nutrition 100

Nota:

• definition: science that studies all interactions between living organisms and food 

1. macros/ micros
   1. macro nutrients

      Nota:

      •  the nutrients we need in larger quantities that provide us with energy, lipid, carbohydrates, and protein. 
   2. micro nutrients

      Nota:

      • provide no energy by are necessary for proper functioning of the body, these are required in small amounts
   3. how do they provide energy?

      Nota:

      • Macronutrients and micronutrients work together to help the body to stay healthy. Biochemical reactions in the body help to release the energy contained in carbohydrates, fats and proteins. Energy is used to maintain body functions and fuel physical work. If more energy is consumed than is needed, over time body weight will increase. some lost to heat, other is stored as fat provide energy when dietary sources are unavailable
2. Classes of nutrients
   1. lipids

      Nota:

      • organic molecules that do not dissolve in water
      • Contribute to texture, taste, flavor, and aroma in food. 
      1. types of lipids
         1. fatty acids

            Nota:

            • Organic molecules made up of a chain of carbons linked to hydrogen atoms with an acid group at one end.
            1. saturated fatty acids

               Nota:

               • contains no carbon-carbon double bonds. Such as red meat. butter, cheese, and whole milk. 
            2. unsaturated fatty acids

               Nota:

               • includes monounsaturated and polyunsaturated fatty acids 
               1. monounsaturated

                  Nota:

                  • contain one carbon-carbon double bond. Includes canola, olive and peanut oils, as well as nuts and avocados. 
                  • in regards to CVD - Decrease LDL cholesterol  - doesnt affect HDL cholesterol 
                  1. oleic acid
               2. polyunsaturated

                  Nota:

                  • Contain more than one carbon-carbon double bond. 
                  1. Omega- 6- Linoleic acid

                     Nota:

                     • corn oil, safflower oil, soybean oil and nuts are sources of the omega- 6 fatty acid. 
                     • in regards to CVD  - decrease cholesterol synthesis in liver  -decrease LDL- cholesterol 
                     2. EPA and DHA are non essential

                        Nota:

                        • EPA- Eicosapentanoic Acid - may reduce risk of death of heart attack  \
                        • DHA - Decasahexanoic Acid - critical for development of central nervous system and retina of eyes.  - helps immune system
                        • Found in fish and fish oils 
                  2. Omega -3- alpha-linolenic acid

                     Nota:

                     • flaxseed, canola oil, and nuts are sources and fish oils are high in longer-chain omega-3  fatty acids. 
                     • have anti-inflammatory properties that protect against heart disease
                     • -decreases blood triglyceride -decreases VLDL triglyceride  -decreases formation of blood clots  -increases HDL-cholesterol when combined with moderate exercise -help maintain a normal heartbeat
                     1. omega- 3 and omega-6 are essential fatty acids
                        1. Role

                           Nota:

                           • important for growth, skin integrity, fertility, and the structure and function of cell membranes. 
                  3. function

                     Nota:

                     • PUFA's help regulate blood pressure and clotting 
         2. triglycerides

            Nota:

            • The major form of lipid in food and in the body. They consist of three fatty acids attached to a glycerol molecule.
            1. monoglyceride

               Nota:

               • 1 fatty acid + glycerol 
            2. diglyceride

               Nota:

               • 2 fatty acids + glycerol 
         3. phospholipids

            Nota:

            •  Types of lipids containing phosphorous. The most common are the phosphoglycerides, which are composed of a glycerol backbone with two fatty acids and a phosphate group attached.
            • - synthesized in the body - soluble in water - form structural lipid layer and hava a functional role in the body. 
         4. sterols

            Nota:

            • Types of lipids with a structure composed of multiple chemical rings.
            1. cholesterol

               Nota:

               • found in animals and increase heart disease. 
               • f
               1. creates hormones

                  Nota:

                  • estrogen and testosterone 
         5. LIPOPROTEINS

            Nota:

            • - Transport particles for water-soluble lipids  - created by combining lipids, phospholipids and proteins  -transports triglycerides, cholesterol, and fat-soluble vitamins from the small intestine and stored lipids from the liver. 
            1. Chylomicrons

               Nota:

               • transport dietary fat from intestine to tissues 
            2. VLDL's

               Nota:

               • Very- low-density-lipoproteins  - transport lipids(mainly triglycerides) synthesized in the body to tissues. 
            3. LDL's

               Nota:

               • low- density lipoproteins - transports cholesterol to body "bad cholesterol"
            4. HDL's

               Nota:

               • High-density lipoprotein transports cholesterol to tissues to the liver "good cholesterol"  -away from the cells to the liver. 
      2. AMDR = 20-35% of kcals
      3. function of lipids

         Nota:

         • - define body shape - provide stored energy  -insulate body and protect internal organs against physical shock 
      4. Cardiovascular Disease & LIPIDS

         Nota:

         • the type of fat in our diet can contribute to, or protect against CVD 
         • main cause is atherosclerosis
         • RISK FACTORS - high blood pressure -physical inactivity - smoking - elevated blood lipids - diabetes - stress  
      5. calculating % energy from fat

         Nota:

         • energy (kcals) from fat =  grams fat x 9 kcals/g fatpercent energy from fat = kcals from fat/ total kcals x100 
   2. proteins

      Nota:

      • they are required for growth, maintenance and repair of body
      1. sources of protein

         Nota:

         • deficiency is rare. 62% of dietary protein comes from meat, poultry, fish, eggs, and dairy products 
         • less commonly consumed are fish, legumes, nuts and seeds
         1. nutrients provided by animals

            Nota:

            • sources of protein, b vitamins and minerals such as iron, zinc, and calcium 
         2. nutrients provided by plants

            Nota:

            • sources of B vitamins, protein, iron, zinc, fiber and calcium, however in less absorbable forms 
      2. amino acids

         Nota:

         • building blocks of protein 
         • essential amino acids cannot be synthesized by the human body in sufficient amounts to meet needs
         • conditionally essential amino acids are essential under certain conditions 
         1. amino acid pool

            Nota:

            • all amino acids in the body tissues and fluids that are available for use by the body energy production, synthesis of glucose or fatty acid, synthesis of nonprotein molecules containing nitrogen 
            1. ATP production & Deamination

               Nota:

               • amino acids can be used to provide energy however, to nitrogen containing amino acid group must be removed from the amino acids in a process called DEAMINATION
               1. 1. supplying glucose

                  Nota:

                  • amino acids breakdown into three carbon compounds to then be used by the liver to synthesize glucose via gluconeogenesis
               2. 2. energy is needed

                  Nota:

                  • carbon structure of the amino acid is converted into acetyl-CoA or compounds that enter the citric acid cycle to produce ATP 
         2. LIMITING AMINO ACID

            Nota:

            • the amino acids needed for protein synthesis come from the amino acid pool
            • If you have an AA that is in short supply and is required then you may break down body stores - if you don't have enough it is called a LIMITING AMINO ACID - it will stop protein synthesis
         3. essential amino acids

            Nota:

            • Amino acids that cannot be synthesized by the human body in sufficient amounts to meet needs and therefore must be included in the diet.
            • histidine, isoleucine, lysine, methionine, phenylalanine, threonine, tryptophan, valine
         4. non-essential amino acids

            Nota:

            • Amino acids that can be synthesized by the human body in sufficient amounts to meet needs.
            • Alanine, arginine, asparagine, aspartic acid (aspartate), cysteine(cystine), glutamic acid (glutamate), glutamine, glycine, proline, serine, tyrosine 
         5. Sickle cell anemia

            Nota:

            • A change in the sequence of amino acids of hemoglobin alters the shape and function of the protein molecule. Sickle cell hemoglobin forms long chains that distort the shape of red blood cells. 
      3. transamination

         Nota:

         • when a nonessential amino acid is not available from the diet, it can be made in the body by the process of transamination 
         • alanine + a- ketoglutarate -> pyruvate + glutamate
      4. protein structure

         Nota:

         • peptide bonds are chemical bonds that link amino acids together
         • peptide bonds are formed between the acid group of one amino acid and the nitrogen group of the next amino acid 
         • a protein is made of one or more poly peptide chains folded into a 3- dimensional shape
         1. protein structure determines function

            Nota:

            • - the final shape of a protein determines its function 
            • connective tissue proteins and collagen are elongated 
            • hemoglobin has a specialized shape 
         2. protein turnover

            Nota:

            • necessary for normal growth and maintenance  of body tissues and for adaptation to changing situations
            • the continuous synthesis and breakdown of body proteins. 
         3. protein synthesis

            Nota:

            • stretches of  DNA called genes dictate what type of protein is synthesized
            1. transcription

               Nota:

               • the process of copying the information in DNA to a molecule of mRNA 
            2. translation

               Nota:

               • the process of translating the mRNA code into the amino acid sequence of a polypeptide chain
            3. mRNA

               Nota:

               • takes genetic information from the nucleus to the ribosome
      5. protein digestion

         Nota:

         • 1. In the mouth, chewing begins the mechanical breakdown
         • 2. in the stomach hydrochloric acid and the enzyme pepsin begin the chemical digestion - hydrochloric acid breaks down protein structure and activate pepsin
         • 3. in the small intestine protein - pancreatic enzymes called proteases break proteins into smaller polypeptides, intestinal enzymes called peptidases complete the digestion of proteins into single amino acids
         • 4. amino acids are absorbed into small intestine cells and go to the liver via the blood
         1. digestion and food allergies

            Nota:

            • triggered when a protein from the diet is absorbed without being completely digested. 
            • proteins frrom milk, eggs, nuts, wheat, soy, shellfish and peanuts are common causes of food allergies
            • a rapid severe allergic reaction is called anaphylaxis
      6. protein functions

         Nota:

         • Provide structure to individual cells and whole body
         • Parts of a cell : cell membrane, cytosol, organelles
         • body structures: skin, hair, muscle
         • collagen: part of bones and teeth
         • enzymes speed up metabolic reactions
         • transport proteins move substances in and out of cells
         • make up the immune system; antibodies help the immune system in fighting off foreign bodies 
      7. protein deficiency

         Nota:

         • PEM- Protein energy malnutrition is a term that covers a range of protein deficiency condition that may include only protein deficiency or protein deficiency plus energy deficiency
         1. Kwashiorkor

            Nota:

            • is a pure protein deficiency. - Due to low protein, high fibre diet for first child when 2nd child born - See bloated abdomen due to fat and fluid accumulation in liver 
         2. Maramus

            Nota:

            • is purely energy deficiency- emancipation- protein excess can increase risk of heart disease - and ketosis is possible 
      8. protein excess

         Nota:

         • elevated protein intakes over long periods of time 
         1. increased water loss

            Nota:

            • only if kidneys arent working properly 
         2. bone health issues

            Nota:

            • when calcium intake is adequate, high protein diets associated with greater bone mass
         3. kidney stones

            Nota:

            • diets high in animal protein and low in fluid may stimulate formation of kidney stones
         4. heart disease

            Nota:

            • high protein diets often high  in SFA and cholesterol and low in fibre may increase risk of heart disease
         5. cancer

            Nota:

            • high protein diets and low in grains, vegetables and fruit may increase risk 
      9. PKU- Phenylketonuria

         Nota:

         • PKU is an inherited disease and can harm certain individuals- attributed to a defective gene  aspartame- a sugar substitute, contains phenylalnine
         • makes phenyl ketones which are toxic to the brain
      10. 10-35% of total kcals
      11. ATP Production

          Nota:

          • 1. the amino group is removed by deamination 
          • 2. deamination of some amino acids produces three carbon molecules that can be used to synthesize glucose via gluconeogenesis 
          • 3. deamination of some amino acids results in two carbon molecules that form acetyl-CoA, which can enter the citric acid cycle or be used to synthesize fatty acids 
          • 4. deamination of some amino acids forms molecules that are intermediates in the citric acid cycle.
          • 5. High- energy electrons from the breakdown of amino acids are transferred to the electron transport chain, where the energy is trapped and used to produce ATP and water. 
      12. Enzyme proteins

          Nota:

          • Enzymes are protein molecules that speed up metabolic reactions but are not used up or destroyed in the process. 
          •  Each of the reactions involved in the production of ATP and the synthesis and breakdown of carbohydrates, lipids, and proteins requires a specific enzyme with a specific structure.
          • Enzymes that function in the body are made by the body and therefore do not need to be consumed in the diet. 
      13. antibodies
   3. carbohydrates
      1. simple carbohydrates

         Nota:

         • can be naturally present in foods
         • or can be added to foods at the table, during processing, or manufacturing.
         1. monosaccharides
            1. glucose

               Nota:

               • circulates in the blood and is the most important carbohydrate fuel for the body.
               • produced in plants through photosynthesis. 
            2. galactose

               Nota:

               • found in large amounts of milk, and is rarely present naturally
            3. fructose

               Nota:

               • also referred to as fruit sugar, Fructose is made up of half sugar, in honey and high-fructose corn syrup, and it's used to sweeten many drinks and foods
         2. disaccharides
            1. maltose

               Nota:

               •  2 molecules of glucose. It's formed when starch is digested and is broken down by salivary amylase
            2. sucrose

               Nota:

               • one molecule of glucose and one molecule of fructose 
            3. lactose

               Nota:

               • "milk sugar" is glucose linked to galactose
      2. complex carbohydrates
         1. polysaccharides

            Nota:

            • consist of long chains of glucose molecules generally not sweet are startch, glycogen and most fibres. 
            1. glycogen

               Nota:

               • storage form of glucose in animals 
               • chains of glucose - quick source of energy
               • stored in the liver and muscles for energy 
            2. fibre

               Nota:

               • Dietary fiber – found in diet Functional fiber - supplement  Soluble fiber – Dissolves in water. Forms a viscous solution. Oats, apples, beans, and seaweed.-       Slows nutrient absorption, “expands” the size of the meal. Insoluble fiber – does not dissolve in water. Wheat bran, rye bran, broccoli.
               • insoluble fibres promote healthy bowel function 
               • insoluble fibres such as wheat bran, increase the bulk of material in the feces. 
               • soluble fibres and resistant starch draw water into the intestine. 
            3. starch

               Nota:

               • storage form of glucose in plants 
               • grains, legumes and tubers are good sources of starch
               • amylose and amylopectin
               • resistance starch:  starch that escapes digestion in the small intestine of healthy people. 
            4. oligosaccharides

               Nota:

               • found naturally in bananas , beans, other legumes, onions, garlic, and artichokes  may protect an infant from infection that cause diarrhea  not digested by human enzymes in the digestive tract, therefore affecting types of bacteria growth and may have beneficial effects of GI health 
      3. glycemic index

         Nota:

         • a ranking of how food affects the glycemic response(relative to glucose) 
         1. glycemic response

            Nota:

            • how quickly and how high blood glucose rises after carbs are consumed 
         2. low glycemic index (55 or less)

            Nota:

            • Foods with a low glycemic index have been shown to help control type 2 diabetes and improve weight loss.
            • foods like- 100% stone ground whole grain bread all bran cereal barley/ pasta/noodles legumes- chickpeas, lentils, kidney beans etc. 
         3. medium glycemic index( 59-69)

            Nota:

            • foods that you can chose more often include whole grain  rye  brown rice  white potato  popcorn 
         4. High glycemic index ( 70 or more)

            Nota:

            • choose less often  - white bread - corn flakes cereal  - short-grain rice  -french fries -pretzels  
      4. DIABETES
         1. type 1

            Nota:

            • autoimmune disease: bodies own immune system destroys insulin-secreting cells. insulin is no longer made 
         2. type 2

            Nota:

            • muscle, liver and fat cells have decreased sensitivity to insulin (insulin resistance)  - decreased insulin production  incidence increasing among younger children because they are overweight
         3. symptoms

            Nota:

            • excessive thirst frequent urination  blurred vison  for type 1- weight loss
         4. treatment

            Nota:

            • consistent healthy diet and regular physical activity  medication if need - insulin or oral meds 
         5. hypoglycemia

            Nota:

            • is a condition in which blood-glucose levels drop below the normal range.  below 2.2 to 2.8mmol/ L of plasma 
            • can cause symptoms including irritability, nervousness, sweating, shakiness, anxiety, rapid heartbeat, headache, hunger, weakness, and sometimes seizure and coma
      5. RDA: 45-65% of kcals
      6. carb digestion

         Nota:

         •  Mouth: salivary amylase starts breaking down carbs    Stomach: nothing happens Small intestine: starch digestion and breakdown of disaccharides by pancreatic amylaseo  Enzymes in villi finish breakdown to monosaccharides   Large intestine: fiber and other indigestible carbs are partially broken down to form short chained fatty acids and gas.
         1. lactose intolerance

            Nota:

            • enzyme activity may begin to decrease at the age of tow, but symptoms of lactose intolerance usually do not become apparent until the age of six and may not be evident until adulthood.  Whether or not an individual retains the ability to digest lactose into adulthood depends on the genes they inherit.  the incidence of lactose intolerance varies in different populations 
      7. ATP
         1. metabolizing glucose for ATP

            Nota:

            • After absorption, monosaccharides travel to the liver. Fructose and galactose are metabolized for energy. 
            •   Glucose may be use for energy or goes into blood for body tissues
         2. cellular respiration - glucose metabolized to produce ATP

            Nota:

            • 1) Glycolysis - in the cytosol of the cell  6 carbon molecule -> two 3- carbon molecule (pyruvate) + high energy electrons + small ATP 
            • 2) Acetyl-CoA formation –  1 Pyruvate -> 1 CO2 + electrons + 1 Acetyl-Coa
            • 3) citric acid cycle  1 Acetyl-Coa + 1 oxaloacetate (4-carbon compound) -> citric acid + 2 CO2 + electrons + ATP
            • 4) Electron Transport chain   - Electron transport chain accepts electrons to make ATP.  - Electrons + oxygen + hydrogen -> water 
         3. Gluconeogenesis

            Nota:

            • synthesis of glucose when carbs aren’t present. Made from amino acids and proteins.
            • in liver and kidney cells 
            •  Amino acids can form pyruvate and oxaloacetate to make glucose
            • Fatty acids and ketogenic acids cannot make glucose because they form acetyl-CoA which cant form pyruvate
            • Gluconeogenesis is essential for meeting the body’s immediate need for glucose, particularly when carbohydrate intake is very low, but it uses amino acids from proteins that could be used for other essential functions, such as growth and maintenance of muscle tissue
      8. dental caries (cavities)

         Nota:

         • The decay and deterioration of teeth caused by acid produced when bacteria on the teeth metabolize carbohydrate.
      9. calculating % energy from carbs

         Nota:

         • energy (kcals) from carbs = grams carbs x 4kcal/ g carb  percent of energy from carb =  kcals from carbs/ total kcals x 100
   4. vitamins

      Nota:

      • Vitamins are organic and can be broken down by heat, air, or acid. 
      • do not directly provide energy to the body, but are necessary for obtaining energy from the macronutrients. 
      1. fortified foods

         Nota:

         • foods to which nutrients have been added to. 
      2. water soluble vitamins
         1. B vitamins
            1. Thiamin (B1)
               1. beriberi

                  Nota:

                  • results in muscle wasting and nerve damage, rare but seen in chronic alcoholism 
                  1. symptoms of deficiency

                     Nota:

                     • depression, weakness, poor coordination, tingling in arms, paralysis
               2. food sources

                  Nota:

                  • wholegrains, enricher cereals, pork, organ meats, legumes, nuts, some leafy greens
               3. function

                  Nota:

                  • synthesis of the neurotransmitter acetylcholine, ribose synthesis, energy production, nerve functioning
            2. riboflavin (B2)
               1. Ariboflavinosis

                  Nota:

                  • inflammation of the mouth and tongue
                  1. symptoms

                     Nota:

                     • cracks of corners of mouth 
               2. food sources

                  Nota:

                  • dairy, whole and enriched grains, leafy greens, vegetables, meats
               3. function

                  Nota:

                  • coenzyme in citric acid cycle, lipid metabolism, and electron transport chain
            3. Niacin (B3)
               1. pellagra
                  1. symptoms

                     Nota:

                     • 3D's : Diarrhea, dermatitis, dementia
               2. food sources

                  Nota:

                  •  beef, chicken, fish, peanuts, legumes, whole and enriched grains, can be made from tryptophan
               3. function

                  Nota:

                  • coenzyme in glycolysis, citric acid cycle electron transport chain, and lipid synthesis
            4. biotin
               1. deficiency symptoms

                  Nota:

                  • dermatitis, nausea, depression and hallucinations
               2. function

                  Nota:

                  • coenzymes in glucose and fatty acid synthesis and amino acid metabolism 
               3. food sources

                  Nota:

                  •  liver, egg yolk, synthesized by bacteria in the gut
            5. pantothenic acid
               1. deficiency symptoms

                  Nota:

                  • fatigue, rash 
               2. food sources

                  Nota:

                  • meat, legumes, whole grains, wisespread in foods 
               3. function

                  Nota:

                  • coenzyme in citric acid cycles and lipid synthesis breakdown 
            6. vitamin B6
               1. forms

                  Nota:

                  • pyridoxal, pyridoxine, pyridoxamine- all can be converted to the active enzyme pyridoxal phosphate 
               2. deficiency symptoms

                  Nota:

                  • headaches, convulsion and other neurological symptoms, decrease in immune function
               3. food sources

                  Nota:

                  • meat, fish, poultry, liver, legumes, whole grains, nuts and seeds
               4. function

                  Nota:

                  • coenzyme in protein and amino acid metabolism, neurotransmiter and hemoglobin synthesis
            7. Folate
               1. Macrocytic anemia
                  1. symptoms

                     Nota:

                     • inflammation of the tongue, diarrhea, poor growth, neural tube defects
               2. food sources

                  Nota:

                  • leafy greens, vegetables, legumes, nuts, seeds, enricher grains, oranges, liver
               3. function

                  Nota:

                  • coenzyme in DNA synthesis and amino acid breakdown 
            8. Vitamin B12
               1. function

                  Nota:

                  • coenzyme in folate and fatty acid metabolism; nerve function
               2. Pernicious anemia

                  Nota:

                  • does not respond to iron supplementation lack of intrinsic factor, macrocytic anemia 
                  1. symptoms

                     Nota:

                     • nerve damage
               3. food sources

                  Nota:

                  • animal products
         2. vitamin C
            1. scurvy
               1. symptoms

                  Nota:

                  • poor wound healing, bleeding gums, loose teeth, bone fragility, joint pain, pinpoint hemorrhages 
            2. food sources

               Nota:

               • citrus fruits, broccoli, strawberries, greens, peppers, potatoes
            3. function

               Nota:

               • coenzyme in collagen synthesis, hormone and neurotransmitter synthesis; antioxidant
         3. choline
            1. liver dysfunction - deficiency
            2. sources

               Nota:

               • egg yolks, organ meats, leafy greens, nuts, body synthesis
            3. function

               Nota:

               • synthesis of cell membranes and neurotransmitters 
      3. fat soluble vitamins
         1. vitamin A
            1. in the diet

               Nota:

               • plant and animal foods are good sources of vitamin A. 
               • preformed vitamin A compounds are known as retinoids
               • preformed vitamin A is found in animals  Provitamin A is found in plants 
               1. retinoids

                  Nota:

                  • the chemical forms of preformed vitamin A: retinol, retinal, and retinoic acid
                  • sources:  Animal foods such as liver, fish, egg yolks and milk and alternative products provide preformed vitamin A.
               2. provitamin A & carotenoids

                  Nota:

                  • carotenoids are yellow, orange and red pigments that give these colour to fruits and vegetables. 
                  • Beta‐carotene (β‐carotene) is the most potent precursor, it is plentiful in dark orange fruits and vegetables such as mangoes, apricots, carrots, etc. also appears in leafy greens where the orange colour is masked by the green colour of cholrophyll. it is also an antioxidant. 
                  • alpha‐carotene (α‐carotene) also provides some provitamin A activity. It can be found in carrots, leafy greens and winter squash. 
                  • beta‐cryptoxanthin (β‐cryptoxanthin), can also provide some provitamin A activity. it can be found in mangoes, papayas, winter squash and sweet red peppers. 
                  • Vitamin A is fairly stable when heated, but may be destroyed by exposure to light and oxygen
                  • Sources: carrots, leafy greens, sweet potatoes, broccoli, apricots, cantaloupe
            2. absorption in the digestive tract

               Nota:

               • they must be released from the protein by pepsin and other protein digesting enzymes to be absorbed. 
               • in the small intestine, the released retinol and carotenoids combine with bile acids and other fat-soluble food component to form micelles, which then facilitate their diffusion into mucosal cells. 
               • absorption of preformed vitamin A is efficient (about 70-90% of what is consumed) 
               • the provitamin carotenoids are less well absorbed, and absorption decreases as intake increase, so large amounts are not well absorbed. 
               • One inside the mucosal cells, much of the β‐carotene is converted to retinoids
               1. ability of absorption

                  Nota:

                  • The fat content of the diet and the ability to absorb fat can affect the amount of vitamin A that is absorbed. A diet that is very low in fat (less than 10 g/day) can reduce vitamin A absorption.
                  • populations with low dietary fat intakes,, vitamin A deficiency may occur due to poor absorption 
                  • medications can also interfere with vitamin A absorption 
            3. functions

               Nota:

               • Vision, health of cornea and other epithelial tissue, cell differentiation, reproduction, immune function
               1. epithelial tissue

                  Nota:

                  • type of tissue that covers all external surfaces of the body. It includes skin and the linings of the eyes, intestines, lungs, vagina and bladder.
                  • keratin- a hard protein that makes up hair and nails. as epithelial tissues cannot differentiate, they get replaced by keratin and these surfaces become hard and dry. 
            4. deficiency diseases and symptoms

               Nota:

               • night blindness, xerophthalmia, poor growth, dry skin, impaired immunity
               1. xerophthalmia

                  Nota:

                  • when vitamin A is deficient, the lack of mucus and the build up of keratin cause the cornea to dry and leave the eye open to infection. 
                  • it begins as night blindness and extreme dryness and progresses to wrinkling, cloudiness and softening of the cornea called KERATOMALACIA. if left untreated, it can progress to permanent blindness. 
            5. toxicity

               Nota:

               • headache, vomiting, hair loss, liver damage, skin changes, bone and muscle pain, fractures, birth defects
         2. Vitamin D
            1. sources

               Nota:

               • egg yolk, liver, fish oils, tuna, salmon, fortified milk, synthesis from sunlight
            2. major functions

               Nota:

               • absorption of calcium and phosphorus, maintenance of bone
            3. deficiency diseases
               1. rickets

                  Nota:

                  • in children: abnormal growth, misshaped bones, bowed legs, soft bones
               2. Osteomalacia

                  Nota:

                  • in adults: weak bones and bone and muscle pain
            4. toxicity

               Nota:

               • calcium deposits in soft tissues, growth impairment, kidney damage
         3. Vitamin E

            Nota:

            • alpha‐tocopherol (α‐tocopherol)-  the most common form of vitamin E in human blood. 
            1. sources

               Nota:

               • Vegetable oils, leafy greens, seeds, nuts, peanuts
            2. major functions

               Nota:

               • antioxidant, protects cell membranes
            3. deficiency symptoms

               Nota:

               • broken red blood cells, nerve damage 
            4. toxicity

               Nota:

               • inhibits vitamin k activity. 
            5. vitamin E absorption

               Nota:

               • depends on normal fat absorption, once absorbed it is incorporated into chylomicrons. and once the chylomicrons are broken down vitamin E is distributed to other lipoproteins and delivered to tissues, however most is taken to the liver. 
               • vitamin E needs increase as polyunsaturated fat intake increase 
         4. vitamin K
            1. forms in the diet

               Nota:

               • phylloquinone- is the form found in plants and the primary form in the diet,
               • a group of vitamin K compounds, called menaquinones are found in fish oils and meats.
            2. sources

               Nota:

               • leafy greens, vegetable oils, synthesis by intestinal bacteria
            3. major functions

               Nota:

               • coenzymes for synthesis of blood-clotting proteins and proteins in bone
            4. disease symptoms

               Nota:

               • hemorrhage
            5. toxicity

               Nota:

               • anemia and brain damage in infants 
      4. enrichment

         Nota:

         • restore lost nutrients
      5. provitamin

         Nota:

         •  compound that can be converted into an active form of a vitamin
   5. minerals

      Nota:

      • Minerals are inorganic and hold on to their chemical structure.
      • do not directly provide energy to the body, but are necessary for obtaining energy from the macronutrients. 
      1. functions

         Nota:

         • serve a wide range of vital structural and regulatory roles in the body. For example, calcium, phosphorus, magnesium and fluoride affect the structure and strength of bone. Iodine is a component of the thyroid hormones, which regulate metabolic rate; chromium plays a role in regulating blood glucose levels and zinc plays an important role in gene expression
         • many minerals serve as cofactors- an inorganic ion or coenzyme required for enzyme activity. 
      2. calcium
         1. food sources

            Nota:

            • milk, cheese and yogurt are the main sources. fish, such as sardines and canned salmon that are consumed in their entireity, including the bones are also a good source, as are legumes and some green veggies such as broccoli, chinese cabbage and kale. 
         2. functions

            Nota:

            • bone and tooth structure, nerve transmission, muscle contraction, blood clotting, blood pressure, regulation, hormone secretion
         3. toxicity

            Nota:

            • Elevated blood calcium, calcification of the kidney, kidney stones, reduced absorption of other minerals
         4. osteoporosis

            Nota:

            • caused by a loss of both the protein matric and the mineral deposits of bone, resulting ina decrease in the toal amount of bone
            • it is a "silent" dieses because it intiually causes no symptoms. by the fifth or sixth decade of life the bones of individuals with this disorder have weakened enough to cause back pain and bone fractures of the spine hip and wrist
            • it is a major health problem in canada, about 2 million people  over the age of 50 have osteoporosis; it occurs in one in three women and one in five men
            1. risk factors
               1. gender

                  Nota:

                  • fractures are twice in common in women as in men. men are larger and heavier than women and therefore have a greater peak bone mass. women lose more bone than men due to post-menopausal bone loss
               2. age

                  Nota:

                  • bone loss is a normal part of aging, and risk increases with age. 
               3. race

                  Nota:

                  • POC have denser bones than white people and southeast asians, so their risk is lower
               4. family history

                  Nota:

                  • having a family member with osteoporosis increases risk 
               5. body size

                  Nota:

                  • individuals who are thin and light have an increased risk because they have less bone mass
               6. smoking

                  Nota:

                  • tobacco use weakens bones
               7. exercise

                  Nota:

                  • weight-bearing exercise, such as walking, jogging throughout life strengthens bone, and increases bone density- lowering the risk 
               8. alcohol use

                  Nota:

                  • long-term alcohol abuse reduces bone formation and interferes with the body's ability to absorb calcium.
               9. diet

                  Nota:

                  • A diet that is lacking in calcium and vitamin D plays a major role in the development of osteoporosis. Low calcium intake during the years of bone formation results in a lower peak bone mass, and low calcium intake in adulthood can accelerate bone loss.
         5. absorption in the body

            Nota:

            • calcium is absorbed by both active transport and passive diffusion. The efficiency of calcium absorption varies with life stage. 
            •  Some calcium can be absorbed by passive diffusion, particularly when calcium concentrations are high; at lower calcium concentrations, absorption occurs primarily by an active transport mechanism that requires vitamin D.
         6. bone: a living tissue

            Nota:

            • bone is an active tissue that is constantly being broken down and reformed in a process called bone remodelling
            • Bone is formed by cells called osteoblasts and broken down or resorbed by cells called osteoclasts
            • cortical or compact bone: dense, compact bone that makes up the sturdy outer surface layer of bones 
            • trabecular or spongy bone: the type of bone that forms the inner spongy lattice that lines the bone marrow cavity and supports the cortical shell
      3. phosphorus
         1. food sources

            Nota:

            • meat, milk products, cereals, baked goods
         2. functions

            Nota:

            • structures of bones and teeth, membranes, ATP and DNA; acid base balance
         3. deficiency symptoms

            Nota:

            • bone loss, weakness, lack of appetite
         4. toxicity

            Nota:

            • calcium resorption from bone
      4. magnesium
         1. functions

            Nota:

            • bone structure, ATP stabilization, enzyme activity, nerve and muscle function
         2. food sources

            Nota:

            • greens, whole grains, nuts, seeds
         3. deficiency

            Nota:

            • nausea, vomiting, weakness, muscle pain, irregular heartbeat
         4. toxicity

            Nota:

            • nausea, vomiting, diarrhea, low blood pressure
      5. sulfur
         1. functions

            Nota:

            • part of amino acids, vitamins, acid-base balance
         2. sources

            Nota:

            • high protein foods, preservatives
3. Canadian Diet
   1. Past:

      Nota:

      • more time spent obtaining food ingredients more time spent preparing foods less variety consumed seasonal foods family sat together to eat meals at a slower pace reasonably-sized portions of food
   2. present:

      Nota:

      • purchase convenient and processed foods spend less time preparing meals more meals eaten outside of the home Restaurants/food outlets families not eating together larger portions
   3. primary concerns

      Nota:

      • Primary concern in the past was obtaining all the nutrients needed for good health. Today, primary concern is balancing consumption of calories to prevent obesity and chronic diseases associated with it, while obtaining essential nutrients.
4. Leading causes of death

   Nota:

   • Heart disease, cancer, stroke. 
5. water/ electrolytes

   Nota:

   • water is a macronutrient, does not provide calories and makes up 60% of the body. 
   1. water
      1. major functions

         Nota:

         • solvent, reactant, protector, transporter, regulator of temperature and pH
      2. deficiency diseases and symptoms

         Nota:

         • thirst, weakness, poor endurance, confusion, disorientation
         1. hyponatremia

            Nota:

            • abnormally low concentration of sodium in the blood. 
            • water moves out of the vessels into the tissues by osmosis, causing them to swell. 
            • swelling in the brain can cause dehydration, convulsions, coma and death
            • early symptoms are similar to dehydration (nausea, muscle cramps, disorientation, slurred speech and confusion 
      3. groups at risk

         Nota:

         • infants, those with fever and diarrhea, elderly, athletes 
      4. toxicity

         Nota:

         • confusion, coma, convulsions
      5. DRI

         Nota:

         • 3.7 L per day for men  2.7 L per day for women 
         1. AI (adequate intake)

            Nota:

            • for pregnancy: 3L/day  water needs increase during pregnancy and lactation. water is used to increase blood volume, produce amniotic fluid and nourish the fetus. 
      6. 60% of body weight is made up of water

         Nota:

         • body water is distributed between intracellular and extracellular compartments. the amount distributed is dependent on concentration of solutes 
         • water will diffuse by osmosis from lower concentration to a compartment with higher concentration. 
      7. water balance

         Nota:

         • intake must balance losses to maintain homeostasis. Water is lost through urine and feces, through evaporation from the skin and lungs and in sweat. 
         • the kidney is the primary regulator of water output. if water intake is low, antidieruretic hormone will cause the kidney to conserve water. If intake is high, more awter will be excreted in the urine. 
   2. electrolytes
      1. sodium
         1. sources

            Nota:

            • table salt, processed foods
         2. function

            Nota:

            • Major positive extracellular ion, nerve transmission, muscle contraction, fluid balance
         3. deficiency symptom

            Nota:

            • muscle cramps
         4. toxicity

            Nota:

            • contributes to high blood pressure
      2. potassium
         1. sources

            Nota:

            • fresh fruits and vegetables, legumes, whole grains, milk and meat
         2. toxicity

            Nota:

            • abnormal heartbeat
         3. function

            Nota:

            • Major positive intracellular ion, nerve transmission, muscle contraction, fluid balance
         4. deficiency symptoms

            Nota:

            • irregular heartbeat, fatigue, muscle cramps
      3. chloride
         1. sources

            Nota:

            • table salt, processed foods
         2. function

            Nota:

            • Major negative extracellular ion, fluid balance
      4. Sodium, Potassium, and Chloride in the Canadian Diet

         Nota:

         • modern diet is high in salt and low in potassium. Canadians tend to eat more processed foods than normally healthy, and don't eat enough fresh, unprocessed foods such as fruits, vegetables, whole grains and fresh meats. These healthy foods are low in sodium and high in potassium. 
      5. electrolytes in the body

         Nota:

         • Almost all of the sodium, chloride and potassium consumed in the diet is absorbed. homeostatic mechanisms act to control the concentration of these electrolytes in the body, where they help regulate fluid balance and are important for nerve conduction and muscle contraction 
      6. basic role

         Nota:

         • sodium chloride and potassium are electrolytes that are important in the maintianence of fluid balance and the formation of membrane potentials essential for nerve transmission and muscle contraction 
      7. hypertension

         Nota:

         • blood pressure that is consistently 140/90 mm of mercury or greater indicates hypertension
         • a diet high in sodium increase blood pressure especially in salt sensitive individuals. High intakes of the minerals potassium, magnesium and calcium help lower blood pressure. 
         • the DASH diet - a diet moderate in sodium and high in potassium, magnesium calcium and fiber, low in fat, saturated fat and cholesterol- lowers blood pressure
6. TRACE ELEMENTS

   Nota:

   • they are required in the body in an amount of 100mg or less per day or present in the body in an amount of 0.01% or less of body weight
   1. IRON
      1. sources

         Nota:

         • comes from both plant and animal sources. much of the iron in animal products is heme iron- found in proteins such as hemoglobin in blood and myoglobin in muscle.  meat , poultry and fish are good sources of heme iron. 
         • nonheme iron is found in plant and animal foods that is not part of the iron complex found in hemoglobin and myoglobin good sources are green vegetables, legumes and whole and enriched grains. 
      2. in the digestive tract

         Nota:

         • it is absorbed into the intestinal mucosal cells. the amount absorbed is dependent on if the iron is heme or nonheme as well as the presence of dietary component that enhance or inhibit iron absorption
         • Heme iron is absorbed more efficiently. The heme binds to receptors on the surface of mucosal cells, allowing it to enter the cells, where the iron is released from the heme group
         • dietary factors that interfere with the absorption of nonheme iron include fibers, phytates found in cereals, tannins found in tea, and oxalates found in some leafy greens such as spinach. these prevent absorption by binding iron in the gastrointestinal tract. 
      3. major functions

         Nota:

         • part of hemoglobin which delivers oxygen to cells; myoglobin, which holds oxygen in muscle; and electron carriers in the electron transport chain; needed for immune function  
      4. deficiency diseases and symptoms

         Nota:

         • iron deficiency anemia; fatigue, weakness, small, pale red blood cells, low hemoglobin
      5. toxicity

         Nota:

         • Iron poisoning can be life threatening. It can damage the intestinal lining and cause abnormalities in the body blood pH, shock and liver failure. Iron overload can happen over time and accumulates in tissues such as the heart and the liver.Most common form of overload: Hemochromatosis. 
      6. iron in the body

         Nota:

         • Ferritin- the major iron storage protein
         • Transferrin- iron transport protein in the blood
         • hemosiderin- insoluble iron storage compound produced by the body when iron exceeds the storage capacity of ferritin
         • iron is essential for the delivery of oxygen to cells
         • DRI for women on birth control is lower than for women not on birth control
   2. ZINC
      1. deficiency

         Nota:

         • At risk: adolescent females, 71yo+, genetic defects, TPN, pregnant women, various diseases
         • vegetarians are 50% more vulnerable- due to lower bioavailability, wise food choices are necessary. 
         • Zinc deficiency results in decreased immune functions 
      2. food sources

         Nota:

         • legumes, nuts, cereal grains, potatoes are fortified with zinc. 
      3. functions

         Nota:

         • Regulates protein synthesis; functions in growth, development, wound healing, immunity, and antioxidant protection
   3. COPPER
      1. food sources

         Nota:

         • organ meats, nuts and seeds, seafood, chocolate, whole grains
      2. functions

         Nota:

         • connective tissue synthesis, maintenance of heart muscle, lipid metabolism, as well as functioning of the immune system and CNS 
      3. deficiency

         Nota:

         • Anemia, poor growth, bone abnormalities
   4. MANGANESE
      1. food sources

         Nota:

         • Best sources are whole grains and nuts, but can also be found in tea and legumes
      2. functions

         Nota:

         • functions in the carbohydrate and lipid metabolism, as well as antioxidant protection
      3. deficiency

         Nota:

         • can result in stunted growth
      4. toxicity

         Nota:

         • can result in nerve damage, 
   5. SELENIUM
      1. food sources

         Nota:

         • organ meats, seafood, eggs, whole grains
      2. functions

         Nota:

         • Antioxidant protection as part of glutathione peroxidase, synthesis of thyroid hormones, spares vitamin E
      3. deficiency

         Nota:

         • Muscle pain, weakness, Keshan disease keshan disease- Keshan disease causes an enlarged heart and poor heart function.
      4. toxicity

         Nota:

         • Nausea, diarrhea, vomiting, fatigue, hair changes
   6. IODINE
      1. sources

         Nota:

         • Iodized salt, salt water fish, seafood, dairy products
      2. function

         Nota:

         • needed for synthesis of thyroid hormone
      3. deficiency

         Nota:

         • Goiter, cretinism, Intellectual Developmental Disorder, growth and developmental abnormalities
   7. CHROMIUM
      1. sources

         Nota:

         • Brewers yeast, nuts, whole grains, mushrooms
      2. function

         Nota:

         • enhances insulin action
      3. deficiency

         Nota:

         • results in high blood glucose
   8. FLUORIDE
      1. sources

         Nota:

         • Fluoridated water, tea, fish, toothpaste- do not eat toothpaste
      2. functions

         Nota:

         • Strengthens tooth enamel, enhances remineralization of tooth enamel, reduces acid production by bacteria in the mouth
      3. deficiency

         Nota:

         • results in dental caries
7. Digestion, Absorption, and Metabolism

   Adjunto:

   • Digestion, Absorption, and Metabolism