Choosing a Nutritious Diet

Chapter 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.

“

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.

2.

3.

4.

What is your height? _____feet ____inches 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 What is your activity factor?

Sedentary = 13 Active =15 Very Active = 17 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.