Sources of Nutrition (Nutrition Ch 1) Flashcards Preview

ATI-Review Modules > Sources of Nutrition (Nutrition Ch 1) > Flashcards

Flashcards in Sources of Nutrition (Nutrition Ch 1) Deck (54)
Loading flashcards...


-organic compounds composed of carbon, hydrogen, and oxygen (CHO)
-main function: provide energy for the body
-ave. min. amount to fuel the brain = 130 g/day
-median intake for men = 200-330 g/day
-median intake for women = 180-230 g/day
-acceptable macronutrient distribution range for carbs is 45-65% of calories
*provide energy for cellular work and help regulate protein and fat metabolism
*essential for normal cardiac and CNS functioning
*provide 4 cal/g of energy


3 types of carbohydrates

*classified according to # of saccharide units making up their structure
1) monosaccharides: simple carbs (glucose, fructose)
2) disaccharides: simple carbs (sucrose, lactose)
3) polysaccharides: complex carbs (starch, fiber, glycogen)


Complex carbohydrates

-as they are ingested and broken down, they are easily absorbed in the intestine and bloodstream where they are stored in the liver and muscles for energy needs.



-the stored carbohydrate energy source found in the liver and muscles.
-vital source of backup energy



-categorized as carbohydrate, but does not yield energy for the body
-it is the substance in plant foods that is indigestible (pectin, gum, cellulose, and mucilage)
-important for proper bowel elimination--adds bulk to feces and stimulates peristalsis to ease elimination



-glucose (corn syrup)
-fructose (fruits)
-galactose (milk sugar broken down)

*basic energy for cells



-sucrose (table sugar, molasses)
-lactose (milk sugar)
-maltose (sweeteners)

*energy, aids calcium and phosphorus absorption (lactose)



-starches (grains, legumes, root vegetables)
-fiber (indigestible plant parts)

*energy storage (starches), digestive aid (fiber)



-provided by plant and animal sources
-formed by linking amino acids in various combinations for specific use by the body
-many metabolic functions: tissue-building and maintenance, balance of nitrogen and water, backup energy, support of metabolic processes [nitrogen balance, transportation of nutrients, other vital substances], support of immune system
*provide 4 cal/g of energy


3 types of proteins

1) complete: generally obtained from animal sources, contain all 9 essential amino acids
2) incomplete: generally from plants (grains, nuts, legumes, vegetables, fruits), DO NOT contain all the essential amino acids
3) complementary: those food sources, when eaten together, provide all essential amino acids


3 main factors influence the body's requirements for protein:

1) tissue growth needs
2) quality of the dietary protein
3) added needs due to illness


Recommended dietary requirement of protein for adults

-10% of intake, or 46 g/day for women and 56 g/day for men


Lipids (sources)

-dark meat
-poultry skin
-dairy foods
-added oils (margarine, butter, shortening, oils, lard)



-essential nutrient for the body
-serves as concentrated form of energy for body (2nd to carbs)
-supplies important tissue needs (hormone production, structural material for cell walls, protective padding for vital organs, insulation to maintain body temp, covering for nerve fibers, aids in absorption of fat-soluble vitamins)

*no more than 20-35% of total calories should come from fat (10% or less from saturated fat sources)
**exception = children < 2 yrs, need higher amount of fat to develop brain tissue
***provide 9 cal/g of energy


Categories of fat

1) triglycerides
2) phospholipids
3) sterols
4) saturated fats
5) unsaturated fats
6) polyunsaturated fats
7) essential fatty acids



*primary form of fat in food
-combine with glycerol to supply energy to the body
-allow fat-soluble vitamin transport
-form adipose tissue that protects the body



*derived from triglycerides
-important to cell membrane structure


Sterols (cholesterol)

-necessary for cell membrane stability and production of certain hormones and bile salts for digestion
*if consumed in excess, it can build up in tissues and cause congestion, increasing risk of CV disease


Saturated fats

-animal origin


Unsaturated fats

-usually from plant sources
-help reduce health risks (except coconut and palm oil)


Essential fatty acids

-made from broken down fats
-must be supplied by the diet
-omega-3 and omega-6
-used to support blood clotting, blood pressure, inflammatory responses, and many other metabolic processes


Lipid metabolism

-majority occurs after fat reaches small intestine, where the gallbladder secretes concentrated bile and acts as an emulsifier to break fat into smaller particles.
-at the same time, the pancreas secretes pancreatic lipase, which breaks down fat.
-small intestine secretes an enzyme for further breakdown
-muscles, liver, and adipose tissue cause the release of fatty acids
-liver produces lipoproteins to carry lipids


3 types of lipoproteins

1) very-low-density lipoproteins (VLDL): carry triglycerides to the tissues
2) low-density lipoproteins (LDL): carry cholesterol to the tissues
3) high-density lipoproteins (HDL): remove excess cholesterol from the tissues ("good" cholesterol)



-organic substances required for many enzymatic reactions
-main function: to be a catalyst for metabolic functions and chemical reactions
-13 essential vitamins
-yield no usable energy for the body


2 classes of vitamins

1) water-soluble: vitamins C and B-complex
2) fat-soluble: vitamins A, D, E, and K


Vitamin C
(ascorbic acid)

-aids in tissue building and metabolic reactions (wound and fraction healing, collagen formation, adrenaline production, iron absorption, conversion of folic acid, cellular adhesion).
-found in citrus fruits (oranges, lemons), tomatoes, peppers, green leafy vegetables, and strawberries
-stress and illness increase need for vitamin C
-deficiency = scurvy (a hemorrhagic disease w/ diffuse tissue bleeding), decreased iron absorption, bleeding gums


Thiamin (B1)

-necessary for proper digestion, peristalsis, and providing energy to the smooth muscles, glands, the CNS, and blood vessels
-sources = meats, grains, legumes
-deficiency = beriberi, altered digestion, CNS and CV problems


Riboflavin (B2)

-required for growth and tissue healing
-sources = milk, meats, and green leafy vegetables
-deficiency = cheilosis (manifestations include scales and cracks on lips and mouth), smooth/swollen red tongue, and dermatitis particularly in skin folds


Niacin (B3)

-aids in metabolism of fats, glucose, and alcohol
-sources = beef liver, nuts, legumes, whole grain and enriched breads and cereals
-deficiency = pellagra (manifestations include sun-sensitive skin lesions, GI and CNS findings), dementia


Pantothenic acid (B5)

-involved in biological reactions (energy production, catabolism, and synthesis of fatty acids, phospholipids, cholesterol, steroid hormones, the neurotransmitter acetylcholine)
-sources = organ meats (liver, kidney), egg yolk, avocados, cashew nuts and peanuts, brown rice, soy, lentils, broccoli, and milk
-deficiency = anemia and CNS changes
(though unlikely due to the diverse availability in foods)