What is nutrition?
"the science of food, the nutrients and substances therein, their action, interaction, and balance in relation to health and disease, and the process by which the organism ingests, digests, absorbs, transports, utilizes, and excretes food substances."
Why should you care about your diet?
Poor diet associated with 4 of 10 leading causes of death (type 2 diabetes, heart disease, stroke, breast/colon cancer)
Other than a nutritious diet, only 2 common lifestyle habits have a stronger influence on long-term health. What are they?
Nutrition involves the study of...
biochemistry, biology, physiology, behavioral sciences, chemistry
What role does diet play in chronic or long-term health?
Heart disease, cancers (breast and colon), stroke, & diabetes
What role does diet play in short-term health?
Fiber - relieves constipation; caffeine -gives energy, athletic performance, affects sleep; alcohol -motor skills
6 classes of nutrients (kcal/gm in parentheses)
carbohydrate (4), protein (4), fat (9), water (0), vitamins (0), minerals (0)
4 Research designs
epidemiologic studies (know this definition), case studies, intervention studies (RCT), laboratory studies
All of the following are correct concerning
the Daily Reference Intake (DRI) values
except: A. the committee that determines the
values is composed of scientists.
B. the values are minimum
recommendations for virtually all healthy
C. the values are updated periodically in
light of new knowledge.
D. the values reflect daily intakes to be
achieved, on average, over time.
B. the values are minimum recommendations for virtually all healthy people
To look up the appropriate DRI values for
someone, you would need to know all of the
following about them except:
a. whether they were pregnant or lactating.
b. their sex.
c. their level of physical activity.
d. their age.
c. Their level of physical activity
According to the Acceptable Macronutrient
Distribution Ranges (AMDR), what percentage
of total calories should come from
a. 20 to 35 percent.
b. 45 to 65 percent.
c. It depends on what type of carbohydrate.
d. 10 to 35 percent.
b. 45 to 65 percent
AMDR stands for...
Acceptable Macronutrient Distribution Ranges; 45-65% from carbs, 20-35% from fat, 10-35% from protein
Daily Values (DVs)
5% DV or less is considered low; 20% DV or more is considered high; DVs for some nutrients represent the uppermost limit (total fat, saturated fat, cholesterol, sodium)
function of proteins
used for structural components (bones, skin, teeth, etc.); NOT usually used for energy
main function of water
maintenance of fluid balance, elimination of waste, and transport of substances
red flags of unreliable nutrition info
promises of quick/easy remedies; claims that sound too good to be true; scare tactics; attacks on conventional scientists and medical practitioners; statements abt the superiority of natural dietary supplements; testimonials or anecdotes; info promoting product's benefits while overlooking its risks; vague/scientific sounding terms; sensationalism; recommendations based on a single study; etc.
websites w/ reliable nutrition & health info
eatright.org; nih.gov (Nat'l Institutes of Health); fda.gov; cdc.gov; acsh.org (American Council on Science and Health); quackwatch.org; ncahf.org (Nat'l Council Against Health Fraud)
epidemiology is the study of:
disease rates among different popul. groups, factors associated w/ disease occurrence, and how diseases are spread
limitations of epidemiologic studies
results could be coincidence; cannot establish causation; difficulty in determining which variable is responsible for the condition
studies of populations in which observation is accompanied by experimental manipulation of some population members; control and experimental groups; RCT-gold standard
studies of individuals; in clinical settings; researchers observes tx and apparent effects
studies that are performed under tightly controlled conditions and are designed to pinpoint causes and effects; use animals or cells
quality nutrition research is....
peer reviewed, published in a respected nutrition-related journal, and reported at a nutrition or medical meeting
before acceptance for publication, research articles undergo critical analysis by peer experts in the field who were not part of the research team
encompass a variety of terms that describe values for nutrient recommendations. There are the basis for planning diets for large groups - military, school lunches, etc.
Who established the DRIs?
Food and Nutrition Board, Institute of Medicine, Nat'l Academy of Sciences; Panels of experts; chosen by the Nat'l Academy; independently selected. funded by DHHS, USDA, Health Canada, private industry. Serially published: 1997 & counting. (www.iom.edu)
Purpose of DRIs
standards for planning large scale diets (to aid in nutritional adequacy, to promote health/reduce risk of chronic disease); to provide a measure for evaluating inadequacy and/or excess; to assess population intakes and plan meals for large groups
What are characteristics of the DRIs?
separate values (men and women); age groups; pregnancy and lactation; apply to healthy individuals; refer to average daily intakes; may vary substantially from day to day w/o ill effect in most cases
assigned when no RDA can be determined. Assumes a population's avg daily nutrient intakes are adequate
The DRI committee has set values for:
Viatmins, minerals, carbs, fiber, lipids, protein, water, and energy
DRI committee's Acceptable Macronutrient Distribution Ranges (AMDR)
45-65% from carbohydrate, 20-35% from fat, 10-35% from protein
Calorie needs are a little different however. Values are NOT set at 98% like RDA/AI. Why not?
Bc there is an obesity epidemic in this country and there is no need to recommend more calories than needed as this is detrimental. Calories set at 50% (like EAR) so this is what an avg person would need.
Dietary Guidelines for Americans 2010
Nutrition-related lifestyle recommendations intended for people over 2 years of age; released every 5 years by law; 2010 guidelines released January 31, 2011 by USDA and HHS. Designed to promote adequate nutrition and good health; reduce risk of CVD, obesity, alcoholism, and other nutrition-related chronic conditions; form the basis for federal nutrition policy - including food assistance programs
How many grams of fat should be consumed on an 1800 calorie diet at 25% fat?
1800 x.25=450 kcal
450 kcal/9kcal/gm=50 grams
similarities and differences between mypyramid, Harvard's healthy eating pyramid and Dr. Weil's anti-inflammatory pyramid
nutrient dense vs energy dense
nutrient dense foods have a lot of nutrition per bite whereas energy dense foods have a lot of calories per bite but aren't necessarily nutritious
Dietary Guidelines for Americans 2010
Recommendations: increase intake of whole grains, reduced intake of sugar-sweetened beverages, focus on the total number of calories consumed, and monitor food intake; reduce sodium intake; limit saturated fats to 10% of total cals (substitute mono and poly unsat fats); limit cholesterol to less than 300 mg/day; keep trans fat intake as low as possible; increase intake of fruits and vegetables; eat a variety of vegetables, especially dark-green and red and orange vegetables and beans and peas; consume at least half of all grains as whole grains (not refined); increase amount and variety of seafood; increase in-take of fat-free or low-fat milk and milk products (yogurt, milk, cheese, or fortified soy beverages); choose foods that provide more potassium, dietary fiber, calcium and vitamin D; use oils to replace solid fats where possible
dietary moderation (3 steps)
obtain enuf nutrients from food + avoiding excessive amounts of nutrients + balancing calorie intake with expenditure
amount of a nutrient within the range of safe intake that enables the body to function optimally
state of health that occurs when the body is improperly nourish; may be from inadequate OR excessive amounts of nutrients