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The of Nutrition in our Health Chapter 1
Why care about nutrition? What are the nutrients in food? What constitutes a nutritious diet?
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PLEASE PONDER . . .
We have shifted from Infectious Disease to Chronic Disease as major cause of death in the United States
Diet can positively or negatively impact chronic disease
Nutrition: the study of food, including
How food nourishes our bodies How food influences our health
Nutrition is a relatively new discipline of science.
Study of nutrients and other substances in foods and the body's handling of them.
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Nutritional Sciences
Immunology Education Medicine
Psychology
Genetics
Nutritional Sciences
Sociology
Biology
Biochemistry
Physiology
Consumption
Excretion
Digestion
Nutrition encompasses the following aspects of food
Storage Absorption
Metabolism
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Psychological
Cultural
Nutrition also studies these aspects of food
Food safety
Global food supply
Why is Nutrition Important?
Nutrition contributes Nutrition contributes to ....... Wellness
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Wellness: more than absence of disease
Active process: Physical, emotional, d i it l h lth and spiritual health
Critical components of wellness:
Nutrition y y Physical activity
Healthful diet can prevent disease
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Pellagra
Obesity is a growing problem.
Obesity rates continued to rise last year in every state but one, and government policies and actions to date offer little hope of countering the trend according to a trend, new report by Trust for America's Health. Approximately 119 million Americans, or 64.5 percent, of adult Americans are either overweight or obese. Estimates of the number of obese American adults rose from 23.7 percent in 2003 to 24.5 percent in 2004. To help combat the obesity crisis, in the report, Some y p y of the key recommended policy action items include: Bolstering Preventive Care Leveraging Change in Food Options Smarter Community Design Improving School Nutrition and Physical Education Providing More Useful Information and Support
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Nutrition is so important it has become a national goal to promote optimal health and disease prevention.
Goals of Healthy People 2010
Increase quality and years of y healthy life Eliminate health disparities
Healthy People 2010
What Are Nutrients?
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Nutrients
Nutrient Categorization
Organic vs. Inorganic
Three Categorizati ons of the six nutrients
Macronutrients vs. Micronutrients
Essential Vs Non-Essential
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Organic vs. Inorganic I i Nutrient
Carbon is key to life Carbon is key to life
An essential component of all living organisms
By definition is present in all organic compounds.
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Organic vs. Inorganic Nutrient
Example of Organic Nutrient C6H12O6 = Glucose
Example of Inorganic E l fI i Nutrient H2O = Water
Organic Compounds vs. Organic Foods
Organic Compounds: Chemically Organic Contain carbon
Organic Foods Organic Foods
"Certified Organic" Grown without pesticides, herbicides, or synthetic growth promoters
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Organic Nutrient Contain Carbon
Carbohydrates
Fats (Lipids)
Proteins
Vitamins
Inorganic Nutrient Do D not contain t t i Carbon
Minerals
Water
Essential Vs Non-Essential
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Essential
Nonessential
MUST be obtained from the diet
Not necessary to obtain from the diet
Required by body Cannot be made in required amounts
Body can make in sufficient amounts
Macronutrient Vs Micronutrient
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Required in large amounts
Macronutrients
(Grams)
Carbohydrates
Fats (Lipids)
Proteins
Water
Micronutrients
(Mg or ug)
Required in small Required in small amounts
Minerals
Vitamins
3 Energy-Yielding Macronutrients
Proteins Carbohydrates Fats (Lipids)
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Energy From Nutrients
Amount of i energy in foods varies
Kilocalorie:
Amount of energy required to raise the temperature of the temperature of 1g of water by 1oC.
On food labels, "Calorie" actually refers to kilocalories.
We measure energy in kilocalories (kcal).
kilocalorie (kcal)) =1000 calories (Calorie)
Carbohydrates
Primary source of fuel for the body, especially for the brain and physical activity.
Carbohydrates
Sources: Grains (wheat, rice), vegetables, fruits, and legumes (lentils, beans, peas), milk beans peas) milk products.
Provide 4 kcal/gm
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Lipids (Fats)
An important energy source energy source during rest or low intensity exercise.
Provide fat soluble soluble vitamins and essential fatty acids.
Dietary fats: butter, margarine, oils.
Stored as Stored as adipose tissue (body fat).
Insoluble in water.
Provide 9 kcal/gm
Proteins
Proteins are important for Proteins are chains of amino acids. of amino acids Proteins are an important source of nitrogen.
Building cells and tissues Maintaining bones Repairing damage Repairing damage Regulating metabolism
Protein sources include meats, dairy products, seeds, products seeds nuts, and legumes.
Provide 4 kcal/gm
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Calculation of Calories from Macronutrients
Nutrient
Carbohydrate
Grams
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Energy
4 kcal/gm
Calories
80
Fat (Lipid)
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9 kcal/gm
270
Protein
10
4 kcal/gm
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Which macronutrients are primarily for energy?
a) Proteins and fats b) Carbohydrates and proteins c) Carbohydrates and fats d) Fats and vitamins
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Carbohydrates and fats serve primarily an energy function: Carbohydrates for quick energy and fat function: Carbohydrates for quick energy and fat for more sustained energy needs. Protein, although it can be used for energy, should not serve this function regularly as it serves many other functions.
Macronutrient Water (H2O)
Essential Nutrient Foremost of the macronutrients Constantly lost y and replaced
Nearly all of the body's activities are body s activities are conducted in water.
Not energy yielding
Inorganic
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MICRONUTRIENTS Vitamins Minerals
Act as regulators and assist in all body processes. Some minerals serve as parts of body structures. Regulator Nutrients DO NOT PRODUCE ENERGY
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13 vitamins
Categorized Based on solubility.
Four Fat Soluble Vitamins A,D,E,K Nine Water Soluble Vitamins B VITAMINS: 8 VITAMIN C: 1
Solubility Characteristics
Determines how they are absorbed Determines how they are transported in the bloodstream Whether they are stored in the body How easily they are lost from the body
Fat Soluble Vitamins
A, D, E K
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Fat Soluble Vitamins
Absorbed into the Travel lymph in blood with protein carriers Stored in the liver or with lipids in fatty tissues Can build up to toxic concentrations
FatSoluble Vitamins
Dissolve easily in fats and oils
Large intakes can result in toxicity
Deficiency less common
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WATERSOLUBLE VITAMINS
Riboflavin B2 Thiamin Thi i (B1) C Pantothenic acid Biotin Folate Vitamin (B6)
Niacin (B3)
Vitamin (B12)
WaterSoluble Vitamins
Absorbed directly into the bloodstream Travel freely--do not require a protein carrier Not stored in tissues to a significant degree Excesses are excreted in urine "expensive urine" " "
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Watersoluble Vitamins
Excess eliminated by the kidneys and cannot be stored in our bodies.
Toxicity rarely occurs
Regular intake required to avoid deficiency
Minerals
Inorganic molecules required for bodily processes
Have physiological functions, such as fluid regulation, energy production, bone structure, muscle movement, and nerve functioning.
Fluoride Trace mineral: Not technically essential buy may influence
health
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Minerals
Inorganic molecules required for bodily processes Such as fluid regulation, energy production, bone structure, muscle movement, and nerve functioning.
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What are the six nutrients?
a) Carbohydrates, water, fats, proteins, minerals, and alcohol d l h l b) Water, proteins, fats, vitamins, carbohydrates, and alcohol c) Carbohydrates, water, fats, proteins, vitamins, and minerals and minerals d) Carbohydrates, phytochemicals, water, fats, vitamins, and proteins
The six nutrients are carbohydrates, proteins, fats, water, vitamins and minerals. water vitamins and minerals Alcohol, although it contributes calories, is not a nutrient, as it provides nothing that is critical to human growth.
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Determining Nutrient Needs
PLAY
DRI Determination
Figure 1.8
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Dietary Reference Intakes (DRI) Standards
Recommended Dietary Recommended Dietary Allowances (RDA)
The average daily intake level required to meet the need of 97 98% of healthy people in a particular category. B d Based on enough scientific evidence to expect that the needs of most h i ifi id h h d f healthy people are met.
Adequate Intakes (AI)
Recommended average daily intake level for a nutrient Based on enough scientific evidence to expect that the needs of most healthy people are met. More tentative than the RDA. Used when the RDA is not yet established: calcium, vitamin D, vitamin K, fluoride
Tolerable Upper Limits (UL)
Highest average daily intake level likely to pose no risk of adverse health effects to most people Consumption of a nutrient at levels above the UL, the potential for toxic effects and health risks increases
Key 97% of population 3% of population Number of peo ople
Recommended Dietary Allowance (RDA)
Daily requirement (unit/day) If every person in this population consumed 70 units/day of this nutrient, ~97% would get enough to meet their requirements.
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Tolerable Upper Intake Levels (UL)
Dietary Reference Intakes (DRI) Standards
D Describes the portion of the ib th ti f th energy intake that should come from each macronutrient Potential for increased chronic disease risk if nutrient intake falls above this range P t ti l f i d Potential for inadequate nutrient t ti t levels if nutrient intake falls below this range
Acceptable Macronutrient Distribution Ranges ( (AMDRs) )
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Acceptable Macronutrient Distribution Ranges (AMDRs)
Provides composition of diet That provides adequate energy and nutrients Diet composition that reduces risk of chronic diseases.
Learn These!
Energy Recommendations
2000 kcal
diet:
Carbohydrate (CHO): 45% - 65% Fat: 20% - 35% Protein (PRO): 10% - 35%
EXAMPLE 50% CHO = . 50 X 2000 =1000 kcal/4 kcal = 250 gm CHO 30% FAT = .30 X 2000 = 600 kcal/9 kcal = 67 gm FAT 20 % PRO = .20 X 2000= 400 kcal/4 kcal = 100 gm PRO
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Practice on AMDR's
You recommend an 1800 calorie diet to you friend. Using the AMDR for Carbohydrates, f i d U i th AMDR f C b h d t what is the range of grams of carbohydrate your friend consume daily? (round) A. 150400 gm B 400600 gm B. 400600 gm C. 200290 gm
Nutrition Research
The scientific method The scientific method
Observation: describe the describe the phenomenon Create a hypothesis Design, collect, and analyze the data Generalize Interpret the the findings, p g data develop a theory
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Research Models
Epidemiological studies
Human experiments
Case control studies Clinical studies
Animal studies Animal studies Each method has strengths and weaknesses
Research Study Factors
Controls Sample size
Appropriate to measure a difference between between treatment groups
Placebo
Double blind
Neither subjects nor researchers know who is in the in the placebo or treatment groups
Does not receive treatment
Similar appearance and taste
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Evaluating Media Reports: Ask these questions to determine the scientific validity
Who conducted the research and who paid for it? Is the report based on reputable research studies?
Was there a control and an experimental group? Was the sample size large enough to rule out chance variation? Was a placebo effectively administered?
Who is reporting Who is reporting the information?
Was the experiment double blind?
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Evaluating Media Reports: Ask these questions to determine the scientific validity
Prior to publication p in reputable scientific journals articles undergo peer review Experiments must be repeated to confirm t dt fi or disprove the findings
Is the report based I th tb d on testimonials?
Are the claims too A th l i t good to be true?
Nutrition Advice: Who Can You Trust?
Nutrition is a new science
Potential harmful quackery
Increased interest in nutrition
Misinformation
Overwhelming amount of health claims Reliability of nutrition information
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Trustworthy Nutrition Experts
Registered Dietitian (RD)
Licensed Dietitian meets the credentialing requirements of a given state
Nutritionist has no legal definition
Professional with advanced nutrition degree
(mastersMS, MA; doctoral MA; doctoral PhD)
Physician
What factors influence your food choices?
What are your risk factors?
Obesity, physical inactivity, high blood pressure, high cholesterol, diabetes.
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May we begin the process of Learning the Science of Nutrition and Living A Healthy Diet
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