Nutrition Exam 2

Adequate Intake for Essential Fatty Acids

-Adequate Intake (AI) for alpha-linolenic acid is: 1.6 g per day for men 1.1 g per day for women -Adequate Intake (AI) for linoleic acid is: 17 g per day for men 12 g per day for women -Can be met with foods made with 2 to 3 tablespoons of vegetable fat daily and meals that contain fatty fish at least twice a week

Lipid Transportation

-After absorption, fatty acids, glycerol, monoglycerides, and phospholipid fragments are reassembled into triglycerides and phospholipids -Cholesterol and the reassembled triglycerides are coated with a thin layer of protein, phospholipids, and cholesterol to form chylomicrons

Added Sugar Consumption

-Americans consume about 18% of energy from added sugars 360 kcal/day in a diet that supplies 2000 kcal/day -Regular soft drinks and energy drinks are major sources of added sugars in Americans' diets -According to the Dietary Guidelines, people should limit their added sugar intake to less than 10% of total calories

Rich sources of Starch

-Bread and cereal products made from wheat, rice, barley, and oats -Vegetables such as corn, squash, beans, and peas -Tubers such as potatoes, yams, taro, cassava, and jicama -Regardless of source, each g provides 4 kcal

Carbohydrates

-Carbohydrates are a class of nutrients that is a major source of energy for the body -Also can serve as "glue" that holds cells together -Classified as simple or complex -Plants are rich sources of carbohydrates -Made by using sun's energy to combine carbon, oxygen, and hydrogen from carbon dioxide and water

Glucose for Energy

-Cells metabolize glucose to release the energy stored in the molecule -Carbon dioxide and water form as a result

Glucose for Energy

-Cells need glucose to properly metabolize fat -When not enough glucose is available, ketone bodies form (Chemicals formed from the incomplete breakdown of fat) Ketosis - a condition in which ketone bodies accumulate in the blood; can result in loss of consciousness and death in severe cases RDA for carbohydrates is 130 g per day

Carbohydrate Digestion

-Salivary amylase : an enzyme secreted by salivary glands that begins starch digestion -Stops working soon after food enters the stomach -Any fiber present in food would delay rate at which chyme empties from the stomach (Promotes satiety)

Fatty acids

-Short-chain fatty acids have 2 to 4 carbons -Medium-chain fatty acids have 6 to 12 carbons -Long-chain fatty acids have 14 to 24 carbons Fatty acids are identified by: Number of carbon atoms & The type of bond between carbon atoms

Fiber in the Diet

-Soluble and insoluble fiber provide important health benefits -Only plant foods provide dietary fiber -The Adequate Intake (AI) for fiber is: 38 g/day for men 25 grams per day for women -The typical American diet supplies only 17 grams per day

Starch and Glycogen

-Starch is a storage polysaccharide in plants -Composed of amylose and amylopectin -Glycogen a highly branched storage polysaccharide in animals

Starch and Fiber bonds

-The bonds that link glucose units together in starch are digestible -Enzymes in the human digestive tract cannot break apart the bonds between glucose molecules in fiber

Lipid Absorption

-The majority of lipid absorption occurs in the small intestine -Short- and medium-chain fatty acids diffuse into the absorptive cells of the villi -Enter the capillary network -Long-chain fatty acid absorption requires additional steps

Safety of nonnutritive sweeteners

-The safety of nonnutritive sweeteners has been under scrutiny for decades -Aspartame contains phenylalanine and aspartic acid People with phenylketonuria (PKU) must avoid aspartame -Acceptable Daily Intakes (ADIs) have been established for certain nonnutritive sweeteners

Can Diabetes Be Prevented?

-There is no way to prevent type 1 diabetes -The risk of developing type 2 diabetes can be decreased by therapeutic lifestyle changes Actions, such as avoiding excess body fat, exercising daily, and improving the diet, that promote health and reduce risk for chronic disease

Whole Grain Bread

-To determine whether a product contains whole grains, review the ingredient list on the package label and look for "whole grain . . ." in the name of a major ingredient -According to food-labeling guidelines issued by the FDA, whole grains are intact, ground, cracked, or flaked seeds of cereal grains

Tooth Decay (Dental Caries)

-Tooth decay is associated with consuming simple sugars that stick to teeth -As bacteria metabolize carbohydrates for their energy needs they produce acid that damages tooth enamel -Follow good dental hygiene practices to reduce incidence

Nonnutritive Sweeteners

-a group of compounds that are intensely sweet tasting compared to sugar -Very small amount is needed to sweeten food -Supply little or no energy per serving -Can help control energy intake

Dental Hygeine

If a person does not follow good dental hygiene practices, the debris becomes food for bacteria that will live on teeth. As the bacteria metabolize CARBOHYDRATE, they produce ACID that damages tooth enamel and results in decay.

Insulin Enables Glucose to Enter Cells

If a person has not eaten for awhile, they start to feel hungry and grab something to eat: -Blood glucose levels rise -Insulin is secreted -Enables glucose to enter cells -Enhances energy storage by promoting cellular fat, glycogen, and protein production -Blood glucose levels fall

Insulin Injections

Insulin injections through either an insulin pump or multiple daily insulin injections are necessary for those with type I diabetes

Classes of Lipids

Lipids - a class of nutrients that do not dissolve in water; triglycerides, phospholipids, and sterols - Dissolve in organic solvents -Oil is less dense than water, so it will rise to the top of a solution

Lipid Absorption pt 2

Long-chain fatty acids, bile, cholesterol, and fat-soluble vitamins pack together in micelles

Fructose

Monosaccharide in fruits, honey, and certain vegetables; "levulose" or "fruit sugar"

Galactose

Monosaccharide that is a component of lactose

Glucose

Monosaccharide that is a primary fuel for muscles and other cells; "dextrose" or "blood sugar"

Cis fatty acids:

Most naturally occurring unsaturated fatty acids are cis fatty acids, Cis fatty acids have hydrogen atoms of the double-bonded carbons on same side of hydrocarbon chain

Emulsification

The function of an emulsifier in food prep and manufacturing. Allows foods to mix and be prepared properly. Allows them to coexist

Estimated Number of Americans Diagnosed with Diabetes Mellitus

The rate of diabetes increased substantially, from 5.6 million cases in 1980 to 21.0 million in 2012

Digestion in the Small Intestine

The small intestine is the main site for carbohydrate digestion and absorption Pancreatic amylase- enzyme secreted by pancreas that breaks down starch into maltose molecules Maltase - enzyme that splits maltose molecule Sucrase - enzyme that splits sucrose molecule Lactase - enzyme that splits lactose molecule

Controlling Diabetes

Treatment for diabetes may include diet, exercise, insulin injections, and oral medications Treatment options depend on: Type of diabetes, Age, Current health status

Fats and Oils

Two foods that are rich sources of each fat: Saturated fat: coconut oil, butter fat Monounsaturated fat: sunflower oil, olive oil Polyunsaturated fat: grapeseed oil, walnut oil

Macronutrient Consumption in the United States

Typical American diet 48% of kcal from carbohydrates

Hydrocarbon chain

a chain of carbon atoms bonded to each other and to hydrogen atoms

Prostaglandins

a class of eicosanoids that produce a variety of important effects in the body

Bile salts

a component of bile; aid in lipid digestion -Emulsification -Keeps lipids dispersed in small particles which allows for enhanced breakdown for absorption

Metabolic syndrome

a condition that increases risk of type 2 diabetes and CVD - A syndrome is a group of signs and symptoms that occur together and indicate a specific health problem

Hypoglycemia

a condition that occurs when blood glucose level is too low If the blood glucose level drops too low, the affected person can become confused, and he or she may lose consciousness and die

Saturated fatty acid (SFA)

a fatty acid that has each carbon atom within the chain filled with hydrogen atoms

Unsaturated fatty acid

a fatty acid that is missing hydrogen atoms and has one or more double bonds within the carbon chain

Eicosanoids

a group of long-chain fatty acids with hormonelike functions

Diabetes mellitus

a group of serious chronic conditions characterized by abnormal glucose, fat, and protein metabolism

Epinephrine

a hormone produced by the adrenal glands; secreted in response to declining blood glucose levels

Glucagon

a hormone secreted from the alpha cells of the pancreas that helps regulate blood glucose levels

Insulin

a hormone secreted from the beta cells of the pancreas that helps regulate blood glucose levels

Cholecystokinin (CCK)

a hormone that stimulates the gallbladder to release bile and the pancreas to secrete digestive enzymes including pancreatic lipase

Secretin

a hormone that stimulates the liver to produce bile and the pancreas to secrete bicarbonate-rich pancreatic juice

Fatty acids

a hydrocarbon chain found in lipids; one end of the chain forms a carboxylic acid, and one end forms a methyl group Hydrocarbon chain- a chain of carbon atoms bonded to each other and to hydrogen atoms Omega (methyl) end - the end of a fatty acid containing a methyl (-CH3) group Carboxylic acid - an organic molecule with a carboxyl (-COOH) group

Cholesterol

a lipid found in animal foods; precursor for steroid hormones, bile, and vitamin D Rich sources: Egg yolk, Liver, Meat, Poultry, Dairy products -2/3 made in the liver, 1/3 of cholesterol consumed will make it into our system

Triglyceride

a lipid that has three fatty acids attached to a three carbon compound called glycerol, Comprises 95% of lipids infood and the human body

Glycerol

a three carbon alcohol that forms the "backbone" of fatty acids

Glycemic index (GI)

a tool to measure the body's insulin response to a carbohydrate-containing food

Glycemic load (GL)

a tool to measure the body's insulin response to a carbohydrate-containing food; similar to the glycemic index, but also factors in a typical serving size of the food

Gestational Diabetes

a type of diabetes that develops in some pregnant woman -Embryo can develop birth defects -Mother is more likely to experience health problems during pregnancy

Phospholipid

a type of lipid needed to make cell membranes and for proper functioning of nerve cells; chemically similar to a triglyceride except that one of the fatty acids is replaced by a chemical group that contains phosphorus -Phospholipids are partially water soluble because the phosphorus-containing portion of the molecule is hydrophilic, but it also has a hydrophobic portion

Chylomicron

a type of lipoprotein formed in enterocytes to transport lipids away from the GI tract; they enter into the lacteals

Omega‒6 fatty acid

a type of polyunsaturated fatty acid with the first double bond at the sixth carbon from the omega end of the molecule: Linoleic acid

Omega‒3 fatty acid

a type of polyunsaturated fatty acid with the first double bond at the third carbon from the omega end of the molecule: Alpha-linolenic acid

Alpha linolenic acid

an 18-carbon polyunsaturated fatty acid with three double bonds; an essential fatty acid

Linoleic acid

an 18-carbon polyunsaturated fatty acid with two double bonds; an essential fatty acid

Stearic acid

an 18-carbon saturated fatty acid

Type 1 Diabetes

an autoimmune disease that results in destruction of the beta cells of the pancreas; as a result, insulin must be supplied to the affected person regularly through exogenous sources -Genetic susceptibility and environmental factors, such as viral infections, are associated with the development of the disease

Carboxylic acid

an organic molecule with a carboxyl (-COOH) group

Polysaccharides Carbohydrates

comprised of 10 or more monosaccharides bonded together

Oligosaccharides Carbohydrates

comprised of 3 to 10 monosaccharides bonded together

Added Sugars

sugars added to foods during processing or preparation

glycogenolysis

process by which glycogen is broken down and glucose is released into the bloodstream

lipolysis

process by which triglycerides are broken down and glycerol and fatty acids are released into the blood stream

Alternative Sweeteners

substances that sweeten foods while providing few or no kilocalories

Disaccharides

sucrose, lactose, maltose

Trans fats

unsaturated fatty acids that have a trans double bond, Trans fatty acids have hydrogen atoms of the double-bonded carbons on opposite sides of hydrocarbon chain, More solid at room temperature than cis fatty acids

Lipoproteins

water-soluble structures that transport lipids through the bloodstream

Controlling Diabetes with Diet

The Exchange System and carbohydrate counting, a diabetes management tool in which an individual tracks their daily carbohydrate intake, can help plan diets A diabetes meal plan should focus on: Whole grains, Vegetables, Fruits, Legumes, Poultry, Fish Low-fat dairy foods

Whole versus Refined Grain Products

The FDA allows products made from ground, cracked, or flaked cereal grains to be labeled as "whole grains" Must contain: Starchy endosperm, oily germ, fiber-rich bran seed components Refined grain products are generally low in fiber -Lack the fiber-rich bran seed component

Complex Carbohydrates

-Complex carbohydrates have three or more monosaccharides bonded together

Fiber and Health

-Eating high-fiber foods may reduce a person's risk of: Obesity, Diabetes, certain intestinal tract disorders, and cardiovascular disease -Intestinal bacteria produce gases, so you should gradually increase your fiber intake to reduce flatulence

Transportation of Chylomicrons

-Enter the bloodstream through the left subclavian vein -Circulate through the body -Lipoprotein Lipase (LPL) - an enzyme in capillary walls, breaks down the triglycerides -Nearby cells pick up fatty acids and glycerol to use for energy

Fiber is Not Digested

-Fiber is not digested -Eventually enters large intestine -Bacteria ferment soluble fiber -Used for energy -Insoluble fiber contributes to softer feces

High Fructose Corn Syrup (HFCS)

-High-fructose corn syrup (HFCS) - a syrup obtained from the processing of corn -No conclusive evidence that the use of HFCS causes poor health and or disease -Excess calories from beverages sweetened with HFCS contributes to increased risk for diabetes and heart disease

Glucagon Promotes the Breakdown of Glycogen

-If hunger signals are ignored, the alpha cells of the pancreas secrete glucagon Promotes glycogenolysis - process by which glycogen is broken down and glucose is released into the bloodstream -Stimulates liver and kidneys to produce glucose from amino acids Stimulates lipolysis - process by which triglycerides are broken down and glycerol and fatty acids are released into the blood stream

Carbohydrate Consumption Patterns

-In developing nations, diets supply the majority of energy from unprocessed carbohydrates in whole grains, beans, potatoes, corn, and other starchy vegetables -In industrialized nations, people tend to eat more highly refined starches and added sugars

Triglycerides in Foods

-Most triglycerides contain a mixture of unsaturated and saturated fatty acids, One type of fatty acid predominates -The fat in beef and dairy products contains more saturated than unsaturated fatty acids -Olive oil is a rich source of MUFAs -Liquid corn oil contains a greater proportion of unsaturated than saturated fatty acids

Fiber

-Plants also use complex carbohydrates to make supportive structures and protective seed coats -Most types are polysaccharides Soluble fiber - forms of dietary fiber that dissolve or well in water, include pectins, gums, mucilages and some hemicelluloses Insoluble fiber - forms of dietary fiber that generally do not dissolve in water, include cellulose, hemicelluloses and lignin

Are Carbohydrates Fattening?

-Regardless of whether people consume a high-carbohydrate, high-fat, or high-protein diet, they will maintain their weight as long as their energy intake matches their energy outtake -Foods with high amounts of refined carbohydrates do not satisfy hunger as well as those with more protein or fat -Americans consume excess calories from all foods, contributing to prevalence of obesity

Essential fatty acids

-fatty acids that must be supplied by the diet, linolleic and alpha-linoleic acid are essential fatty acids -Signs of an essential fatty acid deficiency: depressed immune system, trouble regulating blood pressure -Arachidonic acid (AA), eicosapentaenoic acid (EPA), and docosahexaenoic acid (DHA) are all essential fatty acids that are precursors to eicosanoids

Micelle

-water soluble spherical lipid cluster, bile salts create a shell around each cluster, allowing for the structure to be suspended in watery digestive juices -When micelles come close to villi, their contents diffuse into absorptive cells

Hyperinsulinemia

A condition in which the pancreas releases an excessive amount of insulin overtime, condition might contribute to development of type 2 diabetes -Carbohydrate-sensitive people develop hyperinsulinemia after eating foods with GIs of 70 or more like bananas, French fries, bagels, and white rice

Absorption of Monosaccharides

Absorption of monosaccharides mainly occurs in the small intestine: Galactose and glucose is absorbed by active transport. Fructose is absorbed by facilitated diffusion Monosaccharides enter capillary network: Transported to the liver by the hepatic portal vein Simple sugars are: Made into glycogen or fat by liver. Released into bloodstream for energy use

Sucrose

Disaccharide composed of a glucose and a fructose molecule; "table sugar"

Lactose

Disaccharide composed of a glucose and a galactose molecule; "milk sugar"

Maltose

Disaccharide composed of two glucose molecules; "malt sugar"

Signs and Symptoms of Diabetes Mellitus

Elevated blood glucose levels, Impotence (male), Excessive thirst, Sores that do not heal, Frequent urination, Increased appetite with weight loss, Blurry vision, Breath that smells like fruit*, Vaginal yeast infections (adult women), Fatigues easily*, Foot pain, abdominal pain, Confusion*, Numbness

Nutritive Sweeteners

Nutritive sweeteners - substances that sweeten and contribute energy to foods Each gram of mono- or disaccharide supplies 4 kcal

Testing for Diabetes

People who have diabetes need to achieve and maintain normal blood-glucose levels -May rely on daily blood test monitoring Hemoglobin A1c (HbA1c) or glycosylated hemoglobin; blood test used to measure a person's average blood glucose over several month's period of time

Plant sterols and stanols

Plant sterols and stanols - chemicals found in plants that are structurally similar to cholesterol Compete with cholesterol for intestinal absorption, which reduces the amount of cholesterol absorbed Found in: Grains, Fruits, Vegetables, Nuts, Seeds, Legumes -Consuming plant sterols may be an effective way to reduce elevated blood cholesterol levels

Does Sugar Cause Hyperactivity?

Scientific studies do not indicate that sugar increases children's physical activity levels or causes attention deficit hyperactivity disorder (ADHD) Children's excitement and higher-than-usual activity at parties are more likely to result from the occasion than from a particular food

Hyperglycemia

abnormally elevated blood glucose levels; the primary sign of the disease. Over time, under treated or poorly controlled hyperglycemia damages nerves, organs, and blood vessels

Sugar alcohols

alternative sweeteners used to replace sucrose in some sugar-free foods ex. Sorbitol, xylitol, mannitol. -Do not promote dental decay -Not fully absorbed by intestinal tract -Supply 2 kcal/g May cause diarrhea when consumed

Oleic acid

an 18-carbon monounsaturated fatty acid

Lipases

enzymes that break down lipids

Monounsaturated fatty acid (MUFA)

fatty acid that has one double bond within the carbon chain

Polyunsaturated fatty acid (PUFA)

fatty acid that has two or more double bonds within the carbon chain

Fat malabsorption

impaired fat absorption; symptoms include diarrhea, steatorrhea, and rapid weight loss

Resistant starches

found in seeds, legumes, whole grains, and some fruits and vegetables that resist digestion and are not broken down in the human GI tract -Provide health benefits similar to dietary fiber

Monosaccharides

glucose, fructose, galactose

Monoglyceride

lipid that has one fatty acid attached to a three-carbon compound called glycerol

Diglyceride

lipid that has two fatty acids attached to a three-carbon compound called glycerol

Sterols

lipids that have a more chemically complex structure than a triglyceride or fatty acid.

Reactive hypoglycemia

low blood glucose that occurs within 4 hours of eating

Stachyose

nondigestible oligosaccharide made of four monosaccharides

Raffinose

nondigestible oligosaccharide made of three monosaccharides

Dietary fiber

nondigestible plant material

Hydrophilic

part of a molecule that attracts water

Hydrophobic

part of a molecule that avoids water and attracts lipids

Pancreatic lipase

the digestive enzyme that removes two fatty acids from each triglyceride molecule

Omega (methyl) end

the end of a fatty acid containing a methyl (-CH3) group

Partial hydrogenation

the food manufacturing process that adds hydrogen atoms to liquid vegetable oil, forming trans fats -Can be stored for longer periods because they are less likely to undergo oxidation -Raises "bad" cholesterol levels in the blood -Increases risk of heart disease In 2015, FDA determined that partially hydrogenated oils pose a health risk and the agency banned their use in foods -Ban goes into effect in 2018 -To prevent oxidation, manufacturers add antioxidants

Lactose intolerance

the inability to digest lactose properly because of a deficiency in the enzyme lactase -Undigested lactose enters large intestine -Bacteria break down lactose and produce gases and acids Person experiences: Intestinal cramps, Bloating, Flatulence, Diarrhea

Type 2 Diabetes

the most common type of diabetes, beta cells of the pancreas produce insulin, but the hormone's target cells are insulin resistant, leading to elevated blood glucose levels Individuals more susceptible to the disease include: Sedentary, Overweight, Genetically related to a close family member with type 2 diabetes