5-8 nutrition

chapter 8

Chapter 8: Antioxidants and Free Radicals https://www.youtube.com/watch?v=HtF61dxP1zs Oxidation- Formation of Free Radicals Stable atoms contain an even number of paired electrons Free radical: an atom that has lost an electron and is left with an unpaired electron Free radicals are highly reactive and can cause damage to molecules in the cell Normal Oxidative Reactions During Metabolism Free Radicals Excess Free Radicals Cause Damage: Oxidative Stress or Oxidative Damage Free radicals cause damage to Cell membranes Low-density lipoproteins (LDLs) Proteins in the cell Genetic material (DNA) Diseases Linked to Free Radicals (and oxidative stress or damage) Cancer Heart disease Type 2 diabetes Arthritis Cataracts & macular degeneration Alzheimer's disease Parkinson's disease Antioxidants- Powerful Protection Free-radical formation is generally kept under control by antioxidant vitamins, minerals, and phytochemicals FOOD!!! COLOR- eat a rainbow Antioxidant vitamins stabilize free radicals Antioxidant minerals work within antioxidant enzyme systems that limit damage and destroy free radicals Phytochemicals are plant chemicals stabilize free radicals and prevent damage (Phytochemicals are pigments-the colors) Antioxidants and Vision Antioxidant Vitamin E Vitamin E- Protects Cell Membranes Vitamin E is a fat-soluble vitamin made of Tocotrienol—biologically inactive form Tocopherol—biologically active form Functions of vitamin E Primary role is as an antioxidant Protects polyunsaturated fatty acids (PUFAs) Protects low-density lipoproteins (LDLs) Common Food Sources of Vitamin E Vitamin E- Too much Some studies suggest possible links to vascular disease, diabetes, heart failure, and prostate cancer Side effects such as nausea, intestinal distress, and diarrhea have been reported Vitamin E can interfere with anticoagulant medications Vitamin E- Too Little Vitamin E deficiencies are uncommon Can result in fragile red blood cells (erythrocyte hemolysis) Can cause loss of muscle coordination and reflexes Can impair immune function Vitamin C- Essential Water Soluble Vitamin Functions of vitamin C: Antioxidant Synthesis of collagen- most abundant protein in the body Prevents the disease scurvy Enhances the immune system Regenerates vitamin E after oxidation (team approach) Enhances the absorption of iron (go team Vit C) Collagen Collagen Common Food Sources of Vitamin C* Vitamin C- too much Megadoses (ten times or more of the recommended intake) of vitamin C can cause nausea, diarrhea, nosebleeds, and abdominal cramps Can cause iron toxicity in people with hemochromatosis (iron overload in blood) Can lead to kidney stone formation in people with kidney disease Vitamin C- too little Scurvy is the most common vitamin C deficiency disease Bleeding gums, loose teeth, wounds that fail to heal, swollen ankles and wrists, bone pain and fractures, diarrhea, weakness, and depression Anemia can also result from vitamin C deficiency (relationship to iron) Scurvy Selenium- Trace Mineral Found in a few amino acids in the body Functions of selenium Antioxidant—part of the glutathione peroxidase enzyme system Production of thyroxine, a thyroid hormone Neutralizing Peroxide Molecules- Selenium Protection Common Food Sources of Selenium Selenium too much selenium: Selenium toxicity (brittle hair, nails, skin rashes) can result from supplements too little selenium- known deficiencies: Keshan disease: a form of heart disease (cardiomyopathy), Keshan Province in China Kashin-Beck disease: a type of arthritis; disease of bone, NE and SW China Kashin-Beck Disease Copper, Iron, Zinc, and Manganese- Cofactors Cofactor: a compound needed for proper functioning of an enzyme Copper, zinc, and manganese are cofactors for the superoxide dismutase antioxidant enzyme system Copper, iron, and zinc help us maintain the health of our blood (more on iron and zinc to come later) Manganese is an important cofactor in carbohydrate metabolism Food Sources Copper Leafy Greens: Spinach, Kale Swiss Chard Mustard/Collard Greens Asparagus Squash Whole grains Legumes Iron and Zinc Meats: Beef Pork Plant Sources: Beans Soy Shellfish: High source of zinc, and iron Beta-Carotene- Many other Carotenoids Role: A provitamin: inactive precursors that must be converted to the active form of a vitamin in the body The precursor of retinol= active form of vitamin A Functions: A relatively weak antioxidant Effective against oxidation in cell membranes and LDLs Carotenoids generally function: Enhance the immune system Protect skin from damage by UV light Protect eyes from damage Common Food Sources of Beta-Carotene Beta-Carotene too much: Large quantities do not appear to be toxic Skin may turn yellow or orange at high intakes; harmless and reversible HIGH VITAMIN A is TOXIC and DANGEROUS Too little: There are no known deficiency symptoms Another reason why this is not essential Vitamin A- Essential Fat soluble vitamin Excess vitamin A is stored in the liver, adipose tissue, kidneys, and lungs There are three active forms of vitamin A Retinol Retinal Retinoic acid The Three Active Forms of Vitamin A Contributes to cell differentiation (DNA) Contributes to reproduction and bone growth May act as an antioxidant CRITICAL for vision and sight Essential role in immune function Vitamin A Is Essential to Sight Vitamin A Is Essential to Sight Common Food Sources of Vitamin A Vitamin A: too much or too little is permanently harmful Too much: Vitamin A is highly toxic, especially from supplements Birth defects and permanent damage to the liver and eyes can result Too Little: Night blindness is the most common disease of vitamin A deficiency Irreversible blindness (xerophthalmia) Compromised immune function In Depth: Cancer What is Cancer: a group of related diseases characterized by cells growing out of control Composed of three steps Initiation—a cell's DNA is mutated Promotion—altered cell repeatedly divides Progression—cells grow out of control Cancer Initiation Cancer Promotion Cancer Progression Factors that increase cancer risk: Family history of cancer Tobacco use Weight, poor diet, and sedentary lifestyle Infectious agents (e.g., STDs) Sun exposure (ultraviolet radiation) Environmental contaminant exposure other exposures and unknown factors A Normal Lung and the Lung of a Smoker Effects of Tobacco Use Human papillomavirus (HPV) A Lesion Associated with Malignant Melanoma (skin cancer) Signs and Symptoms of Cancer Unexplained weight loss Fever Extreme fatigue Pain Skin changes Changes in bowel habits or bladder function Indigestion or trouble swallowing White patches inside the mouth or on the tongue Unusual bleeding or discharge Any thickening or lump Nagging cough or hoarseness Cancer Treatments Treatment varies according to the location, the cell type, whether or not it has metastasized, and other individual factors Three major types of treatments: Surgery Radiation Chemotherapy NUTRITION PLAYS HUGE ROLE DURING TREATMENT- NUMEROUS COMPLICATIONS Cancer Prevention & Early Detection Check: get screenings and exams Quit: stop smoking and alcohol abuse Move: get regular physical activity Nourish: maintain a recommended weight and eat a balanced, healthful diet (rather vague in text, nutrition plays a VITAL role in prevention) Role of Antioxidants in Cancer Antioxidants may contribute to reducing the risk of cancer: Enhancing the immune system Preventing oxidative damage to cells Inhibiting the growth of cancer cells and tumors Inhibiting the capacity of cancer cells to avoid aging and programmed cell death (apoptosis) Too Much of a Good Thing? New Vitamins and Cancer Study

chapter 6

Chpt 6: Protein Protein Learning Objectives Structure and Function of protein How the body uses protein Quality and quantity of protein - essential Examples of complementary proteins More Protein Learning Objectives Distinctions between animal and plant proteins Benefits of plant proteins and Diet planning around vegetarian meals Dietary protein recommendations Consequences when dietary protein is inadequate or over-consumed What Are Proteins? Large, complex molecules found in the cells of all living things Critical components of all the tissues of the human body Function in metabolism, immunity, fluid balance, and nutrient transport Contain a special form of nitrogen our bodies can readily use Why Do We Need Proteins? Cell growth, repair, and maintenance Enzymes Hormones Fluid and electrolyte balance pH balance (acid-base balance) Antibodies to protect against disease Energy source (not preferred) Transport and storage of nutrients Compounds such as neurotransmitters, fibrin, and collagen See more notes below Protein Foods + Other Nutrients Iron Zinc Magnesium Vitamin E Fiber (legumes) Omega-3 and mono-unsaturated fats (fish, eggs, seeds, nuts) B-vitamins (thiamin, niacin, riboflavin, B-6, and B-12) How Are Proteins Made? When two amino acids join together in a peptide bond Amino acids combined in a specific sequence Proteins are made by combining multiple amino acids Form large, complex structure Amino Acids: basic building block of proteins Amino acids are the nitrogen-containing molecules that combine to form proteins Essential amino acids Cannot be produced by our bodies Must be obtained from food Nine of 20 amino acids in our bodies are essential Nonessential amino acids Can be made by our bodies Amino Acids of the Human Body Protein Turnover: Synthesis and Breakdown Protein Organization (structure) Determines Function Digestion and Absorption of Proteins? Stomach acids and enzymes break proteins Digestion continues in the small intestine Pancreatic enzymes (proteins) called proteases complete the digestion of proteins into single amino acids Absorb the single amino acids from small intestine Breaking apart proteins Proteins lose shape (denaturation) Heat Acids and bases Heavy metals Alcohol Denaturation results in an irreversible loss in protein function (not losing nutritional value) Occurs during digestion Occurs during cooking (raw egg vs. cooked egg) Dietary Proteins: 2 categories Incomplete protein: does not contain all essential amino acids in sufficient quantities Growth and health are compromised Considered a "low-quality" protein Complete protein: foods that provide ALL ESSENTIAL amino acids in amounts that support growth and maintenance of tissues Considered a "high-quality" protein High biological value Animal and Plant sources * Examples of Complete Protein Foods: Meat Fish Poultry Cheese Eggs (classic example b/c has exact correct amount and variety of amino acids) Dairy (milk, yogurt, whey) Isolated soy protein Quinoa Buckwheat Hemp and chia seeds Spirulina* Examples of Incomplete Protein Foods: Nuts Seeds Legumes Grains Vegetables ALL vegetables and grains provide protein (~2gm protein/serving) Combining Incomplete Proteins Mutual supplementation: combining two incomplete proteins to make a complete protein Complementary proteins: two protein sources that together supply all nine essential amino acids Example: beans and rice Example: complementary proteins Combining Complementary Foods How Much Protein Should We Eat? People who require more protein include* Children Adolescents Pregnant or lactating women Athletes Vegetarians Older Adults Malnourished or Health Issues Nitrogen balance describes the relationship between how much nitrogen (or protein) we consume and excrete each day Nitrogen Balance Determining Protein Needs How Much Protein Should We Eat? Recommended Dietary Allowance (RDA)- Adults 0.8 grams of protein per kilogram of body weight per day* Dietary Guidelines for Americans: 10-35% of total energy intake should be from protein Based on 2000 kcal/day = 50-175 gm protein/day How Much Protein Should We Eat? Most Americans meet or exceed the RDA for dietary protein This is true for many athletes as well Certain groups of athletes, such as distance runners, figure skaters, female gymnasts, and wrestlers who may "diet", are at risk for low protein intake Recommended Protein Intakes Protein: Much More Than Meat! Many foods other than meat can be good protein sources: including dairy products, eggs, legumes, whole grains, and nuts "Newer" food sources of protein include quorn, quinoa, amaranth, teff, millet, and sorghum Choosing Vegetarian What are the various forms of vegetarian diets? Why do people select vegetarian diets? Can Vegetarian Diets Provide Adequate Protein? Types of Vegetarian Diets Why Vegetarian? People chose vegetarian diets because of Health benefits Ecological reasons Religious reasons Ethical reasons Concerns over food safety Health Benefits of Vegetarian Diets Lower intake of saturated fat and total energy Lower blood pressure Reduced risk for heart disease Reduced risk for some types of cancer Fewer digestive problems Reduced risk for kidney disease, kidney stones, and gallstones Improves blood glucose control, lower risk of T2DM Challenges of Vegetarian Vegetarian diets can be low in some vitamins and minerals (iron, calcium, zinc, vitamins D and B12) Vegetarians takes planning for balanced and adequate diet Soy and other plant sources are an excellent protein source Meal planning includes complementary proteins Vegetarians can find healthy eating tips for vegetarians at MyPlate online LOTS of resources for meatless meals and ways to fit more plant protein into everyday diets Nutrients of Concern in a Vegan Diet Protein Imbalance and Poor Protein Status Excess Protein There is no benefit from eating excess protein Excess beyond what the body is using for repair, maintenance, growth, immune, etc. There are times during life cycle that needs are higher- pregnancy, lactation, early childhood, elderly, athletes Too Much Protein Can Be Harmful Normal Function of Proteins: Fluid Balance Maintaining Fluid & Electrolyte Balance Proteins help regulate electrolytes and fluids Regulate quantities of fluids in compartments of body. Cells must contain a constant amount of fluid- too much can cause rupture, too little makes them unable to function Water can diffuse freely across cell membranes. PROTEIN CANNOT-protein attracts water. Same for water retention within vessels and keeping fluid from entering spaces between cells- too much water in spaces= edema. See more notes below Disorders Related to Poor Protein Intake Protein-energy malnutrition (PEM): inadequate intake of protein AND energy (kcals) There are two common, serious forms Marasmus Kwashiorkor (can have a combination of both) Both are associated with infections, mainly GI, which worsens the malnutrition Marasmus disease resulting from severely inadequate intakes of protein, energy, and other nutrients It is characterized by extreme tissue wasting and stunted growth and development Extreme Malnutrition Kwashiorkor disease resulting from extremely low protein intake Kwashiorkor symptoms include Some weight loss and muscle wasting Edema resulting in distention of the belly Retarded growth and development Kwashiorkor is often seen in children in developing countries Rare in U.S.- but extreme cases* Millions in U.S. live on edge of hunger Inner cities U.S. Native American Reservations Rural areas Some elderly people Hungry and homeless children People suffering from anorexia nervosa People with wasting illnesses such as HIV/AIDS, cancer, or drug and alcohol addictions Under-nutrition is not uncommon in the U.S. Disorders Related to Genetic Abnormalities of Proteins Phenylketonuria (PKU) -a disorder when unable to break down the amino acid phenylalanine (many protein foods) (sweetener aspartame, on food label) Sickle cell anemia causes red blood cells to be mis-shaped that impedes transport to body tissues Cystic fibrosis causes an alteration in chloride transport, leading to a sticky mucus that causes life-threatening respiratory and digestive problems* Sickle Cell Anemia Protein and Heart Disease Foods rich in animal protein tend to be rich in saturated fats. SO...perhaps the issue is not simply QUANTITY of protein but QUALITY of protein. Perhaps a larger quantity of protein is fine when it's from non-animal sources. This is the HOT debate! Protein and Renal Disease Enlarged kidneys or livers in animals- when fed experimentally high protein diets Increases the kidneys' workload in humans- does not appear to damage healthy kidneys or cause kidney disease Okay for healthy kidneys, but worsens kidney disease- high protein diet may increase decline of kidney function. AGAIN, perhaps has to do with source of protein in addition to amount. Protein and adult bone loss Evidence is mixed Excessive protein causes calcium to be spilled from the urine High pro diets from ANIMAL sources + low Calcium and low fruit/veg intake may accelerate osteoporosis Too little protein may weaken the bones- clearly seen with malnourished elderly CONTINUING ON- is it the quantity of protein or the source or both???? Protein and Cancer Effects unclear- somewhat hard to separate if effect from protein or fat Correlation between high intakes of fatty and well-cooked red meats and processed meats and some types of cancer- digestive tract, breast, prostate Some strong evidence that ANIMAL proteins are more related to cancers than vegetable protein sources. Is it quantity or source or both??? The "Blue Zones:" Sardinian Diet

chapter 5

Fats in FOOD and Lipids in BODY Dietary Fat different forms and sources Importance in cooking Taste 9 kcal/gam Lipids in the Body: different forms and storage for different body functions Importance health and wellness Essential fat soluble vitamins Excess storage in adipose tissue (impact on body composition) Why Do We Need Fats? Fat-soluble vitamins Vitamins A, D, E, and K are soluble in fat; fat is required for their transport Fat is essential to many body functions Cell membrane structure Nerve cell transmissions Protection of internal organs Insulation to retain body heat Why Do We Need Fats? Fat provides flavor and texture to foods Fat contributes to making us feel satiated Fats are more energy dense than carbohydrates or protein Fats take longer to digest Types of Dietary Fats Chemically there are different structures of fats in food - differ by degree of "saturation" Regardless of the saturation, the calorie value is the same, all dietary fats yield 9 calories/gram So---- Consider 2 concepts regarding dietary fats: The total amount of fat (all dietary fat sources) in the diet The sources of fat or types of fat in the diet Separately we will address: dietary cholesterol, blood lipids and cholesterol Omega-3 fatty acids vs. omega-6 fatty acids- importance in health Triglyceride (Triacylglyceride) Structure or form of fat in food structure or form of fat we store as "body fat" in adipose tissue (can be mobilized for fuel) TG is the form of fat we store in muscle for fuel EACH strand of the TG is a fatty acid: The fatty acid chain can be short or long, saturated or unsaturated Triglycerides- Form of fat we eat! Form of fat we store in body! Saturated vs. unsaturated Fatty acids -combinations of all types Major Sources of Dietary Fat Dietary fats in foods- plant and animal sources Saturated Fats Animal fats, solid fats Butter, stick margarine, lard, cream/whole milk fat, cheese Beef, pork, poultry Vegetable sources: coconut oil, palm kernel oil, and palm oil Unsaturated Fats Vegetable/plant fats, liquids, oils Monounsaturated Fats avocado, olive, nuts Coconut- HOT food trend Saturated, but....it's primarily medium chain fatty acids (MCTs) Populations with high coconut consumption- do not have the same high rates of atherosclerosis or lipid profiles Healthy when part of a diet high in antioxidants and omega-3 fatty acids Saturated Fatty acids (SFA) Within the body there are physiological and structural functions of saturated fats HOWEVER, the body has the ability to synthesize these, therefore there is NO ESSENTIAL need for these fats in the diet Strong evidence indicates higher intake of dietary saturated fatty acid is associated with higher levels of blood cholesterol and LDL cholesterol- both increase CVD risk. Recommendations: <10% of total calories from SFA, replace with mono- and/or poly-unsaturated <7% of total calories from SFA reduces risk of CVD further It's all very complicated, not all saturated fats are the same, and a goal is to help reduce the fear of eating fat. We do need to eat dietary fat! Major sources of SFA in American diet Regular/Full fat cheese Pizza Desserts- grain based and dairy based Chicken and chicken-mixed dishes Sausage, hotdogs, bacon, ribs Recommendations: Lower use of solid fats in cooking and food preparation- use oils in place of butter, stick margarine, lard Choose lower fat milk and dairy products Trimming fat from meats Choose Leaner cuts of meat Reduce consumption of fried foods Reduce amount/portion/frequency of higher SFA foods, ie: can still enjoy pizza but can reduce number of slices or reduce frequency per week/month and not eat pizza same day as burgers and fries! Not all Saturated Fats are the Same The chain length matters in effect on LDL and sub-fractions Butter and Dairy Fats most strongly INCREASE LDL Beef Fats increase LDL, but not as high as butter/dairy Cocoa Butter- slight increase in LDL Coconut Fat- (medium chain length) - atherogenic in animals based on total serum cholesterol, BUT seem to increase HDL, and not consistent evidence in humans with cholesterogenic effect MORE research in this area is needed (hard to separate the types of saturated fats from whole when looking at real food and meals) Cis and Trans Polyunsaturated Fatty Acids: Not all UNsaturated fats are healthy Trans Fat and CHD Fats and CHD: Application An article discussed that contrary to fad diets in the '80s and '90s, it is not beneficial to decrease overall fat consumption by increasing intake of carbohydrates because levels of both LDL and HDL decrease. (In the Nurse's Health Prospective Study) :Saturated fat was only weakly and non-significantly associated with risk of CHD, which is consistent with its lack of effect on the total cholesterol:HDL ratio" (ONE study, lot of controversy) If this is the case, why is it still important to discuss the need to decrease saturated fat intake but to maintain intake of unsaturated fats? Why is it crucial to discuss the relationship between saturated fat intake and CHD? How to make a healthy heart Dietary Fats and CHD: Simple case A friend with family history of CHD risk claims he read online the body makes fats naturally. This has lead him to think he doesn't have reduce his fat intake because "his body is used to fats." How would you explain the flaw in your friend's reasoning? Fats and CHD: More application An article explains that modest reductions in CHD can occur if one reduces the amount saturated fats he/she consumes. What would you advise to reduce amount of saturated fat intake? Your audience is not convinced that altering their diet can decrease their risk of CHF. How might you explain the link between fatty foods and CHF? Dietary Fat and Health We know strong evidence for dietary fats associated with cardiovascular diseases - heart, stroke Saturated fats and processed meats are also associated with risk for colorectal cancer, prostate cancer, and breast cancer- evidence ins mixed, but meats are often the most commonly associated with risk. often these foods replace healthier options, such as high fiber foods and plant sources, that would be protective Higher body fat contributes to vascular and metabolic diseases- especially when fat accumulates in the liver and around the visceral organs (internal fat) Dietary Fat and Nonalcoholic Fatty Liver Disease Nonalcoholic Fatty Liver Disease In the U.S. NAFLD is the most common form of chronic liver disease. ~ 80-100 million people. Liver inflammation- may progress to scarring and irreversible damage (similar to cirrhosis or damage from excessive alcohol use) Every age group is at risk: 40-50 y.o. who also are at higher risk for CVD, T2DM, and obesity are a group of concern. NAFLD is associated with metabolic syndrome Cluster of problems that arise from abdominal fat, impaired insulin function, hypertension, high TG levels Dietary Fat and Alzheimer Disease Saturated and trans-fatty acids positively associated with risk for Alzheimer Disease Intake of omega-3, omega-3, and other mono-unsaturated fats inversely associated with risk Upper intake level of saturated fat resulted in 2.2 times increases incidence of AD Fats and CHD: Application replacing saturated fats with monounsaturated and polyunsaturated fats has shown great benefits on improved health. Substitution of MUFAs for saturated fats reduces LDL but does not change HDL levels What are some common foods that contain monounsaturated fats? What are some easy, realistic ways to incorporate monounsaturated fats into your diet to replace saturated fats and trans fats? The presence of an allergy to 1 or several type of nut(s) is fairly common, what are some ways that a person with this sort of allergy can incorporate monounsaturated fats into his/her diet? Essential Fatty Acids What about Protective Fats? Essential Fatty Acids Essential fatty acids cannot be synthesized in the body and must be obtained in the diet Omega-6 and omega-3 fatty acids They are precursors to biological compounds called eicosanoids, which regulate cellular function Have a MAJOR role in inflammation and blood pressure Essential Fatty Acids Linoleic acid is found in vegetable and nut oils Alpha-linolenic acid (ALA) is derived from dark-green leafy vegetables, flaxseeds and flaxseed oil, soybeans and soybean oil, walnuts and walnut oil, and canola oil Eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) have important health benefits and are found in fish, shellfish, and fish oils Omega-3 Fatty Acids and Oxidative Stress N-3 FA has role in preventing oxidative stress- which is key to CVD (HTN and dyslipidemia), DM, Alzheimer's Disease, MS, mood disorders, arthritis related inflammation, etc etc. Fact or Fiction Omega 3 Edition Fact or Fiction? Our body can produce Omega 3's on its own, we don't need to consume them. Fiction The truth: Our bodies can't produce Omega-3's. Omega-3 is an essential fatty acid and essential fatty acids your body needs in order to function properly, but your body cannot effectively make these from other substances. Fact or Fiction? Omega 3's can help to reduce inflammation in the body and can help to reduce pain. Fact Research shows that omega-3 fatty acids reduce inflammation and may help lower risk of chronic diseases such as heart disease, cancer, and arthritis. Omega-3 fatty acids are highly concentrated in the brain and appear to be important for cognitive (brain memory and performance) and behavioral function. Fact or Fiction? All Omega 3's are the same Fiction The Truth: Not all Omega 3's are equal. There are 3 main types of Omega-3's: DHA, EPA, and ALA. DHA supports optimal brain and eye development and function and supports heart health. EPA also supports heart health. ALA is used (primarily) as a source of energy. Fact or Fiction? Eating fish is the best way to get healthy Omega 3's. Fiction The Truth: Fish and marine-based supplements are the only ways to get EPA and DHA, two important omega-3 fatty acids. However, walnuts, flaxseed, canola oil, soybeans and some other plant foods offer ALA, a third omega-3 fatty acid. All three types of omega-3 fats can be good sources. Fact or Fiction? Omega 3's or fatty acids cause weight gain. Fiction The Truth: All fats are fats - some are less healthy (saturated and trans fats), some are "protective" (Omega-3s). Regardless of the source, if you eat more calories than you need, you will gain weight. Some foods containing Omega-3 fatty acids (oils and nuts) can be high in calories. Moderation is still key and over-consumption does not equal improved health. Fact or Fiction? People with Rheumatoid Arthritis may have to take fewer NSAIDS to control joint pain and inflammation if they consume a diet with higher Omega 3's Fact An analysis of 17 randomized, controlled clinical trials looked at the pain relieving effects of omega-3 fatty acid supplements in people with RA or joint pain. The results suggest that omega-3 fatty acids, along with conventional therapies such as NSAIDs, may help relieve joint pain associated with these conditions. Pathways of fatty acids Dietary Polyunsaturated Fatty Acids N-3 Anti-Inflammatory Alpha-linolenic acid (ALA) EPA, DHA CVD and sudden death risk thru multiple mechanisms Major pathway in lowering BP Alters platelet function, inflammation endothelial cell function, arterial compliance, and arrhythmia Multiple other health benefits Nervous system development, mood disorders, inflammatory disorders, reduced oxidative stress pathways, and many other disease processes CVD risk, neurological function, inflammatory pathways, and immune diseases N-6 Inflammatory Decreases LDL and total cholesterol Precursor for eicosanoids (prostaglandins, thromboxanes, leukotrienes) RESEARCH: Omega-3 Fatty Acids Omega-3's are antiarrhythmic, antithrombotic, and anti-inflammatory. They can be used to treat hyperlipedimia, hypertension, and rheumatoid arthritis. In contrast, omega-6 fatty acids which are present in most seeds, vegetable oils, and meats, are pro-thrombotic and pro-inflammatory. Omega-3 and omega-6 fatty acids are essential because they are not synthesized by the body and must be obtained through diet or supplementation. Higher concentrations of omega-3 fatty acids are required to reduce elevated triglyceride levels (2-4 g per day) and to reduce morning stiffness and the number of tender joints in pateints with rheumatoid arthritis (at least 3 g per day). Reducing dietary intake of omega-6 fatty acids while increasing consumption of omega-3 fatty acids reduces the inflammatory mediators of RA and consequently allows some patients to reduce of discontinue the use of nonsteroidal anti-inflammatory drugs. Research: Omega 3 Fatty Acids in Inflammation an Autoimmune Diseases. There are at least 13 randomized controlled clinical trials that show benefit from fish oil supplements in patients with rheumatoid arthritis. A common feature of the studies has been a reduction in symptoms and in the number of tender joints. There was also a reduction in the does of analgesic anti-inflammatory drugs. In subsequent meta-analysis, morning stiffness was decreased as well as the number of tender joints Omega-3 and Exercise Omega-3 Fatty Acid in Foods Foods high in Omega 3's (Mix of ALA, DHA, EPA) Anchovies Cabbage Canola Oil Cauliflower Cloves Flax seeds & Flaxseed Oil Halibut Herring (Both Atlantic and Pacific) Mustard Seeds Oregano Oysters (Especially from the Pacific) Pumpkin Seeds Salmon (Especially Farm Raised) Scallops Soybeans & Soybean Oil Tofu Trout (Especially Lake Trout) Walnuts & Walnut Oil Brussels Sprouts Clams Cod Collard Greens Crab Green Beans Haddock Kale Lobster Pollock Romaine Shrimp Snapper Sole Spinach Strawberries Turnip Greens Winter Squash Omega-3 Polyunsaturated Fatty Acids Low CHD in Japan and Greenland thought to be related to high fish consumption Study: 250 mg/d EPA +DHA (1-2 svgs PER WEEK of oily fish) vs. no n-3 intake associated with 36% lower risk of CHD death Little benefit gained from higher intakes Supplements of ALA or plant based n-3 fatty acids do not show reduced incidence of CHD (what do people in non-fish access areas do?) Tough to study differences b/w supplements and fish consumption in populations when hard to quantify actual consumption and what best threshold is for reducing CHD (and other related chronic illnesses that benefit from n-3) Omega-6 Fatty Acids: Discussion Common food sources of linoleic acid in a typical American diet includes: chicken and chicken mixed dishes, grain-based deserts, salad dressing, chips (potato and corn), pizza, yeast breads, fried white potatoes, pasta, Mexican dishes, mayo, quick-breads, eggs, popcorn, sausage, franks, bacon and ribs. Where is the Omega-6 coming from in these foods? Based on this information alone, do you think that linoleic acid would be of high nutritional value? N-3 and Triglyceride Reduction- Important for CVD Well documented relationship b/w fish oil consumption and lowering TG by both dose and baseline TG level <90 mg/dL TG- negligible effect from n-3, unless very high dose consumed >200 mg/dL TG treated with 4 g/d fish oil = 30% lower TG >500 mg/dL TG (risk for pancreatitis)- use of n-3 are adjunctive to nicotinic acid (niacin) and fibrates (chol lowering meds) Lovaza only recommended for pts with TG >500 mg/dL (see notes below) Omega-3 Fatty Acids and Cancer High fish intakes associated with reduced risk of breast and colorectal cancer EPA and DHA shown to reduce expression genes involved in colorectal cancer A large review across several countries evaluating various types of cancer- no associations between plant and marine-derived n-3 fatty acids and incidence of cancer Omega-3 fatty acids and Nervous System DHA critical for nervous system development, esp. retina of eye Low n-3 in diet and plasma/RBC levels of DHA associated with several neurological and visual problems Higher intake of DHA or EPA showed lower risk of cognitive decline or verbal fluency- higher levels DHA assoc with reduced risk of all-cause dementia Recommendations for consumption do not differ from those based on CVD- currently DHA critical for neural development and function Dietary intake during pregnancy and lactation transfers from placenta and breast milk, respectively large longitudinal study reported verbal intelligence quotients were higher among children 6 mo- 8 yrs of mothers who consumed more than 349 g seafood per week during pregnancy than mothers who reported no seafood consumption Long term benefits of early exposure on later child development is uncertain Not recommended to supplement during pregnancy, lactation or infancy (other than use of infant formula) Recommendations 2 servings FISH per week (fatty fish) intake equivalent to 1 g/day of EPA and DHA for secondary prevention of CAD Supplements of EPA and DHA possible alternatives to fish consumption for secondary prevention Food Sources= 1 gm EPA and DHA in meal Omega-3 and Depression (Mood Disorders) Very cool area of research! Generally involves supplemental doses, beyond what can be achieved from food alone: therefore, medicinal/pharmacological Studies using EPA vs. placebo show: Adults with unipolar depression- highly significant improvement after 3 weeks of tx Children 6-12 y.o. with depression- highly significant effects on each rating scale measured (n-3 used as monotherapy) Adults with bipolar after 1 month- 8 of 10 subjects had 50% reduction on Hamilton Depression scores Bottom Line for Omega-3's All Good- SO many health improvements associated with omega-3 fatty acids Eat more! Transition: Lipids in the body 3 classes of lipids Triglycerides (tri-acyl glyceride= tag) Phospholipids Sterols Generally "fat" refers to triglycerides (tags) There are several critical functions/roles of lipids in the body. Phospholipids Sterols Sterols: lipids containing multiple rings of carbon atoms Essential components of cell membranes and many hormones Manufactured in our bodies (NOT ESSENTIAL) Cholesterol is the major sterol found in the body Cholesterol: The Good High concentration of cholesterol in the brain (because it's part of cell membranes and myelin sheath around nerve cells) Cholesterol in the membrane helps maintain cell "integrity" (cell is not fluid or mushy) Helps cell signalling Cholesterol is part of mitochondria and endoplasmic reticulum inside cells (energy production and protein synthesis, respectively) Cholesterol: The Good Brain cells can synthesize cholesterol (which is controversial because of alzheimer's) Cholesterol may be good for learning and memory- especially with connection to sleep. During sleep, cholesterol is needed to make myelin The brain contains 25% of the body's cholesterol (abundant) MYELIN- covers nerve cells to help conduction- synapses- which is critical for all other responses- movement, thinking, learning, etc. A large amount of cholesterol is part of myelin Cholesterol: The Good Precursor for: Vitamin D Other hormones progesterone, testosterone, estrogen Steroid hormones Bile (aids in fat digestion as you all know!) REMEMBER: Cholesterol is SYNTHESIZED in your body- YOU MAKE cholesterol to do good! Why Do We Need Fats? Energy Fat is very energy dense, providing 9 kcal/gram Much of the energy used during rest comes from fat Fat is used for energy during exercise, especially after glycogen is depleted Fat is also used for energy storage Fat Is Used for Energy During Exercise Diagram of an Adipose Cell How Much Fat Should We Eat? The Acceptable Macronutrient Distribution Range (AMDR) for fat 20%-35% of calories should be from fat Athletes and highly active people may need more energy from carbohydrates and can reduce their fat intake to 20-25% of total calories Some endurance athletes have "higher fat" days to boost calories and store intramuscular triacylglyceride for fuel Recognize the Fat in Foods Visible fats are those we can see in foods or can easily see have been added to foods, such as dressing or chicken skin Hidden fats are those added to processed or prepared foods to improve texture or taste, which we may not be aware of, or that occur naturally Read the Nutrition Facts Panel on foods carefully Lower-fat versions of foods may not always be lower in Calories, may have more sugar and more sodium What less dietary fat looks like in food In Depth: Cardiovascular Disease Cardiovascular disease (CVD) Dysfunction of the heart or blood vessels The most common forms: Coronary heart disease, or coronary artery disease Stroke Hypertension, or high blood pressure Peripheral vascular disease In Depth: Cardiovascular Disease Atherosclerosis is a disease in which artery walls build up lipid deposits and scar tissue, impairing blood flow The stiffness that results is commonly called "hardening of the arteries" The result is that the heart must work harder to push blood through the vessels In Depth: Cardiovascular Disease The Chemical Components of Lipoproteins Structure of a Lipoprotein Cholesterol: The Bad Cholesterol: The Bad Hyperlipidemia- both high blood cholesterol and high fat in the blood LDL- damages endothelial cells (along inside of artery) Macrophages attack the LDL- FOAMY (foam cells) LDL cells link together to form large fat deposit- fatty streaks Becomes fibrous (like a scab) Smaller diameter within blood vessel and wall is stiff (calcified) Ten-Year Risk for Cardiovascular Disease In Depth: Cardiovascular Disease Modifiable risk factors for cardiovascular disease include Diet Being overweight Physical inactivity Smoking Type 2 diabetes mellitus Inflammation in the body Abnormal blood lipids Maintaining blood pressure In Depth: Cardiovascular Disease Hypertension= High Blood Pressure is a major chronic disease in the United States HUGE warning sign for risk of stroke and cardiovascular disease For many people, hypertension is hereditary; for others, it can be induced through poor nutrition and exercise habits or a combination of poor habits and heredity The DASH Diet Plan: see link below in notes On Call: Tips to Raise Good Cholesterol

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INTRO TO: Reminder Macronutrients: Carbohydrates Fats Protein Provide energy Required in relatively large amounts Vitamins and Minerals Micronutrients: Vitamins Minerals Do NOT supply energy Required in relatively small amounts Vitamins and Minerals: Overall Functions Micronutrients Assist body functions energy metabolism maintenance of healthy cells and tissues Absorption often low (3-10%) compared to macronutrients (85-99%) often need to be chemically altered before they are active in the body Vitamins are ESSENTIAL Organic compounds- contain carbon Does not mean "organically grown" Fat Soluble Vitamins Large storage capability Toxicity is possible Deficiency symptoms may take many months to develop These vitamins occur in different chemical forms - often need to be converted to active form Fat-Soluble Vitamins Water Soluble Vitamins Minimal storage capability Toxicity is rare Deficiency symptoms occur quickly Excreted in urine when tissues are saturated Often with excess intake from supplements Water-Soluble Vitamins Water-Soluble Vitamins (Con't) Minerals Inorganic Cannot be synthesized by plants or animals Sodium, iron, zinc, magnesium, etc Not digested or broken down prior to absorption Absorption varies Two classifications based on need Major Minerals Trace Minerals Major Minerals: Required in amounts of at least 100 mg/day Body contains 5 g or higher Seven major minerals Major Minerals Major Minerals Trace Minerals Trace Minerals Con't Absorption Depends on: Chemical form absorption of heme iron from meats, fish, poultry is ~25% Absorption of non-heme iron from plant products is ~3-5% Strategies to help increase absorption of minerals Numerous factors bind or interfere with absorption fiber, tannins (tea) Other nutrients within a meal alter absorption Calcium and iron interfere with each other Supplements Supplementation of micronutrients is controversial Risk for toxicity Some subgroups have higher risk Absorption is better from foods (usually animal sources, e.g.: iron) Variety in diet is KEY Foods provide phytochemicals Supplements may alter the balance between nutrients (create relative deficiencies or toxicities) FOOD FIRST! Micronutrients, Health and Disease Risk (associated with reduced risk) Vitamin D and colon cancer, osteoporosis, many other associations* Vitamin E and complications of diabetes Vitamin K and osteoporosis* Calcium and hypertension- DASH meal plan Chromium and type 2 diabetes in older adults* Magnesium and muscle wasting in older adults (sarcopenia) Selenium and certain types of cancer Brief list.....more to come in later chapters Future Research on Micronutrients Do more essential micronutrients exist? Nutrition researchers continue to explore the possibility of other substances being essential Vitamin-like factors (e.g., carnitine) and numerous minerals (e.g., boron) may prove to be essential We don't have nutrient recommendations for these

chapter 7

Where are the Fluids in our Bodies: intracellular fluid 2/3 of total body fluid inside cells Potassium and Phosphorus= electrolytes extracellular fluid 1/3 of total body fluid outside cells Tissue fluid- between the cells within tissues and organs* Plasma- fluid portion of blood that carries the blood cells Sodium and Chloride= electrolytes Functions of Fluids Blood Volume Body Temperature Protects and Lubricates Tissues and Organs Minerals (Electrolytes) in Hydration Fluid and Electrolyte Balance Maintaining Fluid Balance Water lost from the body must be replaced Water is LOST through urine, sweat, evaporation, exhalation, and feces Water is GAINED through beverages, food, and metabolic reactions Metabolic water contributes about 10-14% of the water the body needs Maintaining Fluid Balance- LOSS SIDE Sensible water loss occurs through urine and sweat Most water is lost through urine The kidneys control how much water is reabsorbed; excess water is processed by the kidneys and excreted as urine Insensible water loss occurs through evaporation from the skin or exhalation from the lungs, as well as through feces Diuretics increase fluid loss via the urine Water Content of Various Foods- GAIN SIDE Maintaining Fluid Balance- GAIN SIDE Fluid balance is maintained by different mechanisms prompting us to drink and retain fluid The thirst mechanism occurs from a cluster of nerve cells that stimulate our desire to drink the thirst mechanism is not always sufficient the amount of fluids people drink may not be enough to achieve fluid balance WATER is KEY For a Woman Expending 2,500 kcal/day Water* Can you drink too much water? Becoming overhydrated is rare Can result in a dilution of sodium (hyponatremia) When you don't drink enough water: Dehydration Infants and the elderly are especially vulnerable Non-Water Beverages Milk provides: protein, calcium, phosphorus, vitamin D, and, usually, vitamin A (and fluid) Moderate consumption of beverages with caffeine is safe Most soft drinks, juice drinks, flavored waters, and bottled tea and coffee drinks are loaded with added sugars "Designer waters" - added nutrients and/or herbs can add more than 300 Calories to the day's intake rarely contribute to better health Many energy drinks- contain a high amount of caffeine which can cause a dramatic rise in blood pressure and heart rate also contain a significant amount of added sugar Little More on Electrolytes: SODIUM Functions: Fluid and electrolyte balance Associated with Blood Pressure and pH balance Nerve Impulse Transmission Assists in nutrient transport (Glucose) into cells Sodium Recommended intake 1.5 g/day is required (1500 mg/day) minimum No more than 2.3 g/day is recommended (2300 mg) Sources of sodium Processed foods and restaurant foods are generally high in sodium Adding salt to season or cooking 1 tsp salt = 2300 mg sodium High-Sodium Foods and Alternatives Sodium- Too MUCH Hypernatremia: abnormally high blood sodium concentration Can occur in patients with congestive heart failure or kidney disease Results: high blood volume edema high blood pressure Sodium- Too LOW Hyponatremia: an abnormally low blood sodium level Can result from prolonged vomiting, diarrhea, or sweating Has been seen in ultra or endurance athletes who consume too much water and fail to replace sodium this is why electrolyte sports drinks were designed for athletes- to mimic sweat losses and prevent dehydration and hyponatremia Potassium: Functions and Recommendations Fluid and electrolyte balance Very important in muscle contractions and transmission of nerve impulses High potassium intake helps to maintain a LOWER blood pressure NOT SAFE TO SUPPLEMENT- FOOD FIRST 4.7 gm/day (4700mg) Fruit Vegetables Dairy Whole Grains MANY FOOD SOURCES Common Food Sources of Potassium Potassium too much potassium: Hyperkalemia: a high blood potassium level Can occur in patients with kidney disease Can alter normal heart rhythm, resulting in a heart attack THIS IS WHY IT'S NOT SAFE TO SUPPLEMENT Potassium Too Low: Hypokalemia: a low blood potassium level Can be seen in patients with kidney disease or diabetic acidosis Can occur when taking certain diuretic medications Anorexia Nervosa presents risk FOOD FIRST Clinical nutrition management often needed Chloride Functions Assists with maintaining fluid balance Assists the immune system Component of HCl in the stomach Recommended intake Minimum recommendation is 2.3 g/day (2300 mg) Recall Cystic Fibrosis is genetic disorder involving inadequate transport of Chloride Chloride too much chloride: May lead to hypertension in salt-sensitive patients too low chloride: This is rare but can occur in people with eating disorders Phosphorus Functions The major intracellular electrolyte Required for fluid balance Critical role in bone formation (85% of body's phosphorus is found in bone) Regulates biochemical pathways by activating or deactivating enzymes Found in ATP, DNA, RNA Phosphorus Recommended intake Recommended Dietary Allowance (RDA) for phosphorus is 700 mg/day Sources of phosphorus Widespread in many foods Found in high amounts in foods that contain protein (e.g., meat, milk, eggs, beans) Common Food Sources of Phosphorus Phosphorus too much phosphorus: High blood levels of phosphorus can occur with kidney disease or when taking too many vitamin D supplements Causes muscle spasms, convulsions too low phosphorus: Deficiencies of phosphorus are rare Fluid and Electrolyte Balance Disorders Serious health problems that can occur when fluid excretion exceeds intake include Dehydration Heat illnesses Dehydration: water loss > water intake Commonly due to heavy exercise or high environmental temperatures Infants and the elderly are more at risk Diarrhea Vomiting Fever Burns, including sunburn Poorly controlled diabetes Abuse of diuretics or laxatives Dehydration Dehydration is classified in terms of percentage of weight loss that is exclusively due to the loss of fluids Classifying Dehydration Dehydration is classified in terms of percentage of weight loss that is exclusively due to the loss of fluids Using Urine Color to Gauge Hydration Heat Illnesses- 3 types, linked to dehydration Heat cramps Heat exhaustion Heatstroke Heat Cramps Sport Drinks Science: Is It Hype? Americans' Obsession with Bottled Water Drinking Water: How Much to Drink? Think Before You Drink: Can Water Boost Your Brain?