Nutri 300 Ch 5 & 9 Review

What three factors make up the total energy requirement for a 24 hour interval?

BMR, Approximation of Total Energy Required, and BMI

Following is a list of foods each weighing one oz: cheddar cheese, bread, potato chips, butter Arrange the foods from lowest calories to highest calorie. Foods with the highest content of _______________ would be expected to have the highest calorie density, while foods with the highest content of ___________ would have the lowest calorie density.

Butter, Potato Chips, Cheddar Cheese, Bread Fat Water

Define: HDL (high density lipoproteins)

High density lipoprotein cholesterol. Lipoproteins, which are combinations of fats (lipids) and proteins, are the form in which lipids are transported in the blood. HDLs transport cholesterol from the tissues of the body to the liver, so the cholesterol can be eliminated in the bile. HDL cholesterol is therefore considered the 'good' cholesterol: The higher the HDL cholesterol level, the lower the risk of coronary artery disease.The average man has an HDL cholesterol level of 40 to 50 mg/dL. In the average woman, HDL levels range from 50 to 60 mg/dL. An HDL cholesterol of 60 mg/dL or higher gives some protection against heart disease. Regular aerobic exercise, loss of excess weight (fat), and cessation of cigarette smoking increase HDL cholesterol levels. When lifestyle modifications are insufficient, medications can be used.

List and describe some factors in our current food environment that have contributed to the increasing prevalence of obesity.

Increased availability of food Increase number of meals eaten away from home Increased portion sizes which is greatly influenced by value pricing

How does the body adapt to severe calorie restriction?

Mineral electrolyte imbalance, resulting in: -High blood pressure -Irregular heart beats

Define: weight cycling

Otherwise known as "Yo Yo Dieting" it refers to rounds of losing weight, only to regain with each weight loss, 1. Loss lean tissue, decreasing BMR 2. Weight regain is mostly fat

What makes a fatty acid saturated versus unsaturated? Which of these fatty acids are solid at room temperature? Which are liquid?

Saturated fatty acids are fully loaded with hydrogens. Each carbon in the fatty acid carries the max number of hydrogens it can hold. The bonds between the carbon atoms are single. With unsaturated fatty acids, however, not every carbon in the fatty acid carries two hydrogens. When fatty acids lack on or more paris of hydrogen atoms, a double bond is formed on its carbon chains. Saturated fatty acids becoming solid at room temperature (aka: Margarine) and Unsaturated fatty acids become liquid at room temperature (oil).

Does the body manufacture cholesterol? Name 3 foods that contain high amounts of cholesterol. What foods contain no cholesterol?

The body manufacturers cholesterol: 80% made by the liver and 20% is from the diet. Egg yolks, shrimp, and organ meats are high in cholesterol.

Define: Plaque

The inflammation that occurs in response to an injury to the artery wall precipitates the development of atherosclerotic plaque. The buildup of plaque can eventually lead to a heart attack or stroke.

What are the best approaches to weight loss?

To lose one 1b of fat per week: Need an energy deficit of 3500 kcals per week or 500 kcals per day. Promote loss of fat, not lean tissue Promote permanent lifestyle changes

Define: Saturated Fatty Acid

fully loaded with hydrogens. Each carbon in the fatty acid carries the maximum number of hydrogens it can hold. The bond between the carbon atoms are single. Characteristics: Fats containing high amounts of saturated fatty acids are solid at room temperature.

Define: Triglycerides

in foods and in body almost all fats occur as triglycerides.

Define: Phospholipid

keep fats dispersed in water. Ability to dissolve in both fat and water Structure: Glycerol + 2 Fatty acids + a Phosphorus-containing compound.

Describe each component of energy expenditure. What factors influence each?

1. Basal Metabolism, expressed as basal metabolic rate -BMR represents: energy expended to maintain the body's metabolic activities at rest. Affected by: -Body Composition: more lean tissue = the higher BMR -Height: if weight same, taller person has higher BMR than shorter person -Thyroid Hormone: regulates basal metabolism, high thyroid levels increases BMR -Growth Stages of the Life Cycle: BMR higher in pregnant woman and children -Age: lean body mass decreases; 2% per decade; voluntary activity decreases 3% per decade -Fasting and Starvation: Lowers the BMR 2. physical activity -the number of calories used for physical activity depends on >Muscle mass volume >Body weight >The activity itself: energy expended influenced by >>Duration of the activity >>Intensity of the activity 3. thermic effect of food -Energy expended to process food -Approx ~5-10% of total energy intake -Energy spent to digest, absorb, transport, metabolize, and store ingested nutrients.

Fat can perform all three nutrient functions. What are these & give an example of each.

1. Provide energy Fats typically provide more than half of the body's energy needs. Fat from food is broken down into fatty acids, which can travel in the blood and be captured by hungry cells. Fatty acids that aren't needed right away are packaged in bundles called triglycerides and stored in fat cells, which have unlimited capacity. 2. Promote growth and development 3. Regulate body processes Phospholipids are a structural component of the cell membrane. >>Also carry fat through the blood Lipids are necessary to maintain health. In our diet, fat is needed to absorb fat-soluble vitamins and is a source of essential fatty acids and energy. In our bodies, lipids form structural and regulatory molecules and are broken down to provide ATP. As discussed earlier, cholesterol plays both regulatory and structural roles: It is used to make steroid hormones, and it is an important component of cell membranes and the myelin coating that is necessary for brain and nerve function. Most lipids in the body are triglycerides stored in adipose tissue, which is body fat that lies under the skin and around internal organs (Figure 5.12). The triglycerides in our adipose tissue provide a lightweight energy storage molecule, help cushion our internal organs, and insulate us from changes in temperature. Triglycerides are also found in oils that lubricate body surfaces, keeping the skin soft and supple.

One pound of body fat contains ___________ kcalories.

3500

Define: Adipocytes

A fat cell, a connective tissue cell that has differentiated and become specialized in the synthesis (manufacture) and storage of fat. The adipocyte is important to the body in maintaining proper energy balance, storing calories in the form of lipids, mobilizing energy sources in response to hormonal stimulation, and commanding changes by signal secretions.

Define: LDL (low density lipoproteins)

A molecule that is a combination of lipid (fat) and protein. Lipoproteins are the form in which lipids are transported in the blood. Low-density lipoprotein (LDL) transports cholesterol from the liver to the tissues of the body. LDL cholesterol is therefore considered the "bad" cholesterol. HDL and LDL cholesterol are NOT FOUND in food. Instead, HDL and LDL are cholesterol transport molecules made by the liver.

Describe characteristics of the eating disorders anorexia nervosa and bulimia nervosa. Describe typical personality traits of individuals with these eating disorders List the adverse side effects of both of these disorders

Anorexia: Self-denial of food to control weight Distorted self image as "fat" Refusal to maintain minimal body weight Typical anorexic: Female 12-18, middle or high socioeconomic status, well-educated, perfectionist. Consequences of Anorexia: Protein energy malnutrition Loss of lean tissue Increased susceptibility to infection Abnormal electrolyte balance -Irregular heart beat Bulimia: Repeated episodes of binge eating Followed by purging: self-induced vomiting or laxatives Female, well educated, eats for emotional comfort, close to ideal weight, after purging, feels shame or guilt Consequences: Fluid & electrolyte imbalance Irritation of esophagus Erosion to teeth Dental caries develop.

Define central obesity (abdominal obesity). What chronic diseases are more likely to occur with this condition?

Associated with greater risk for: -Cardiovascular disease -Diabetes -High blood pressure Compared to fat elsewhere on hte body

How does excessive fat intake influence health?

Cardiovascular Health Excessive fat intake is most detrimental to cardiovascular health. Saturated fat is the leading cause of high cholesterol levels in most adults. It is found in a wide variety of foods, many of which are often promoted as healthy, such as milk, cheese and other dairy products. For optimal heart health, limit your intake of saturated fat to less than 10 percent of your overall calorie intake. Cancer Risk High fat intake may also contribute to the development of cancer. According to the Harvard School of Public Health, breast, colon and prostate cancer have all been linked to excessive fat consumption. Although it does seem that a high intake of animal fat increases the risk of developing breast and colon cancer, research remains contradictory and the exact link between fat intake and cancer is unclear. Some studies have even suggested a link between unsaturated fats and cancer, while others have shown no link at all between cancer and excessive fat intake.

List 4 roles that cholesterol plays in the body. Does cholesterol yield energy?

Cholesterol is used to make bile, vitamin D, steroid hormones, & structural components of the cell membrane. No cholesterol does not yield energy

What type of fat is each lipoprotein transporting?

Chylomicron: Deliveries dietary TG to body cells VLDL: Transports lipids from liver to cells LDL: Transports cholesterol to cells HDL: Picks up cholesterol from cells for recycling or disposal.

What are the dietary recommendations regarding total fat, saturated fat, & cholesterol intakes? Describe 4 ways to reduce intake. What types of foods are high in fat content?

Fats aren't necessarily bad for you. Dietary fat is a nutrient that helps your body absorb essential vitamins, maintains the structure and function of cell membranes, and helps keep your immune system working. Some types of fat, though, may increase your risk of heart disease and other health problems. Fat also has a lot of calories, increasing the risk of weight gain.

Define: Cholesterol

Function: Used to make bile, vitamin D, steroid hormones, & structural component of cell membrane, Does not provide energy Food Sources of Cholesterol: ONLY IN ANIMAL FOODS!!!!. Foods with most cholesterol: Egg yolks, shrimp, organ meats. Body has ability to make cholesterol: Not required in diet Of total cholesterol in body: >>80% made by liver >>20% from the diet High blood cholesterol: causes risk factors for heart disease.

How do saturated, monounsaturated and polyunsaturated fatty acids affect the risk for heart disease?

High saturated fat intake increases the blood's total cholesterol and LDL's. They also raise blood cholesterol alot. Monounsaturated fatty acids decrease blood cholesterol and LDL levels which helps prevent heart disease. HDL's may slightly increase (good) and LDLs are less susceptible to oxidation (also good). Polyunsaturated Fatty Acids: If intake is less than 10% of total calories >Omega 6 will decrease blood cholesterol, LDLs; High amounts may decrease HDLs >Omega 3 will decrease blood cholesterol, LDL, TG >>Blood HDLs: either no effect or increase >>Prevent growth of athersclerotic plaque. >>Prevent blood clot formation

Define: Hydrogenation

Hydrogen atoms added across a double bond(s) in MUFA and PUFA present in vegetable oils MUFA: Monounsaturated Fatty Acids PUFA: Polyunsaturated Fatty Acid

What is the hydrogenation process? Why do manufacturers hydrogenate fats? What are the advantages and disadvantages of hydrogenation?

Hydrogenation is when hydrogen atoms are added across double bonds in MUFA and PUFA present in vegetable oils. This turns a liquid fat in a solid fat (oil > margarine). A saturated fatty acid is formed from a PUFA. Result: a decrease in the number of double bonds Food manufacturers add hydrogenated oils to foods because they are more solid at room temperature and can be stored longer without becoming rancid. A disadvantage of hydrogenation is that in addition to converting some double bonds into saturated bonds, it transforms some double bonds from the cis to the trans configuration. Because the consumption of these synthetic trans fats increases the risk of developing heart disease, the use of partially hydrogenated oils in the food industry has been declining.

What is the ideal % body fat content for a male? Female? For each gender, what % body fat is associated with an increased health risk?

Ideal Male: 8-19% Female: 21-32% Associated with health risk: Male: Young- >22%; Old: >25% Female: Young: >32% Old:>35%

How are LDLs formed, & what are they transporting? Why are high LDL levels undesirable?

LDLs are formed from very low density lipoproteins. They transport cholesterol to the cells. High levels can lead to heart trouble since we don't want to have lots of cholesterol being sent to cells.

Name the 2 essential fatty acids. Name 2 important functions that they serve. What are the main dietary sources for each?

Linoleic acid (omega 6) and Linolenic acid (omega 3). Body cannot make these 18 carbon precursors Essential for the body to make the longer chain (20 and 22 carbons) fatty acids. Both omega-6 and omega-3 fatty acids are important structural components of cell membranes, serve as precursors to bioactive lipid mediators, and provide a source of energy. Long-chain omega-3 PUFA in particular exert anti-inflammatory effects and it is recommended to increase their presence in the diet Both omega-3 (ω-3) and omega-6 (ω-6) fatty acids are important components of cell membranes and are precursors to many other substances in the body such as those involved with regulating blood pressure and inflammatory responses. There is increasing support for omega-3 fatty acids in protecting against fatal heart disease and it is known that they have anti-inflammatory effects, which may be important in this and other diseases. There is also growing interest in the role of omega-3 fatty acids in the prevention of diabetes and certain types of cancer.1 Main Dietary Sources: Linoleic: vegetable oils (corn, safflower, sunflower, cottonseed) Arachidonic: Meats, poultry, fish

Name 2 factors that can increase the level of HDL

Lose Weight Being overweight is a significant risk factor for high LDL levels and low HDL levels. If you are overweight, losing 5 to 10 percent of your body weight can significantly reduce LDL levels. For every 6 pounds you lose, you can also raise your HDL levels by 1 milligram per deciliter, according to MayoClinic.com. Exercise Exercise not only promotes weight loss, it directly improves your cholesterol levels by increasing HDL and decreasing LDL. In fact, regular exercise can help improve your cholesterol levels whether you are overweight or not. Within two months of beginning a regular exercise routine, you can increase HDL levels by 5 percent, according to MayoClinic.com. As an added bonus, regular exercise can help improve your blood pressure and triglyceride levels. Engage in brisk activity, such as walking, swimming or biking, five days a week. The goal is to increase your heart rate. Watch Your Fats When it comes to LDL cholesterol, your diet is often the biggest culprit. Saturated fats significantly raise your LDL levels, while trans fats not only increase LDL levels, but lower HDL levels as well. Limit your saturated fat intake to less than 7 percent of calories by avoiding meat, eggs and full-fat dairy products. Limit trans fat intake to less than 1 percent of calories by limiting processed foods, commercially baked items and margarines. Avoiding these fats can help balance out your LDL to HDL ratio. Unsaturated fats, which are found in nuts, seeds, vegetable oils and fish, can also help improve HDL's anti-inflammatory abilities, according to MayoClinic.com.

What goals should a weight loss program achieve?

Nutritionally adequate diet (never less than 1200 cals/day) Choose foods lower in fat, higher in complex carbs and fiber Include foods like, choosing lower fat varieties (watch portion size) Avoid beverages with calories --Drink water. (8 glasses/day)

What does the term "omega" mean with respect to fatty acids? Describe the roles of the omega fatty acids in disease prevention.

Nutritionists call omega-3 and omega-6 fatty acids "essential" fats for good reason. The human body needs them for many functions, from building healthy cells to maintaining brain and nerve function. Our bodies can't produce them. The only source is food. These polyunsaturated fats are important for another reason. There's growing evidence that they help lower the risk of heart disease. Some studies suggest these fats may also protect against type 2 diabetes, Alzheimer's disease, and age-related brain decline. Omega-6 mostly comes as linoleic acid from plant oils such as corn oil, soybean oil, and sunflower oil, as well as from nuts and seeds. The American Heart Association recommends that at least 5% to 10% of food calories come from omega-6 fatty acids. Omega-3s come primarily from fatty fish such as salmon, mackerel, and tuna, as well as from walnuts and flaxseed in lesser amounts. Scientists are still debating the optimal amount of fat in a healthy diet, as well as the best proportion of omega-6s and omega-3s. For now, there are several simple changes most of us could make to take advantage of their substantial health benefits.

List and discuss the major causes of obesity.

Obesity genes: genes associated with body weight regulation Genetic Influence: -adopted children are more likely to have the weight like their real parents Environmental Influences Physical Inactivity

Define: Linolenic acid

Otherwise known as Omega 3 Fatty Acid linolenic acid is essential for normal growth and development. In the body, linolenic acid is used to make substances called eicosanoids, which regulate inflammation. Linolenic acid is also a component of cell membranes and is converted to the longer chain omega-3 fatty acids eicosapentaenoic acid, or EPA, and docosahexaenoic acid, or DHA. The omega-3 fatty acids deliver numerous health benefits, according to the National Institutes of Health Office of Dietary Supplements.

Define: Lipoproteins

Packages containing triglycerides, cholesterol, and fat-soluble vitamins surrounded by a shell of phospholipids and proteins.

What are lipoproteins, and what function do they perform?

Packages containing triglycerides, cholesterol, and fat-soluble vitamins surrounded by a shell of phospholipids and proteins. transport lipids through the lymph and blood

List the pros and cons of a high protein, low carbohydrate diet. What are the long term risks?

Raises total and LDL cholesterol High uric acid levels -gout Increased urinary calcium loss: potential osteoporosis development Kidney stone formation Nutritionally inadequate

What are the health effects associated with the female athlete triad. Why do these health effects develop?

Restrictive Dieting Overexercising Weight loss Lack of body fat Leads to amenorrhea (no periods) -Diminished hormones Then osteoporosis -Loss of calcium from bones

How do saturated fats, monounsaturated fats & polyunsaturated fats influence LDL, HDL, & total blood cholesterol levels? Give 2 good food sources for each of these types of fatty acids

Saturated fats: coconut oil and palm oil Monounsaturated: olive oil, canola, and peanut oil Polyunsaturated: Safflower, sunflower, corn, soybean, and cottonseed oils

What are trans fatty acids? How are they formed?

Small amounts form naturally, but larger amounts are generated by hydrogenation, which makes unsaturated oils more saturated. These are essentially synthetic fats that can lead to a plethora of health issues.

Where does fat digestion take place? Where is bile made, and what role does it play in digestion? What is the end product of fat digestion? End product of fat absorption? In what form is fat transported immediately after a meal?

Small intestine. Bile is made in the gall bladder and its purpose is to emulsify the fat into tiny droplets. Monoglycerides and fatty acids are absorbed by the absorptive cells lining the upper portion of the small intestine. The end product of fat digestion is fatty acids and of fat absorption is glycerol. Fat's transported as lipoproteins

How do trans fatty acids influence heart disease? Labels stating what ingredient would indicate that trans fatty acids may be present? Name 2 sources of trans fatty acids.

Trans fats raise your bad (LDL) cholesterol levels and lower your good (HDL) cholesterol levels. Eating trans fats increases your risk of developing heart disease and stroke. It's also associated with a higher risk of developing type 2 diabetes. Labels stating "Partially Hydrogenated Fat" indicate that trans fats are present. Fast Food & Baked Goods

What are the three classes of lipids found in foods & in the body?

Triglycerides, which make up most of the lipids found within our body. Two other types of lipids that are important in nutrition but are present in the body in smaller amounts are phospholipids and sterols. Saturated: More hydrogens Unsaturated: Carbon missing

Define: Bile

a bitter greenish-brown alkaline fluid that aids digestion and is secreted by the liver and stored in the gallbladder.

Define: adipocyte

a cell specialized for the storage of fat, found in connective tissue.

Define: metabolic syndrome

a cluster of biochemical and physiological abnormalities associated with the development of cardiovascular disease and type 2 diabetes.

Define hunger, appetite, and satiety and describe how each influences food intake.

a craving for food due to: Physiological Influences >>Empty Stomach: Gastric contractions trigger release of ghrelin. >>Ghrelin: Levels rise 1-2 hours before a meal >>>>>Very low after a meal >>>>>Other GI hormones released due to absence of nutrients in small intestine and low levels of circulating nutrients. Appetite: psychological desire to eat, influence by: >Sight, smell, taste, or thought of food >External cues influencing appetite: >>Presence of food, appealing taste, sight of dessert even after a heavy meal. Satiety: feelings of fullness after a meal; lose the desire to eat. >Early Sensation: >>Presence of food in GI tract causes >>>Stretching of stomach receptors >>>Presence of nutrients in small intestine causes: -Release of satiety hormones >>>Appetite center receives messages -Hunger response turns off

Define: Chlyomicrons

a lipoprotein to transport dietary fat through the blood to the cells in the body.

Define: Linoleic acid

a polyunsaturated fatty acid present as a glyceride in linseed oil and other oils and essential in the human diet. Otherwise known as Omega 6 fatty acid Linoleic acid is part of cell components, and is used to manufacture signaling molecules in the body. If linoleic and linolenic acids are missing, then the longer chain fatty acids become essential in the diet.

Define: Omega-6 fatty acid

a polyunsaturated fatty acid whose carbon chain has its first double valence bond six carbons from the beginning

Define: Omega-3 fatty acid

a polyunsaturated fatty acid, essential for normal retinal function, that influences various metabolic pathways, resulting in lowered cholesterol and triglyceride levels, inhibited platelet clotting, and reduced inflammatory and immune reactions.

Define: leptin

a protein hormone produced by adipose tissue

Define: Eiconsanoids

any of a class of compounds (as the prostaglandins) derived from polyunsaturated fatty acids (as arachidonic acid) and involved in cellular activity Eicosanoids made from omega 6 fatty acids and omega 3 fatty acids have opposing actions in the body.

Define: trans fatty acids

can arise during the process of hydrogenation. Their purpose is to form a solid fat (margarine) from a liquid fat (vegetable oil)

Distinguish between chylomicrons & VLDL.

chylomicrons are lipoproteins that deliver fat to cells in your body. VLDLs are used to transport lipids from liver to cells.

Define: body mass index

current standard for assessing if body weight is healthy. Correlates with disease risk. Correlates with disease risk. Does not directly measure body fat. Formula fails for muscular people. BMI = weight (lbs)/height (inches) x 703

Define: Monounsaturated fatty acid

missing one hydrogen pair in chemical chain. -Contain one double bond

Define: Polyunsaturated fatty acid

missing two or more hydrogen pairs in chemical chain. Contains two or more double bonds

Define: Unsaturated Fatty acid

not every carbon in the fatty acid carries two hydrogens. When fatty acids lack one or more pairs of hydrogen atoms, a double bond is formed on its carbon chain.

Define: ghrelin

released by stomach. Levels rise 1-2 hours before a meal. Very low after a meal. Other GI hormones released due to absence of nutrients in small intestine and low levels of circulating nutrients.

Define: body composition

the more lean tissue, the higher the BMR

Define: Calorie density

the number of calories per gram of food