that provides 10% of calories from proteins is relatively low protein diet. 35% of calories receive from proteins through the diet is about twice as much as protein as the average American eats. Unless the diet is chosen carefully that contains 35% of proteins it will tend to include more saturated fat and cholesterol

Phenylketonuria (Pku)

-A genetic disease in which the amino acid phenylalanine cannot be metabolized normally, causing it to build up in the blood. If untreated, the condition results in brain damage. - phenylalanine cannot be converted into tyrosine so tyrosine is an essential amino acid for these individuals

denaturation

-Denaturation Alteration of a protein's three-dimensional structure.

Amino Acids

-The building blocks of proteins. Each amino acid contains an amino group, an acid group, and a unique side chain. - proteins found in plants are made up of different combinations of amino acids and proteins found in animals and because of this difference most plant proteins are not used as efficiently as animal proteins to build proteins in the human body

transanimation

-The process by which an amino group from one amino acid is transferred to a carbon compound to form a new amino acid.

Legumes

-The starchy seed of a plant that produces bean pods; includes peas, peanuts, beans, soybeans, and lentils.

Transport proteins

Help transport materials throughout the body and into and out of cells. The protein hemoglobin which gives red blood cells their color shuttles oxygen to body cells and Carries away carbon dioxide

Steps to produce ATP from amino acids

1. The amino group is removed by De animation and converted into the waste product urea. Urea is removed from the blood by the kidneys and excreted in urine 2. De animation of some amino acids results in three-carbon molecules that can be used to synthesize glucose 3 de animation of some amino acids results and acetyl Co a that enters the citric acid cycle 4. De animation of some amino acids form of molecules that enter the citric acid cycle directly 5. The acetyl co a derived from the breakdown of amino acids can be used to synthesize fatty acids. This occurs when calories and protein are consumed in excess of needs 6. In the final step of aerobic metabolism the energy released from the amino acid molecules is transferred to ATP

Non-essential amino acids

11 amino acids that can be made in the body. Under certain conditions some of the non-essential amino acids cannot be synthesized in sufficient amounts to meet the body's needs and these are there for referred to as conditionally essential amino acids

Amino acids

20 amino acids are commonly found in proteins in each kind of protein contains a different number comma combination, and sequence of amino acids which gives proteins their specific functions and unique characteristics in food

Protein deficiency

A concern in the developing world but not a problem in the economically developed societies where plan animal sources of proteins are abundant. Usually a deficiency occurs along with a general lack of food and other nutrients. The protein energy malnutrition is used to refer to a Continuum of conditions ranging from pure protein deficiency called kwashiorkor to an overall energy deficiency called marasmus. Occurs when the tide is very low in protein or when protein needs are high as they are in young children hence kwashiorkor is typically found in children and this word means the disease that the first gets when a second child is born because the older child is no longer breastfed and the child receives a watered-down version of the diet eaten by the rest of the family which is low in protein and often high in fiber and difficult to digest and because the child may not be able to get a large enough quantity of adequate protein deficiency occurs more quickly

Protein-Energy Malnutrition (Pem)

A condition characterized by loss of muscle and fat mass and an increased susceptibility to infection that results from the long-term consumption of insufficient amounts of energy and/or protein to meet the body's needs.

Celiac Disease

A disorder that causes damage to the intestines when the protein gluten is eaten.

Marasmus

A form of protein-energy malnutrition in which a deficiency of energy in the diet causes severe body wasting. - depletion of fat stores - malnutrition in 1st year cases declines in intelligence and learning ability

Kwashiorkor

A form of protein-energy malnutrition in which only protein is deficient. - characterized by swollen belly which results from fluid accumulating in the abdomen and fat accumulating in the liver. Growth is impaired but because energy intake is not necessarily low, the child may not appear thin. Lack of protein causes low immune function , changes hair color, and impairs nutrient absorption - can be triggered by infectious disease - some fat stores are retained b/c energy intake is adequate

Food labels and allergens

A label must indicate whether the product contains any of the eight major food allergens including milk, eggs, peanuts, tree nuts, fish, selfish, so, and wheat

Protein quality

A measure of how good the protein is in a food at providing the essential amino acids the body needs to synthesize proteins. Because animal amino acid patterns are similar to humans than animal proteins in our diet generally provide a mixture of amino acids that better matches our needs and the amino acids that are provided by plant proteins. Animal proteins tend to be digested more easily than plant proteins and only protein that is digested can contribute amino acids to meet the body's requirement. Foods of animal origin are generally sources of high-quality protein or complete dietary protein and when your diet contains high quality protein you don't have to eat as much total protein

Recommended protein

Adult males consume almost 100 grams of protein per day and adult females about 68 grams. The RDA for protein for adults is .8 grams per kilogram of body weight. For a person weighing 70 kilograms or 174 pounds the RDA is 56 grams of protein per day. Rdas have also been developed for each of the essential amino acids but these are not a concern in typical diet planning

Amino acid and protein structure

All amino acids have the same basic structure. How they are linked together in the polypeptide chain determines the three dimensional shape and function of the protein. All amino acids have a similar structure that includes an amino group and an acid group, giving them their name, but each has a different side chain. Of the 20 amino acids and proteins 9 or considered dietary Essentials because they cannot be made in the body

Proteins with contractile properties

Allow muscles to move various parts of the body

Enzymes

Almost all chemical reactions in the body require the help of enzymes and each enzyme has a structure or shape that allows it to interact with the specific molecules in the reaction it accelerates

Amino acid synthesis functions

Amino acids are used to make other nitrogen containing molecules including neurotransmitters, the units that make up DNA and RNA Kama the skin pigment melanin, the vitamin niacin , creatine phosphate which is used to fuel a muscle contraction comma and histamine which causes blood vessels to dilate. In some situations amino acids from proteins provide energy or synthesize glucose or fatty acids. The amino acids for these functions come from the proteins consumed in the diet and from the breakdown of body proteins and these amino acids I referred to collectively as the amino acid pool.

Amino acid pool

Amino acids enter the available pool from the diet and from the breakdown of body proteins period of approximately 300 grams of protein synthesized by the body each day only about 100 grams are made from the amino acids consumed in the diet. The other 200 grams are produced using amino acids recycled from protein broken down in the body. Amino acids in the pool can be used to synthesize body proteins and other nitrogen containing molecules to provide energy or synthesize glucose and fatty acids

Producing ATP from amino acids

Amino acids from dietary or body protein can be used to produce ATP. First the amino acid group nh-2 must be removed through a process called deanimation. The remaining compound composed of carbon hydrogen and oxygen can then be broken down to produce ATP are used to make glucose or fatty acids

Peptides

Amino acids linked by peptide bonds are called peptides. When two amino acids are linked they form a dipeptide and three form a tripeptide. Polypeptide chains may contain hundreds of amino acids and the final structure of a protein molecule consists of one or more folded polypeptide chains

Food Intolerances

An adverse reaction to a food that does not involve the production of antibodies by the immune system.

Food Sensitivities

An adverse reaction to a food that does not involve the production of antibodies by the immune system.

Diet high in protein

As protein intake increases so does the production of protein breakdown products such as urea which must be eliminated from the body by the kidneys and this increases the workload of the kidneys which may speed the progression of renal failure in people with kidney disease. It's not clear whether a high protein diet increases the likelihood of developing kidney disease in people with normal kidney function. Because high protein diet increase the amount of waste that must be excreted in urine The increased water loss which can be a problem if the kidneys are not able to concentrate urine as is the case for infants. Feeding a newborn and infant formula to find protein increases the amount of water loss which can lead to dehydration.

Protein absorption

Because protein must be broken down in order to be absorbed proteins consumed in the diet enter the body as a collection of individual amino acids not functioning proteins. Supplements of specific proteins therefore do not retain their functions in the body. Supplements of enzymes that function in the GI tract such as lactase which is taken to prevent the symptoms of lactose intolerance retain enzyme activity long enough to break down the lactose in the intestine but are also eventually digested to amino acids which are then absorbed. Amino acids from protein digestion into your body by crossing the Lumen of the small intestine into the mucosal cells and then into the blood. This process it involves one of several energy requiring amino acid transport system. Let me know acids with smaller structures use the same transport system. As a result amino acids May compete with one another for absorption. If there is an excess of anyone is amino acids sharing a transport system more of it will be absorbed slowing the absorption of competing amino acids this competition for absorption is usually not a problem because foods contain a variety of amino acids none of which are present in excessive amounts. However when people consume amino acid supplements the supplemented amino acid May overwhelm the transport system reducing the absorption of other amino acids that share the same transport system

Regulating protein synthesis

Both the types of proteins made and when they are made are carefully regulated by increasing or decreasing gene expression. When a gene is expressed the protein that codes for is made. Not all genes are expressed in all cells or at all times. Only the proteins that are needed are made in any given time period which genes are expressed is also affected by genetic background and by the nutrients and other food components we can soon

Vitamin B12

Can be replaced with products fortified with this vitamin such as a beverages , rice milk, almond milk common breakfast cereals, fortified nutritional yeast

Vitamin D

Can be supplemented with Sunshine Products fortified with vitamin D such as solar beverages rice milk almond milk breakfast cereals and margarine

Protein

Can be supplemented with soy-based products, legumes, seeds, nuts, greens, most vegetables

Nitrogen balance

Current protein intake recommendations are based on nitrogen balance studies. Studying nitrogen balance allows researchers to evaluate protein balance because most of the nitrogen we consume comes from dietary protein. Most of the nitrogen we lose is excreted in urine and smaller amounts are lost in feces, skin, sweat, menstrual fluids, hair, and nails. When your body is in nitrogen balance your nitrogen intake equals your nitrogen losses so you are consuming enough protein to replace losses. Nitrogen balance is negative when you're losing body protein and positive when the amount of body protein is increasing

Limiting amino acids

During the synthesis of a protein a shortage of one amino acid can stop the process. If the missing amino acid is a non-essential amino acid that can be made in the body and protein synthesis can continue. Most and non-essential amino acids are made through a process called transamination which involves transferring the amino group from one amino acid to a carbon-containing molecule to form the you needed amino acid. If the missing amino acid is an essential amino acid the body cannot make the amino acid but it can break down its own protein to obtain it allowing protein synthesis to proceed. If an amino acid cannot be supplied protein synthesis will stop. The essential amino acid that is present in shorter Supply relative to the body's needs for it is called the limiting amino acid because lack of this amino acid limits the ability to synthesize proteins.

Amino acid structure

Each amino acid consists of a central carbon atom that is bound to a hydrogen atom, and amino group which contains nitrogen, and acid group, and the side chain. The nitrogen and amino acids distinguishes proteins from carbohydrates and fats. All three contain carbon, hydrogen, and oxygen but only protein contains nitrogen. The side chain of amino acids vary in size and structure and they give different amino acids their unique properties.

Iron

Legumes tofu dark green leafy vegetables dried fruit whole grains and fortified grain products absorption is improved when iron containing foods are consumed with vitamin C found in citrus fruits Tomatoes strawberries and dark green vegetables

Benefits of vegetarian diet

Lower body weight relative to height and reduce the incidence of other chronic diseases such as diabetes cardiovascular disease high blood pressure and some types of cancer. The lower body weight is a result of lower energy intake due to higher intake of fiber which makes the diet more filling. The reductions in the risk of chronic diseases may be due to lower body weight and the fact that these diets are lower in saturated fat and cholesterol. Higher and whole grains legumes nuts vegetables and fruits which adds fiber vitamins and minerals antioxidants and phytochemicals which have been shown to lower disease risk.

Food combinations consumed in traditional diet

Mini food combinations consumed in traditional diets take advantage of complementary plant proteins such as lentils and rice or chickpeas and rice and India, rice and beans in Mexico and South America, hummus in the Middle East, and bread and peanut butter in the United States

Athletes and protein intake

Most athletes can meet protein needs by consuming the RDA of .8 grams per kilogram of body weight but endurance athletes and strength athletes benefit from higher protein intakes. Can easily meet protein needs through diet alone. Endurance athletes May benefit from the daily consumption of 1.2 - 1.4 grams per kilogram of body weight. Strength athletes such as weightlifters and bodybuilders need extra protein because it provides the raw materials needed for muscle growth so 1.2 - 1.7 grams per kilogram of body weight. Day is recommended

MyPlate dietary guidelines

Most protein per serving are the dairy in protein groups. 1 cup of milk provides about 8 grams of protein, one ounce of meat or fish 7 grams, one half cup of beans or one fourth cup of nuts or seeds provide 6 - 10 grams. Each serving from the grains group and the vegetables group provides 224 grams so choosing the recommended number of servings of these groups provides a significant proportion of proteins. Encourage replacing foods high in solid fats with those lower in solid fats and calories. Eat more fish

Protein intake during pregnancy

Protein needs are increased during pregnancy and lactation to support the expansion of maternal blood volume, the growth of the uterus and breasts, the formation of the placenta, and the growth and development of the fetus. The RDA for pregnant women is 25 grams of protein per day which is higher than the recommendation for non-pregnant women period and extra 25 grams per day is also needed during lactation to provide protein for the production of breast-milk

Protein a source of energy

Proteins can be broken down and there are amino acids used to provide energy or synthesize glucose and fatty acids. When the diet does not provide enough energy to meet the body's needs body protein is used to provide energy. Because our body does not store protein, functional body proteins such as enzymes and muscle proteins must be broken down to yield amino acids which can then be used as fuel or to make glucose. This ensures that cells have a constant energy Supply but robs the body of the functions performed by these proteins

Regulatory proteins

Proteins help regulate fluid balance through their effect on osmosis blood proteins help hold fluid in the blood because they contribute to the number of dissolved particles in the blood. If protein levels in the blood fall too low water leaks out of the blood vessels and accumulates in the tissues causing swelling known as edema. Proteins also regulate fluid balance because some are membrane Transporters which pump dissolved substances from one side of the membrane to the other

Regulatory protein functions

Proteins such as enzymes which speed up biochemical reactions and transport proteins that travel in the bladder help materials across membranes regulate processes throughout the body

Protein RDA for older adults

RDA for protein is not different for older adults but because there is a decrease in the energy needs with AJ the diet must be higher in protein relative to calories than in younger adults. There is also evidence that older adults May benefit from a diet with more protein. Declining muscle mass is a problem that affects health and the ability to maintain Independence so protein intake that meets or many believe exceeds the current RDA along with strength training exercise May delay loss of muscle mass and help maintain physical function and Optimal Health

Plant proteins

Rich in fiber, phytochemicals, and monounsaturated and polyunsaturated fats. Provide B vitamins except vitamin B12 and Supply iron, think, and calcium but often these minerals are less absorbable then they are from animal products. Plant foods are excellent sources of fiber, phytochemicals, unsaturated fats which are good for health

Proteins role in body's defense mechanism

Skin which is made up primarily of proteins is the first barrier against infection and injury. Foreign particles such as dirt or bacteria that are on the skin cannot enter the body and can be washed away. If the skin is broken and blood vessels are injured blood clotting proteins help prevent too much blood from being lost. If it before material does get into the body and two bodies which are immune system proteins help destroy it

Sources of protein

Sources of protein have an impact on the amount of protein and variety of amino acids available to the body. It also has an impact on what other nutrients you are consuming. Animal products provide B vitamins and readily absorb all sourced of minerals such as iron, think, and calcium and they are low in fiber however are often high in saturated fat which is the nutrient mix that increases the risk of heart disease

Monosodium glutamate

Summerport having a food intolerant to MSG which is a flavor enhancer made up of the amino acid glutamic acid bound to sodium. It is used in meat tenderizers and although research has been unable to confirm that MSG ingestion causes any adverse reactions some people report experiencing a collection of symptoms such as flushed face, tingling or burning sensation, headache, rapid heartbeat, chest pain, and general weakness that are collectively referred to as MSG symptom complex commonly called Chinese restaurant syndrome.

Food intolerances

Symptoms can range from minor discomfort such as the abdominal distress some people feel after eating raw onion too much more severe reactions

Conditionally essential amino acids

The amino acid tyrosine can be made in the body from the essential amino acid phenylalanine.

Nitrogen Balance

The amount of nitrogen consumed in the diet compared with the amount excreted over a given period.

Protein digestion

The chemical digestion of protein begins in the acid environment of the stomach. Here hydrochloric acid denatures proteins opening there folded structure to make the polypeptide chains more accessible for breakdown by enzymes. Stomach acid also activates the protein digesting enzyme pepsin which breaks some of the peptide bonds in the polypeptide chain leaving shorter polypeptides. Most protein digestion occurs in the small intestine or polypeptides are broken into even smaller polypeptides and amino acids by protein digesting enzymes produced in the pancreas and small intestine. Single amino acids, dipeptide, and tripeptides are absorbed in the mucosal cells of the small intestine

gene expression

The events of protein synthesis in which the information coded in a gene is used to synthesize a protein or a molecule of RNA.

Amino acids as energy

Used for energy when the amount of protein consumed in the diet is greater than the need to make body proteins and other molecules. This occurs in most American diets. The body first uses amino acids from the diet to make body proteins and nitrogen containing molecules then because extra amino acids can be stored they are metabolized to provide energy and when your diet includes more energy and protein than you need amino acids can be converted into fatty acid which are stored is triglycerides contributing to weight gain

Risks of vegetarian diets

Vitamin and mineral deficiency are of Greater concern. Of primary concern to vegans is vitamin B12 because this B vitamin is found almost exclusively in animal products vegans must take vitamin B12 supplements or consume Foods fortified with it. Another concern is calcium diets that eliminate these Foods must include plant sources of calcium such as greens and tofu. Much vitamin D comes from milk so this vitamin must be made in the body from exposure to sunlight or consumed. Iron and zinc may be deficient in vegetarian diets because they exclude red meat. Iron and zinc are poorly absorbed through plant sources so lacto-ovo and lacto vegetarian as well as vegans are at risk for deficiencies in these minerals because dairy products are low in iron and zinc. Vegan diets may be low in iodine and the omega-3 fatty acids EPA and DHA

Iodine

iodized salt sea vegetables and food grow near the ocean

Hormones

regulate biological processes. The hormone insulin which is a growth hormone and glucagon are made from amino acids. These protein hormones act rapidly because they affect the activity of proteins that are already present in the cell