Choosing a Nutritious DietChapter 5

Objectives

List several factors that influence dietary choices

Describe the dietary guidelines proposed by the US government and health organizations

Describe the US industrial food production system

Describe the ingredients and nutrition facts on labels on manufactured foods

Describe the 3 functions of food

List the 3 functions of biological energy

List the 7 components of food, and identify common foods that contain each component

Describe the 3 kinds of vegetarian diets and several reasons for vegetarianism.

“

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The destiny of a nation depends on the manner in which it feeds itself

Jean Anthelme Brillat-Savarin (1775-1826)

Organizations that Establish Guidelines for Eating

W.H.O – World Health Organization

AHA – American Heart Association

ACS – American Cancer Society

USDA – US Dept. of Agriculture

Guidelines released every 5 years

My Plate

MyPlate

A graphic design divided into 4 sections on a plate for fruits, veggies, protein, and grains with a dairy cup beside it.

Intended to encourage consumers to

Enjoy food, but avoid oversized portions

Make nearly ½ the plate fruits & veggies of all colors

Make at least ½ the grain, WHOLE grains

Consume 1-2 servings of fat free or low fat milk

Drink water instead of sugary drinks

Choose packaged and frozen food items that contain less salt/sodium.

Limit red meat, bacon, cold cuts & other processed meats

Types of Diets

DASH diet

(dietary approaches to stop hypertension)

Traditional Asian/Mediterranean diets

based on unprocessed grains, beans, fresh veggies/ fruits & fish

associated with less heart disease and cancer

Common American diet

based on meats, refined flour products and industrial foods such as fast food, packaged foods, snacks and seeds

Associated with higher incidence of heart disease, obesity, cancer, overweight

Factors that influence food consumption choices

Knowledge of healthy nutrition

Family ethnic & cultural eating patterns

Social factors ( eating what friends eat)

Food fads

Time pressures that limit thoughtful food shopping & meal prep

Stress

Marketing & advertising

Cost & availability

The US food supply contains an abundance of inexpensive foods that contain considerable calories but are low in nutritional quality

15% of US families whose incomes are so low that they risk going hungry (food insecurity), tend to consume calories from the least nutritious foods available.

Terms to know

Calorie dense

Nutritionally dense

Food that contain considerable calories, but little nutritional value

Food that is high in nutrition in proportion to their calorie content

US food production & distribution system

$2 trillion a year US food industry contributes 13% to the GDP

Employs 17% of Americans

Has become increasingly efficient over the last 100 years-

Less $ goes to farmers & more $ goes to food processing & distribution

Less farms produce a variety of crops

More farms produce single crops (soybeans, corn, wheat or rice) used to manufacture inexpensive packaged food & fuels & feed for beef, dairy, cows, etc.)

US food production & distribution system disadvantages

The further the distance between the farmer and the consumer, the greater the Economic & political advantages may be exerted over the consumer

Cost of energy (financial & environmental) for food manufacturing & distribution (fossil fuel consumption)

Products shipped from other countries may not be inspected for bacteria and toxic chemicals, increasing foodborne illness risk

Does not provide the healthiest & safest foods

- Fast & processed foods major continuer to heart disease, type 2 diabetes, high bp, cancers

Terms to know

Ingredients label

Nutrition food label

Percent Daily Value (PDV)

lists the ingredients in descending order by weight on manufactured food

Lists the quantity of certain nutrients in the food and the % daily value for those nutrients for a manufactured food

% of the RDA (recommended daily amount) of a particular nutrient found in a food

3 functions of food

To provide chemical constituents of the body

To provide the energy for life

To be pleasurable

(appealing in smell, taste, sight , texture)

Associated with enjoyable social activities

Satisfy hunger

Energy is needed to support 3 major processes

Basal Metabolism

The energy needs of the body just to keep it alive

BMR – basal metabolic rate a.k.a. RMR - resting metabolic rate

About 1,100 calories/day for women

About 1,300 calories/day for men

Physical activity

Walking, working ,etc.

Caloric needs dependent upon intensity, time, body’s size, environmental temp.

Growth & Repair

Puberty, pregnancy, infancy, breastfeeding recovery from injury times have greater caloric needs than senior citizens

Estimate your daily caloric needs step by step

1. What is your height? _____feet ____inches

2. How many body mass units do you have? ____________total body mass units

a. Women: allow 100 body mass units for the first 5 feet of height + 5 body mass units for each additional inch

b. Men: allow 106 body mass units for the first 5 feet of height & 6 body mass units for each additional inch

3. What is your activity factor?

Sedentary = 13 Active =15 Very Active = 17

4. What is your estimated daily calorie need? ______________calories/day

a. Multiply your body mass units by your activity factor

Weight Management

People interested in weight management should keep in mind that a large percentage of energy is required just to stay alive.

Cutting back on food alone is a limited and generally unsuccessful strategy.

Increasing physical activity output will consume energy without affecting basic life functions

7 chemical components of food

Proteins

Carbohydrates

Lipids (fats)

Vitamins

Minerals

Phytochemicals

water

Foundations of every cell, composed of amino acid chains

Most economical & efficient energy source; consists of 1 or more sugar molecules

Fats such as cholesterol & Essential organic substance needed daily in small amounts to perform specific functions in the body

Inorganic elements found in the body both in combination with organic compounds & alone

Chemicals produced by plants

triglycerides principal constituent of blood and the major component of all cells

Proteins

Yields 4 calories/gram

Made up of amino acids: essential & non-essential

Adults needs 8 essential amino acids

Infants needs 8 essential amino acids + 2 more

The body can transform essential amino acids to non-essential amino acids as needed.

Complete Food sources: milk/milk products, meat, fish, poultry & eggs

Incomplete food sources: breads, cereal products, legumes, nuts, seeds

Food should be paired with complete proteins to reduce amino acid deficiency

Lipids (fats)

Yields 9 calories/gram

Provide flavor & texture to food

Digesting fats provide feelings of satiety & well being

Diets high in cholesterol & saturated fat increase risk of heart disease, some cancers & obesity.

Trans fatty acids (partially hydrogenated vegetable oils) are unhealthy and are being removed from packaged food products

Artificial fats: (Olestra, Simplesse) chemicals that are added to packaged foods for taste without calories

Carbohydrates

Yields 4 calories/gram

Diets low in carbs force the body to break down muscle tissue to supply energy for life functions

2 types of carbs:

simple sugars – found in fruit

complex carbs – found in grains, fruit and vegetable stems, leaves, and roots

2 main classes of complex carbs: starch (digestible) & fiber (not digestible)

2 kinds of fiber: soluble and insoluble ( cannot dissolve in water)

Sugars:

Fructose ; very sweet, found in honey & fruit ; HFC (high fructose corn syrup) added to commercial food products

Sucrose; common table sugar

Lactose; found in dairy products – made up of glucose & galactose

Vitamins

Classifieds as water soluble or fat soluble vitamins (A,D,E,K)

Needed to assist in body functions

Vitamins A,C,E = antioxidant vitamins b/c they neutralize the free radicals which can damage cell structures though oxidation.

Folic Acid (aka folate/folacin) found in dark green leafy veggies, beans and fruits help prevent neural tube defects & reduce homocysteine levels in the blood (related to risk of heart disease)

Minerals

Inorganic elements needed for maintaining cell membranes, conducting nerve impulses and contracting muscles

Found in almost all food

Phytochemicals

Chemical substances found in foods that are not nutrients but positively affect human physiology by destroying and eliminating toxins from the environments or free radicals.

Food Sources: broccoli, kale, cauliflower, tomatoes, pink grapefruit, watermelon, green & black tea

Water

Body water is maintained at constant levels by the nervous, hormone & urinary systems.

The average adults loses about 8 glasses of water/day through sweat, moisture in air, urine and feces.

Reasons to choose vegetarian diets

Avoid killing animals

Contribute to efficient utilization of world protein supplies

Live longer & healthier lives

vegetarians have lower rates of coronary heart disease, high bp, diabetes, obesity & cancer

Types of vegetarianism

Strict vegetarian aka veganism –

Lacto-vegetarianism –

Lacto-ovo vegetarianism –

Excludes all animal products including meat ,cheese, egg & dairy

excludes meat, poultry fish & eggs but includes dairy products

excludes meat, poultry and seafood but includes eggs & dairy

Review 1

The US Gov’t & health organizations have created dietary guidelines to help people make nutritional choices to prevent heart disease, cancer, & other diseases based on the consumption of whole grains, fruits & vegetables; while limiting the consumption of meats, whole fat dairy products, salt and fatty, sugary snacks and sweets

The US food production & distribution systems are highly industrialized and have significant effects on the environment, health and food security.

My Plate emphasizes the consumption of polyunsaturated fats, fruits, and veggies rather than refined grain products, meats & sweets.

The ingredients label on a food product lists the components of the product in descending order by weight

Review 2

The nutrition facts label provides information on the amounts of certain nutrients in a food product.

Food has 3 functions: to provide chemical constituents of the body, energy, and pleasure.

Food is composed of 7 components: protein, carbohydrate, fat water, vitamins, minerals and phytochemicals

Dietary supplements are unregulated substances that are used to augment the nutritional adequacy of the diet and as drugs to heal or prevent illness.

Manufactured foods contain a variety of additives that alter their texture, flavor color, and stability. Preservatives keep foods from spoiling through the use of sulfites.

Review 3

One nonchemical method of food preservation involves exposing food to gamma irradiation to destroy microorganisms.

Artificial sweeteners are widely used, most commonly in diet soft drinks.

There are several reasons for being a vegetarian, including increased interest in health, ecology, and world issues; economical issues; and the philosophy of not killing animals.

A strict vegetarian, or vegan diet eliminates all animal products, including milk, cheese, eggs and other dairy products.