Ch. 1 What is Nutrition? Flashcards
Factors that affect food choices (7)
1) Taste and enjoyment
2) Culture and environment
3) Social life and trends
4) Nutrition knowledge
5) Advertising
6) Time, convenience, and cost
7) Habits and emotions
Food preference (4)
- begins in infancy (introduce new foods at 6 months)
- may be influenced by genes (gut and brain play role)
- changes as we age
- repeated exposure
Living environment
availability and accessibilty
Food environment (3)
- size and shape of plates and glassware
- packaging of foods
- lighting
Group size
individuals eat more food when eating with others
40% more
Activity
food intake increases when eating during activity (movie)
Popular trends
frozen vegetables and organic foods
Nutriton knowledge
- perception of food as unhealthy or healthy
- current state of health affects food choices
Advertising
influences food choices, especially for children and adolescents
- mostly for unhealthy foods
- personalized nutrition
Time, convenience, and cost
- busy schedules = prepared foods
- fast food is cheaper
Nutrition
the science that studies how nutrients and compounds in foods nourish the body and affect body functions and overall health
Food in the body (5 steps)
- digested (starts in mouth)
- absorbed (stomach)
- transported (intestines, moving within organs)
- metabolized (occurs in every cell)
- used or stored in the body
- chewing is form of digestion
- excretion: urine, sweat
Nutrients
compounds in foods that serve as building blocks for body components and sustain body processes
- help replace dead cells
Six categories of nutrients
- carbohydrates
- fats (lipids)
- protein
- vitamins
- minerals
- water
(alcohol provides energy but is NOT a nutrient)
Nonnutrient compounds in food
- nondigestible fiber
- chemicals
- phytochemicals
- zoochemicals
Water
most abundant nutrient found in foods and in the body
- 60% of body
Plant foods
made up of 10% carbs, fats, proteins, vitamins and minerals (the rest is water: 90%)
Animal foods
made up of 30% protein, lipids, vitamins and minerals (the rest is water: 70%)
Organic nutrients (4)
contain carbon when energy breaks down, carbon is one of end products - carbohydrates - proteins - lipids - vitamins
Inorganic nutrients (2)
do NOT contain carbon
- minerals
- water
Nitrogen
- found in protein and some vitamins
- excreted through urine
Essential nutrients
- required
- consumed from food
- cannot be made in body in sufficient amounts
Nonessential nutrients
- can be made in sufficient quantities in the body
- conditionally essential nutrients: nonessential nutrients become essential
ex. vitamin D
Amino acids
- essential or nonessential nutrients
- used to synthesize, grow, and maintain tissue
Energy
- capacity to do work
- body derives energy from nutrients in foods that store energy in chemical bonds (energy is ATP, released when bonds are broken)
Energy-yielding nutrients
- carbohydrates
- lipids (fats)
- proteins
- *all fats are lipids, but not all lipids are fats (ex. cholesterol is a lipid but not a fat)
Nonnutrient source of energy
alcohol
Kilocalorie (kcal)
energy required to raise temperature of 1 kg water 1 degree Celsius
- measurement of energy in foods
- 1 kcal = 1,000 calories
Kilocalories per gram
Carbohydrates = 4 kcal/g
Protein = 4 kcal/g
Fat (lipids) = 9 kcal/g
Alcohol = 7 kcal/g
Energy in body
- energy is trapped within bonds that keep molecules together (bonds break, energy is released)
- unused energy is stored as fat
- using more energy results in fat breakdown
Individual nutrient roles
- supply energy
- regulate metabolism (ATP)
- provide structure (proteins, vitamins, and minerals)
Macronutrients
- nutrients the body needs in large amounts
- carbohydrats, fats (lipids), protein, and water
Micronutrients
- essential nutrients the body needs in smaller amounts
- vitamins and minerals
Carbs composition
carbon, hydrogen oxygen
Carbs function
supply glucose, the primary energy source for many body cells including red blood cells and brain cells (nervous system)
Carbs food sources
plants: breads, cereals, legumes, nuts, fruits, and vegetables
animals: dairy products (lactose)
Lipids composition
carbon, hydrogen, and oxygen
- more concentration and contain less oxygen and water than carbs
Lipids function
- provide energy to cells
- structural component to cell membranes
Three categories of lipids
insoluble in water
- triglycerides (rest and sleep)
- sterols
- phospholipids (similar to triglycerides)
Lipids food sources
margarine, butter, oils, and animal products
Triglycerides
- stored in adipose tissue beneath skin
- insulate the body and cushions organs
Proteins composition
Caron, oxygen, hydrogen and nitrogen
Protein function (6)
- contribute the basic building blocks (amino acids)
- build and maintain body tissues
- primary source of tissues is muscle, bones, and skin
- participate as neurotransmitters
- play a role in immune system
- act as enzymes (catalysts)
Protein examples in body
hemoglobin: red blood cells
insulin: regulates blood sugar levels
Protein food sources
animals: meat, poultry, fish, and dairy
plants: legumes, soy, nuts and seeds
Vitamins and minerals composition
vitamins: carbon, hydrogen and oxygen
minerals: just mineral
Vitamins and minerals function
- do not provide energy
- metabolism regulation (metabolize carbs, fats, and proteins)
Deficiencies in vitamins and minerals can cause
- fatigue (lack of energy)
- stunted growth
- weak bones
- organ damage
Vitamins function
- coenzymes: help enzymes catalyze reactions in body
- activate enzymes that participate in bone/muscle building, energy production, fighting infections, and maintaining healthy nerves/vision
Water-soluble vitamins
- excreted (not stored in body)
- need to be consumed daily
- eight B-complex vitamins and vitamin C
Fat-soluble vitamins
- stored in body (liver and the organs)
- Vitamins A, D, E, and K
Minerals function
- assist in body processes
- essential to structure of hard and soft tissues like bone and red blood cells
Major (macro) minerals
- fluid balance, energy production, muscle contraction
- need at least 100 mg/day
- found in amounts of at least 5 grams in the body
Trace (micro) minerals
- transport oxygen and carbon dioxide, cell growth and development, metabolic rate, antioxidants
- need less than 100 mg/day
- found in amounts of less than 5 grams in the body
Water functions (5)
- essential during metabolism
- digestion and absorption (delivers nutrients and oxygen to cells and excretes waste products through urine)
- maintains body temperature
- lubricant for joints, eyes, mouth, and intestinal tract
- cushions vital organs
Nutrient deficiencies
can lead to chronic deficiencies, excesses, and imbalances which affect long-term health
Well-balanced diet
- whole grains
- fruits and vegetables
- lean meats
- low-fat dairy
- also provides phytochemical, zoochemicals, and fiber
Fiber
cannot be converted to blood sugar
- not a nutrient
- not enough fiber leads to constipation
Functional foods
may provide additional health benefits
Phytochemicals
nonnutritive plant chemicals
- disease fighting characteristics
Zoochemicals
nonnutritive animal compounds
- help fight chronic diseases
- strong antioxidant benefits
- ex. omega-3 fatty acids from fish improve heart health and reduce inflammation
Leading health related causes of death
heart disease, cancer, stroke, diabetes
Chronic diseases
stem from our genetic makeup, environment and our diet
Nutrition genomics
studies relationship between gene expression, nutrition, and health
Nutrigenics
genes respond to nutrients we eat
Nutrigenomics
nutrients influence genetic expression
Malnourished
wrong amount of essential nutrients
Undernourished
lack of sufficient essential nutrients
Overnourished
excess energy or nutrient
Anthropometric
appearance (body size or body composition)
- height, weight, bmi, waist-to-hip, waist circumference
- determines growth, obesity, weight changes, risk of developing diseases
Biochemicals
nutrient levels in body fluids
- blood, urine, and feces
- determine protein, mineral and vitamin status and disease
Clinical
body inspected for potential deficiencies
- hair, fingernails, skin, lips, mouth, muscles, joints, overall appearance
- determines sign of deficiencies and excesses of nutrients
Dietary intake
diet
- diet history, diet record, FFQ, 24-hour recall
- unusual nutrient intake, deficiencies or excesses
Food frequency questionnaire (FFQ)
identifies patterns of intake over time
Food record
most accurate
- diary of foods and beverages eaten, how much, and timing
24-hour recall
client recalls food and drinks eaten in previous day
National Health and Nutrition Examination Survey (NHANES)
evaluate nutritional statu of Americans of all ages (large population)
- used to develop current dietary recommendations
Framingham Health Study
heart health risk factors
- two generations, 10,000 people
- establish recommendations for cardiovascular disease
- connection between blood cholesterol levels and heart disease was revealed
Excess intake
- added sugar
- sodium
- saturated fat
Too little intake
- fiber
- vitamin D
- Potassium and calcium
- women tend to be low in iron
Obesity leads to higher rates of:
- type 2 diabetes
- heart disease
- cancer
- stroke
Overweight bmi
greater than 24.9
Obese bmi
greater than 29.9
Credible nutrition research
advice based on a consensus of multiple research findings
Scientific method
process used by scientists to gather and test information for the sake of research findings
- observe and ask question
- formulate hypothesis
- conduct experiment
- hypothesis supported or not supported
- if not supported, revise
Peer-reviewed journals
where findings are published
- hypothesis supported
- publish findings
- develop theory
- establish consensus
Laboratory experiment
done in lab setting
Observational research
explores factors in two or more groups to determine relationship between a disease or health outcome
Epidemiological research
- type of observational esearch
- examines health and disease in population of people
Experimental research
- involves experimental group (given treatment)
- control group (given placebo)
- double-blind placebo-controlled: gold standard (researcher and participant are blinded)
Medical nutrition therapy
nutrition counseling and dietary changes based on individual medical and health needs to treat a patient’s medical condition (administered by RDN)
Public health nutritionists
undergraduate in nutrition
Licensed dietitian nutritionist (LDN)
expert in field of nutrition (RDN )
Nutritionist
no credible training in nutrition
Quackery
promotion or selling of health products, profit is motive
