Nutrition Chapter 9

Essential Nutrients There are 45 essential nutrients

These cannot be manufactured by the body and must come from food source.

MacronutrientsProtein, Fats, Carbohydrates, and Water

MicronutrientsVitamins and Minerals extracted during

digestion

Energy from Nutrients

PROTEINS 4 CALORIES/GRAMCARBOHYDRATES 4 CALORIES/GRAMFAT 9 CALORIES/GRAM(ALCOHOL) 7 CALORIES/GRAM

PROTEINProteins are made up of building blocks called amino acids. Nine amino acids are essential – the rest can be manufactured by the body if the essential amino acids are present.Complete Proteins contain all 9 essential amino acids.Incomplete Proteins do not have all essential amino acids – some vegetables and legumes are incomplete and therefore, most be combined with other protein sources to get all 9 essential proteins.

RDI .36 grams/lb. 50g for 140 lb. person 10 - 35% of total caloric intake should be from protein

FATSTwo essential fats (aka lipids):

Linoleic acid and alpha-linolenic acid (polyunsaturated)

Triglyceride is a molecule of glycerol (an alcohol) plus three fatty acid chains. The type of fatty acid chain determines whether it is:

unsaturatedmonounsaturatedpolyunsaturatedsaturated

Omega - 6 Omega - 3

FATSSaturated fats are usually solid at room

temperatureLeading saturated fats are red meat, whole milk,

cheese, lunch meats (many from animal products)

Mono – and Polyunsaturated fats are usually liquids at room temperature and derived from plant products

Hydrogenation Process used to improve stability and improve the shelf life of unsaturated oils. Results in more saturated and trans fatty acids

GOOD AND BAD FATSHealth effects of different types of fat:Trans fatty Acids and Saturated fats are thought to adversely effect: Heart healthCancer risk (some cancers)Weight ManagementUnsaturated fat: 20 – 35% of total daily calories

CholesterolWaxy substance in blood needed for synthesis of cell

membranes, vitamin D, and hormonesThere are two types of blood fat that work differently in the body:Low Density Lipoproteins (LDL) (bad cholesterol)

transports cholesterol to organs and tissues excess deposits on artery walls – thought to be bad for heart healthHigh Density Lipoproteins (HDL) (good cholesterol)

transports cholesterol out of arteries – thought be good for heart health

Trans – and Unsaturated Fats

Heart Health Effects:

Increases amount of LDL cholesterol in blood results in LDL build up on artery walls

May increase risk for certain types of cancer (i.e. colon)

Good and Bad FATSGOOD FATS

Mono unsaturated fats

Olive OilCanola OilSafflower OilPeanut Oil (& other nuts)Poly unsaturated fats

Soybean OilCorn OilCottonseed OilsFish Oils

BAD FATSSaturated fats

Palm OilCoconut OilStick MargarineButterCheeseAnimal Fats (fat and skin)Trans fatty Acids

Food fried in vegetable oils

RDI for FATS

Fat Intake:20 – 35% of total calories/dayMen

17 g/day of linoleic acid1.6 g/day of alpha-linolenic acid

Women12 g/day of linoleic acid1.1 g/day of alpha-linolenic acid

This is about 3 – 4 teaspoons (25-20 g)/day of vegetable oil.

Carbohydrates

Supply energy for body cells and some cells use carbohydrates exclusively (some parts of brain, nervous system, muscles and blood)

High energy exercise uses carbohydrates for fuel.

CarbohydratesSimple Carbohydrates

Sugars such as sucrose, fructose, lactose

Add sweetness to food.

Glucose is a simple sugar that is broken down from ingested carbohydrates during digestion.

It is stored in the liver and muscles as glycogen

Complex Carbohydrates

Starches and Dietary Fiber

Includes wheat, rye, rice, oats, barley, millet, legumes (dry beans, peas, lentils and tubers (potatoes & yams)

CarbohydratesRefined or Processed Carbs have all the calories, but the fiber, some

vitamins are removed when the inner and outer layers are removed during processing leaving only the starchy middle layer

White Bread, White Rice are examples of Processed Carbohydrates

Whole Grain Carbohydrates

Are unrefined and no layers are stripped away.Have higher fiber contentMore vitamins and minerals and other vital

compoundsDon’t spike the glycemic index because the

fiber slows down its absorption and enter the bloodstream more slowly.

45 – 65% of total intake of calories

FiberNon digestible part of carbohydrates that are

important for digestive tract health.Dietary Fiber non digestible fiber that is

naturally present in carbohydrates such as grains, legumes and vegetables

Functional Fiber synthesized non digestible fiber added to food as a supplement

Total FiberDietary and Functional Fiber total content of a

carbohydrateSoluble Fiber (Oat Bran, Legumes)Delays stomach emptying, slows movement of glucose into the blood after eating, reduces cholesterol Insoluble Fiber (Wheat Bran, Psyllium)Increases fecal bulk, prevents constipation, helps reduce type 2 diabetes, heart disease, and pulmonary disease. Good for gastrointestinal health and weight management

Vitamins Organic Micronutrients

Organic carbon containing substances required in small amounts to regulate various processes within living cells. Help regulate chemical reactions

Humans need 13 vitamins:Vitamins: A,D,E,K (fat soluble)9 vitamins that arewater soluble:C, B complex: thiamin, riboflavin, niacin, B-6,

folate, vitamin B-12, biotin, and pantothenic acid

Function of VitaminsCritical to production of red blood cellsCritical to maintenance of nervous, skeletal, and immune

systemsSome act as antioxidants – preserve cell overall health (key

ones are E, C, A precursor beta carotene (converts to vitamin A)

Antioxidants lessen the breakdown of food or body constituents by free radicals such as binding oxygen, donating electrons to free radicals and repairing damage to molecules

Most vitamins are not produced in the body

MineralsInorganic Micronutrients

Necessary in small amounts for growth, regulation, and maintenance of body tissues and functions and help release energy

There are 17 essential minerals:Major minerals:Calcium, phosphorus, magnesium, sodium,

potassium and chloride

Major Trace ElementsNeed minute amounts of trace elements but

they are considered essentialMajor Trace Elements

Copper, Fluoride, Iodide, Iron, Selenium, Zinc

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USDA’S MyPyramid

MyPyramid: Number of Daily Servings and Serving

SizesGrains (6): 1 slice of bread, 1 small muffin

(2.5” diameter), 1 cup ready-to-eat cereal flakes, ½ cup cooked cereal, 1 (6”) tortilla

Vegetables (5): ½ cup cooked or raw vegetables, 1 cup raw leafy salad greens,½ cup of vegetable juice

Fruit (4): ½ cup fresh/canned/frozen fruit, ½ cup 100% fruit juice, 1 small whole fruit, ¼ cup dried fruit

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Milk/Dairy (3): 1 cup milk or yogurt, ½ cup ricotta cheese, 1½ oz. natural cheese, 2 oz. processed cheese

Meat and Beans (5½): 1 oz. cooked lean meat/poultry/fish, ¼ cup cooked dry beans or tofu, 1 egg, 1 tablespoon peanut butter, ½ oz. nuts or seeds

Oils (6 teaspoons per day)Discretionary calories,

solid fats, and added sugars

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MyPyramid: Number of Daily Servings and Serving

Sizes

Phytochemicals and AntioxidantsWhen the body uses oxygen or breaks down

certain fats or proteins during normal metabolism it can give rise to free radicals that are unstable molecules that react with fats, proteins and DNA damaging cell membranes and mutating genes.

Implicated in cancer, aging, CV disease and degenerative diseases like arthritis.

Antioxidants and phytochemicals are thought to reduce formation of free radicals, remove them from the body, or repair them.

Other ConsiderationsRefined sugar

Cholesterol

Sodium