Chapter 5Nutrition

1Copyright © 2015 McGraw-Hill Education. All rights reserved. No reproduction or distribution without the prior written consent of McGraw-Hill Education.

Understanding Nutritional Guidelines

• Dietary Reference Intakes (DRIs): umbrella term for four sets of dietary recommendations– Suggested intake levels of essential nutrients for

optimal health • Recommended Dietary Allowance (RDA):

represents the average daily amount of any one nutrient to protect against nutritional deficiency

• Acceptable Macronutrient Distribution Range (AMDR): intake levels of essential nutrients that provide adequate nutrition and reduce risk of chronic disease

2Copyright © 2015 McGraw-Hill Education. All rights reserved. No reproduction or distribution without the prior written consent of McGraw-Hill Education.

Understanding Nutritional Guidelines

• Dietary Guidelines for Americans: scientifically based diet and exercise recommendations

• USDA MyPlate: graphic nutritional tool that translates DRIs and Dietary Guidelines into healthy food choices

• Daily Values: standards used on food labels to indicate how a particular food contributes to the recommended daily intake of major nutrients in a 2,000-calorie diet

3Copyright © 2015 McGraw-Hill Education. All rights reserved. No reproduction or distribution without the prior written consent of McGraw-Hill Education.

Types of Nutrients• Essential nutrients: needed to build,

maintain, and repair tissues and regulate body functions

• Macronutrients: needed in large amounts– Water, carbohydrates, proteins, fats

• Micronutrients: needed in small amounts– Vitamins, minerals

4Copyright © 2015 McGraw-Hill Education. All rights reserved. No reproduction or distribution without the prior written consent of McGraw-Hill Education.

Water—The Unappreciated Nutrient

• Function:– Digests, absorbs, transports nutrients– Helps regulate body temperature– Carries waste out of the body– Lubricates our body parts

• Fluid balance: right amount of fluid inside and outside each cell; maintained by electrolytes

5Copyright © 2015 McGraw-Hill Education. All rights reserved. No reproduction or distribution without the prior written consent of McGraw-Hill Education.

Water—The Unappreciated Nutrient

• In most places in U.S. tap water is of equal or superior quality to bottled water

• RDA:– 1 to 1.5 milliliters per calorie spent– 2 to 3 liters, or 8 to 12 cups of fluid– Water needs can vary depending on several

factors, such as foods consumed and activity level

6Copyright © 2015 McGraw-Hill Education. All rights reserved. No reproduction or distribution without the prior written consent of McGraw-Hill Education.

Carbohydrates—Your Body’s Fuel

– The body’s main source of energy– Fuel most of the body’s cells during daily activities– Used by muscle cells during high-intensity exercise– Only source of energy for brain cells, red-blood

cells, and some other types of cells

• Types:– Simple carbohydrates (sugars)– Complex carbohydrates (starches and dietary

fibers)

• RDA:– 130 grams for males and females (aged 1–70)

7Copyright © 2015 McGraw-Hill Education. All rights reserved. No reproduction or distribution without the prior written consent of McGraw-Hill Education.

Simple and Complex Carbohydrates

• Simple carbohydrates:– Easily digestible and composed of one or two units

of sugar• Glucose, fructose, galactose, lactose, maltose,

sucrose

• Glucose travels to liver where it can be stored as glycogen for future energy needs

• Too many simple carbohydrates leaves you with a “sugar high”, followed by a feeling of depletion, and a craving for more sugar– Added sugars have even more dramatic effect– High fructose corn syrup (HFCS)

• Artificial sweeteners touted as alternative– Safety concerns; effect on appetite and insulin

8Copyright © 2015 McGraw-Hill Education. All rights reserved. No reproduction or distribution without the prior written consent of McGraw-Hill Education.

Simple and Complex Carbohydrates

• Complex carbohydrates:– Composed of multiple sugar units including

starches and dietary fiber– Sources:

• Whole grains (whole wheat, brown rice, oatmeal, corn)

• Vegetables; some fruit

– Whole grains preferred over refined carbohydrates (white flour products)

• Provide more nutrients• Slow digestive process• Make you feel full longer

9Copyright © 2015 McGraw-Hill Education. All rights reserved. No reproduction or distribution without the prior written consent of McGraw-Hill Education.

Fiber• Dietary fiber: complex carbohydrate found in

plants that cannot be broken down by the digestive tract

• Fiber allows for passage of food quickly through the intestines, which helps prevent hemorrhoids and constipation

• Soluble fiber dissolves in water and lowers cholesterol

• Insoluble fiber passes through digestive tract unchanged; serves as natural laxative

10Copyright © 2015 McGraw-Hill Education. All rights reserved. No reproduction or distribution without the prior written consent of McGraw-Hill Education.

Fiber• RDA:

– 25 grams/day for women (aged 19-50)– 38 grams/day for men (aged 14-50)

• Fiber is best obtained through diet, not pills or supplements

• Sources of fiber:– Fruits– Vegetables– Dried beans– Peas and other legumes– Cereals– Grains– Nuts– Seeds

11Copyright © 2015 McGraw-Hill Education. All rights reserved. No reproduction or distribution without the prior written consent of McGraw-Hill Education.

Protein—Nutritional Muscle

• Function:– Build and maintain muscles, bones, and other

body tissues– Form enzymes that facilitate chemical reactions– Constructed from 20 different amino acids

• Essential amino acids must be supplied by foods

• Types:– Complete proteins– Incomplete proteins

• RDA:– 0.36 grams per pound of body weight

12Copyright © 2015 McGraw-Hill Education. All rights reserved. No reproduction or distribution without the prior written consent of McGraw-Hill Education.

Protein—Nutritional Muscle

• Complete protein sources– Animal proteins: meat, fish, poultry, milk, cheese,

eggs

• Incomplete protein sources– Vegetable proteins: grains, legumes, nuts, seeds,

other vegetables

• Complementary proteins: proteins that in combination provide essential amino acids

• Mutual supplementation: nutritional strategy of combining two incomplete protein sources to provide a complete protein– For example, beans and rice

13Copyright © 2015 McGraw-Hill Education. All rights reserved. No reproduction or distribution without the prior written consent of McGraw-Hill Education.

Fats—A Necessary Nutrient

• Principal form of stored energy in the body– Provide essential fatty acids– Role in the production of other fatty acids and

Vitamin D– Provide the major material for cell membranes and

for the myelin sheaths that surround nerve fibers– Assist in absorption of fat-soluble vitamins– Affect texture, taste, and smell of foods– Provide emergency reserve when we are sick or

when our food intake is diminished• RDA:

– 20–35% of calories from fat with only about one-third coming from saturated fats

14Copyright © 2015 McGraw-Hill Education. All rights reserved. No reproduction or distribution without the prior written consent of McGraw-Hill Education.

Types of Fat• Saturated fat: found in animal products and

other fats that remain solid at room temperature– Beef– Pork – Poultry– Whole-milk dairy products– Certain tropical oils (coconut and palm)– Certain nuts (macadamia)

15Copyright © 2015 McGraw-Hill Education. All rights reserved. No reproduction or distribution without the prior written consent of McGraw-Hill Education.

Types of Fat• Monounsaturated fat: found primarily in

plant sources, are liquid at room temperature, and are semisolid or solid when refrigerated– Olive, safflower, peanut and canola oils– Avocados– Many nuts

• Polyunsaturated fat: commonly referred to as “oil”; liquid at room temperature and when refrigerated– Corn and soybean oils– Fish, including trout, salmon, and anchovies

16Copyright © 2015 McGraw-Hill Education. All rights reserved. No reproduction or distribution without the prior written consent of McGraw-Hill Education.

Cholesterol• A waxy substance that is needed for several

important body functions• The body produces it from the liver and

obtains it from animal food sources (meat, cheese, eggs, milk)

• Too much cholesterol can clog arteries and lead to cardiovascular disease

• LDLs (low density lipoproteins) are the “bad” cholesterol, while HDLs (high density lipoproteins) are considered “good”

• Recommended: consume no more than 300 milligrams per day

17Copyright © 2015 McGraw-Hill Education. All rights reserved. No reproduction or distribution without the prior written consent of McGraw-Hill Education.

Trans Fats• Liquid vegetable oils that have been

chemically changed through the process of hydrogenation to extend the shelf life of processed foods

• Pose a risk to cardiovascular health by raising LDL levels and lowering HDL levels

• Foods high in trans fatty acids include:– Crackers, cookies, chips– Cakes and pies– Doughnuts– Deep fried foods like French fries

18Copyright © 2015 McGraw-Hill Education. All rights reserved. No reproduction or distribution without the prior written consent of McGraw-Hill Education.

Omega-3 and Omega-6 Fatty Acids

• Omega-3s: contain alpha-linolenic acid, which helps slow the clotting of blood, improves arterial health, and lowers blood pressure

• Omega-6s: contain linolenic-acid and are important to health, though they are often consumed too much by Americans

19Copyright © 2015 McGraw-Hill Education. All rights reserved. No reproduction or distribution without the prior written consent of McGraw-Hill Education.

Minerals—A Need for Balance

• Minerals are naturally occurring substances needed by the body in small amounts– Build strong bones and teeth, and help carry out

metabolic processes and body functions• The body needs 20 essential minerals

– Macrominerals (need at least 100 mgs/day) • Calcium, chloride, magnesium, phosphorous,

potassium, sodium– Microminerals (need less than 100 mgs/day)

• Chromium, cobalt, copper, fluorine, iodine, iron, zinc, manganese, nickel, and others

• A balanced diet provides all the essential minerals the body needs per day

20Copyright © 2015 McGraw-Hill Education. All rights reserved. No reproduction or distribution without the prior written consent of McGraw-Hill Education.

Vitamins—Small But Potent Nutrients

• Naturally occurring organic substances needed by the body in small amounts

• Serve as catalysts for releasing energy from carbohydrates, proteins, and fats while maintaining other body components

• Your body needs at least 11 specific vitamins – A, C, D, E, K, and the B-complex vitamins

• Vitamins can be found in a variety of foods, so often supplements are unnecessary

21Copyright © 2015 McGraw-Hill Education. All rights reserved. No reproduction or distribution without the prior written consent of McGraw-Hill Education.

Key Vitamins and Minerals

22Copyright © 2015 McGraw-Hill Education. All rights reserved. No reproduction or distribution without the prior written consent of McGraw-Hill Education.

Overview of RDIs

23Copyright © 2015 McGraw-Hill Education. All rights reserved. No reproduction or distribution without the prior written consent of McGraw-Hill Education.

Other Substances in Food: Phytochemicals

• Phytochemicals: substances naturally produced by plants

• May keep cells healthy, slow tissue degeneration, prevent carcinogens, reduce cholesterol, protect heart, maintain hormone levels, keep bones strong

• Three important types of phytochemicals:– Antioxidants: neutralize free radicals– Phytoestrogens: lower cholesterol and reduce

risk of heart disease– Phytonutraceuticals: may inhibit growth of cancer

and heart disease

24Copyright © 2015 McGraw-Hill Education. All rights reserved. No reproduction or distribution without the prior written consent of McGraw-Hill Education.

The Color Wheel of Foods

25Copyright © 2015 McGraw-Hill Education. All rights reserved. No reproduction or distribution without the prior written consent of McGraw-Hill Education.

Dietary Guidelines for Americans

• Two-thirds of Americans are now overweight or obese

• Focus is on stopping and reversing the spread of overweight and obesity

• Approaches to change:– Individual– Environmental– Food supply

26Copyright © 2015 McGraw-Hill Education. All rights reserved. No reproduction or distribution without the prior written consent of McGraw-Hill Education.

Dietary Guidelines for Americans

• Four main goals:– Reduce calorie intake and increase physical

activity – Move toward a more plant-based diet composed

of nutrient-dense foods– Reduce intake of foods containing added sugars

and solid fats and reduce overall sodium and refined grain consumption

– Meet the 2008 Physical Activity Guidelines provided by the U.S. Department of Health and Human Services

27Copyright © 2015 McGraw-Hill Education. All rights reserved. No reproduction or distribution without the prior written consent of McGraw-Hill Education.

2010 Dietary Guidelines for Americans: Key Messages

28Copyright © 2015 McGraw-Hill Education. All rights reserved. No reproduction or distribution without the prior written consent of McGraw-Hill Education.

Dietary Guidelines for Americans

• MyPlate: visual icon designed to raise awareness and health literacy about the different food groups– Emphasize foods high in nutrient density

• Individual calorie requirements are calculated based on sex and age at three activity levels:– Sedentary: only light physical activity– Moderately active: equivalent to walking 1.5 miles

per day at 3–4 mph– Active: more than 3 miles per day at 3–4 mph

29Copyright © 2015 McGraw-Hill Education. All rights reserved. No reproduction or distribution without the prior written consent of McGraw-Hill Education.

MyPlate

30Copyright © 2015 McGraw-Hill Education. All rights reserved. No reproduction or distribution without the prior written consent of McGraw-Hill Education.

Estimated Calorie Requirements

31Copyright © 2015 McGraw-Hill Education. All rights reserved. No reproduction or distribution without the prior written consent of McGraw-Hill Education.

Dietary Guidelines for Americans

• DASH Eating Plan: Dietary Approaches to Stop Hypertension

• Recommendations for specific groups– Children and adolescents– Older adults– Pregnant and breastfeeding women– Overweight adults and children– People with chronic conditions

• Limit red meat consumption– Link to heart disease, cancer, and diabetes

32Copyright © 2015 McGraw-Hill Education. All rights reserved. No reproduction or distribution without the prior written consent of McGraw-Hill Education.

Vegetarian Diets

• Vegetarian diets may offer protection against obesity, heart disease, high blood pressure, diabetes, digestive disorders, and some forms of cancer

• Vegetarians need to make sure their diets provide the energy intake and food diversity necessary to meet dietary guidelines

33Copyright © 2015 McGraw-Hill Education. All rights reserved. No reproduction or distribution without the prior written consent of McGraw-Hill Education.

Daily Values on Food Labels

• FDA regulates food labels– List serving size and number of servings– Give total calories and calories from fat

• Look for foods with no more than 30 percent of their calories from fat

– Show how much the food contributes to Daily Values for important nutrients

– Shows % of Daily Value: recommended daily intake of specified nutrients

34Copyright © 2015 McGraw-Hill Education. All rights reserved. No reproduction or distribution without the prior written consent of McGraw-Hill Education.

Nutrition Facts Food Label

35Copyright © 2015 McGraw-Hill Education. All rights reserved. No reproduction or distribution without the prior written consent of McGraw-Hill Education.

Front-of-Package Food Labels

• FDA’s authority to regulate health claims on front-of-package (FOP) food labels is limited– Institute of Medicine found these labels provide

little guidance and cause confusion• 12 different symbols, logos, and icons

– Recommended a standard for FOP labels

36Copyright © 2015 McGraw-Hill Education. All rights reserved. No reproduction or distribution without the prior written consent of McGraw-Hill Education.

Recommended FOP Labels

37Copyright © 2015 McGraw-Hill Education. All rights reserved. No reproduction or distribution without the prior written consent of McGraw-Hill Education.

Proposed Changes to the Nutrition Facts Label

• 2014 proposed changes to Nutrition Facts label for packaged food– Mandated inclusion of information on added

sugars– Updated reference amounts– Specified calorie and nutrition information based

on whole package not just serving size– Information on potassium and vitamin D in

packaged food required– Altered label format to emphasize calories,

serving size, and Percent Daily value

38Copyright © 2015 McGraw-Hill Education. All rights reserved. No reproduction or distribution without the prior written consent of McGraw-Hill Education.

Restaurant Menu Labels• 2010 Patient Protection and Affordable Care

Act includes new requirement: all chain restaurants provide calorie labeling on their menus

• Preliminary research suggests consumers are no more likely to choose healthier menu items

39Copyright © 2015 McGraw-Hill Education. All rights reserved. No reproduction or distribution without the prior written consent of McGraw-Hill Education.

Current Consumer Concerns

• Overconsumption of soft drinks• High-sodium diets• Food allergies and food intolerances

– Eight foods responsible for 90% of allergies: milk, eggs, peanuts, tree nuts, shellfish, soy, and wheat

– Food intolerances such as lactose intolerance are less severe

• Gluten-free diets– Celiac disease: immune reaction to gluten which

is found in wheat, barley, rye, and triticale• Overconsumption of energy bars and

energy drinks

40Copyright © 2015 McGraw-Hill Education. All rights reserved. No reproduction or distribution without the prior written consent of McGraw-Hill Education.

Current Consumer Concerns

• Probiotics, prebiotics, and synbiotics – Probiotics are living bacteria that may aid

digestion; prebiotics are nondigestible carbohydrates that fuel probiotics

– Synbiotics combine the two– Scientific studies have not confirmed health

benefits• Fast foods• Food deserts: low-income areas where

more than 500 people or 33% have low access to a supermarket– When fresh produce not available, people don’t

have opportunity to choose a healthy diet

41Copyright © 2015 McGraw-Hill Education. All rights reserved. No reproduction or distribution without the prior written consent of McGraw-Hill Education.

Fast-Food Meal

42Copyright © 2015 McGraw-Hill Education. All rights reserved. No reproduction or distribution without the prior written consent of McGraw-Hill Education.

Organic Foods• Plant foods grown without synthetic pesticides

or fertilizers• Animal foods raised on organic feed without

antibiotics or growth hormone• USDA regulates labeling• Research has not demonstrated health

benefits, but environmental benefits are clear– Look for foods that are not only organic but also

locally grown– Wash organic produce thoroughly

43Copyright © 2015 McGraw-Hill Education. All rights reserved. No reproduction or distribution without the prior written consent of McGraw-Hill Education.

Foodborne Illnesses• Food intoxication: food poisoning in which

food is contaminated by natural toxins– Botulism

• Food infection: food poisoning in which food is contaminated by disease-causing microorganisms, or pathogens– E. coli, salmonella, campylobacter– Pet food can contain salmonella

• Use safe food practices and store food safely, especially leftovers

44Copyright © 2015 McGraw-Hill Education. All rights reserved. No reproduction or distribution without the prior written consent of McGraw-Hill Education.

Kitchen Safety

45Copyright © 2015 McGraw-Hill Education. All rights reserved. No reproduction or distribution without the prior written consent of McGraw-Hill Education.

Genetically Modified Foods

• Genetically modified (GM) organisms: genetic makeup has been changed to produce desirable results– Selective breeding– Modern biotechnology faster and more refined

• Many crops are already GM• Sixty percent of processed foods in

supermarkets contain one or more GM ingredient

• Safety assessed by FDA’s Center for Food Safety and Applied Nutrition (CFSAN)

46Copyright © 2015 McGraw-Hill Education. All rights reserved. No reproduction or distribution without the prior written consent of McGraw-Hill Education.