Nutrition and Health Exam 2 Study Guide
Chapter 6 Key Concepts
• Carbohydrates: the main fuel source for most cells in the human body (brain cells and red blood cells). Along with our cells, these are essential for our muscles too. These yield 4 kcal per gram. There are two forms: monosaccharaides and disaccharides.
- Monosaccharaides: these are simple sugars, which are the basic units of carbs. There are various types in foods: glucose, fructose, and galactose.
• Glucose: the main monosaccharaide in the body and serves as energy for the cells. This is found in corn syrup.
o Absorbed by active absorption.
• Fructose: is fruit sugar, which is quickly metabolized by the body and then converted into glucose or other compounds. This is found in fruit, honey, and soft drinks.
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o Absorbed by facilitated diffusion.
• Galactose: a 6-carbon monosaccharaide that is similar and related to glucose.
o Absorbed by active absorption.
- Disaccharides: formed when 2 monosaccharaides combine. There are various types in foods: sucrose, lactose, and maltose.
• Sucrose: forms when glucose and fructose bond together. These are found in various foods like, sugar cane, table sugar and beets. Don't forget about the age old question of spring break mnsu
• Lactose: forms when glucose binds with galactose during milk synthesis, it is essentially the sugar that is found in milk products.
• Maltose: when starch gets broken down to 2 glucose molecules that are bonded together. This plays a big role in the beer/liquor industry. This is found in sprouted seeds.
• When in need, carbs can take 2 different forms: blood glucose and glycogen. - Blood glucose: a sugar in our blood, also known as dextrose.
- Glycogen: maintains the blood glucose amounts in the events where you haven’t eaten for some time, or if you aren’t eating enough carbs. This is stored in the liver and muscles.
• Polysaccharides: many single sugar units that are bound together to form a chain. These are also known as complex carbs/starch. These are found in fruits, vegetables, and grains. There are 3 types amylose, amylopectin, and glycogen. - Amylose: is a long straight chain of glucose units. This is typically found in vegetables, bread, beans, and pasta. (20% of digestible starches) We also discuss several other topics like economics final exam study guide chapters 1-15
- Amylopectin: is a highly branched chain of glucose units and provides many ends for enzyme action. (80% of digestible starches)
- Glycogen: consists of a chain of glucose units with many branches. It is found in the body and made by the cells.
• Fiber: a group of carbohydrate substances composed of cellulose, hemicellulose, pectins, gums, and mucilages, along with a noncarbohydrate substance called lignin.
• Sweeteners: the stuff that makes the food we eat, taste sweet. There are 2 types: nutritive and alternative/artificial.
- Nutritive sweeteners: these are sweeteners, which provide calories for the body. • Sugars: include all monosaccharaides and disaccharides.
• Sugar alcohols: helps diabetic get the same taste of sugar without consuming any. These are low calorie substitutes so people with weight issues often use them. There are 2 types: sorbitol and xylitol.
o Sorbitol: a sugar alcohol that yields 3 kcal per gram and is found in sugarless gums and dietetic foods.
o Xylitol: a sugar alcohol, which is derived from xylose.
- Alternative/artificial sweeteners: yield little to no calories when eaten. There are many types. We also discuss several other topics like if the mps rises, then the mpc will:
• Saccharin: the oldest alternative sweetener.
• Aspartame: contains phenylalanine, aspartic acid, and methanol. This yields 4 kcal per gram.
• Phenylketonuria (PKU): a disease, which prohibits phenylalanine to be properly metabolized. People who have this condition should avoid aspartame. If you want to learn more check out isye 3025 gatech
• Sucralose: made by adding 3 chlorines to sucrose and cannot be broken down or absorbed. This yields no kcal per gram and is used in gum, baked goods, gelatin, etc.
• Neotame: similar to aspartame, but PKU friendly.
• Acesulfame-K: is an organic acid.
• Stevia: is derived from the South American shrub. This yields no kcal per gram.
• Luo han guo: is the extract from the monk fruit.
• Advantame: is similar to aspartame but much sweeter and PKU friendly. • Enzymes used in carbohydrate digestion help break down the food component, there are many types: We also discuss several other topics like econ 487 class notes
- Amylase: digests starches.
- Maltase: digests maltose into to 2 glycogens.
- Lactase: digests lactose to glucose and galactose.
- Sucrase: digests sucrose to glucose and fructose.
• Glycemic load: a number that estimates how much a person’s blood sugar will rise after eating food.
• The difference between insulin and glucagon:
- Insulin: a hormone released by the pancreas when blood glucose is high. - Glucagon: a hormone, which raises the concentration of glucose in the bloodstream when it becomes low. (Produced by alpha cells)
• There are many diseases/disorders affiliated with carbohydrates. - Primary lactose maldigestion: usually develops during ages 3 to 5, about 75% of the population has this condition but not everyone shows it.
- Secondary lactose maldigestion: a temporary condition, which happens when another condition develops and cause lactase production to decrease. - Lactose intolerance: when you consume lactose and have symptoms consisting of gas, bloating, cramps, and diarrhea.
- Type 1 diabetes: begins in late child hood and is due to total insulin deficiency due to the insulin production cells being damaged. Insulin therapy is needed for this condition.
- Type 2 diabetes: usually happens after age 30 is the more common type. This condition is usually a result of obesity, which causes insulin resistance. - Hypoglycemia: people who take insulin due to diabetes, can develop hypoglycemia I they don’t eat enough.
- Metabolic syndrome: when a person has poor blood glucose regulation, hypertension, increased blood triglycerides, and other health issues. This condition is also known as syndrome X.
• Carb intake recommendations
- RDA for carbohydrates in adults is about 130 grams.
• Sugar intake recommendations
- A moderate intake of added sugars is about 10% a day of the caloric intake, which is about 50 grams of sugar.
- North Americans eat an average of 82 grams of added sugar a day. • Fiber intake recommendations
- Fiber intake should be at least 25 grams a day for women and 38 grams a day for men.
- The average fiber intake in North America for women is about 13 grams a day and 17 grams a day for men.
Chapter 7 Key Concepts
• Lipids: composed of mostly carbon and hydrogen. These yield 9 kcal per gram. • Fatty acids: these are the simplest form of lipids. These are also found in triglycerides.
- Saturated: carbons are bonded together using single bonds. These are usually solid at room temperature. (Example: butter)
- Monounsaturated: a fatty acid with 1 double bond. (Example: nuts) - Polyunsaturated: a fatty acid with 2 or more double bonds. (Example: any processed liquid cooking oils)
- Unsaturated fatty acids are usually liquid at room temperature and exist in 2 forms: cis and trans. (Example: oil)
• Cis: when the hydrogens lie on the same side as the carbon-carbon double bond. These are more common. This causes the fatty acid backbone to bend.
• Trans: when the hydrogens lie across from each other. These occur naturally and are also known as conjugated linoleic acid (CLA). This causes fatty acid backbone to remain straight. (Example: shortening)
- Triglycerides: most common type of lipid, which is found in food and the body. These are 3 fatty acids bonded to glycerol.
• If you remove a fatty acid, it will become a diglyceride.
• If your remove 2 fatty acids, it will become a monoglyceride.
• Phospholipids: built on the backbone of glycerol, with at least one fatty acid replaced with a phosphorus-containing compound.
- These are found all throughout the body, especially the brain.
• Sterols: have a multi-ringed structure that set them apart from other lipids. - Cholesterol: a type of a sterol, which helps in forming hormones and is also in cell structures. This is usually found in food or in the plasma membrane of the cell.
• HDL and LDL are known as the good and bad cholesterol.
• Before menopause, women have higher HDL amounts.
• HDL slows cardiovascular disease development, so this is good cholesterol. • LDL is the bad cholesterol because if it is not quickly cleared from the blood stream, it can lead up to the build up of cholesterol in the blood. • Essential fatty acids: the types we need, and have to consume in order to get. - Omega 3 fatty acid: when the first double bond is 3 carbons from a methyl end. (Example: fish, flaxseed, and walnut)
• Should be consumed to decrease inflammation and blood clotting in the body.
• Excess intake can caused uncontrolled bleeding, a hemorrhage, or stroke.
- Omega 6 fatty acid: when the first double bond is 6 carbons from a methyl end. • Hydrogenation: when hydrogen is added by bubbling hydrogen gas under pressure into liquid oils. It also increases the amount of trans fat in foods. This is bad because trans fat causes heart and inflammatory issues.
- Partial Hydrogenation: the same thing as hydrogenation, but the product is made to be a semi solid.
• Enzymes used in fat digestion help break down the food component, there are many types:
- Lipase: enzyme that breaks down fats.
- Lipoprotein lipase: enzyme that breaks down triglycerides into fatty acids and glycerol.
• Chylomicrons: the largest lipoproteins, which are formed after fat absorption and travel through the lymphatic system and through the blood stream. - When the chylomicrons enter the blood stream, they are broken down by lipoprotein lipase into fatty acids and glycerol.
• Fat intake recommendations
- There is no RDA for the total fat consumption for adults.
- The total fat intake should be 20-35% of our total calories.
- Cholesterol should be no more than 300 mg a day.
- For Americans, 33% of calories come from fats, 13% of those come from saturated fats, and 180-320 mg of cholesterol is eaten a day.
- Consume more fish or fish oil supplements to get omega 3.
- Americans consume about 7% of their calories from polyunsaturated fats, a maximum of 10% is recommended.