Download What is a Diet

What is a Diet?
•The foods a person normally eats and drinks
•Does NOT necessarily mean a weight loss regimen or other special eating plan
Malnutrition
•Any condition resulting from a deficient or excessive nutrient intake, or an imbalance
of nutrient intake
•Overnutrition or undernutrition can occur
•Overnutrition and undernutrition can coexist in the same person
“Overfed, Undernourished”
(from 2004 Dietary Guidelines Committee)
•80% of children, 86% of men, & 93% of women don’t get enough vitamin E
•2/3 of adults are low on magnesium
•40% of men and over 50% of women don’t get enough calcium
Primary Nutritional Deficiency
•Inadequate intake alone
•In US, a primary deficiency of just one nutrient is rare
•Possible exception: iron
Secondary Nutrient Deficiency is Due to Other Factors
•Increased needs (e.g., pregnancy, growth)
•Increased losses
•Reduced absorption
•Negative interactions with other nutrients, dietary constituents, or drugs
Recommended Dietary Allowances (RDA)
•First edition was published in 1943
•Nutrient standards, not guidelines
•Updated as more nutrients were discovered and more data were available on optimum
intakes
•Emphasis has changed from preventing deficiency to assuring good health
The Dietary Reference Intakes
•Encompass and surpass the RDA’s
•Have come out in piecemeal fashion over last 7 years
–First came bone-related vitamins & minerals
–B vitamins
–Vitamins C & E, selenium, carotenoids
–Vitamins A & K, rest of minerals
–Macronutrients, fiber, & cholesterol
–Finally, water and electrolytes (Na, K)
Alphabet Soup
•DRI = Dietary Reference Intakes; umbrella term that encompasses all of terms below
•EAR = Estimated Average Requirement
•RDA = Recommended Dietary Allowances
•AI = Adequate Intake
•UL = Tolerable Upper Limit
Estimated Average Requirement
(EAR)
•Nutrient intake estimated to meet needs of 50% of persons in a specific age and gender
group; defined by a specific biomarker of adequacy
Recommended Dietary Allowance (RDA)
•Amount of nutrient that satisfies requirement for 95+% of population; 2 standard
deviations above EAR
Adequate Intake (AI)
•Set for nutrients for which an EAR cannot be set due to lack of definitive information;
e.g., vitamin D, fluoride, calcium, biotin
Tolerable Upper Limit (UL)
•Point at which higher intake of a specific nutrient could be harmful
Uses of DRI’s
•Planning and assessing diets for healthy people
•Nutrition policy--guidelines for school lunches and breakfasts; food packages for the
Special Supplemental Food Program for Women, Infants, and Children (WIC)
Just because you consume less than the RDA for a nutrient doesn’t mean you’re deficient
•Remember the RDA has a large safety factor built in
Nutrition Guidelines
•Often a source of confusion to consumers, and a source of exasperation to professionals
Some Common Themes of All Guidelines
•Moderation
–Too much of a good thing may not be
•Variety
–Mix things up
•Balance
–Not too much, not too little of each food group
•Adequacy
•Kcal control
•Nutrient density (see p. 41)
The Food Guide Pyramid
•Introduced by US Department of Agriculture in 1992
•A visual representation of the Dietary Guidelines, with serving numbers attached
What’s a serving size?
•Probably a lot less than you think!
Serving sizes
–Breads, Cereals, & Pasta--1 slice bread; 1/2 small bagel; 1/2 cup cooked rice, cereal, or
pasta (Not 1/2 cup dried rice or pasta, cooked); 1 small biscuit, muffin, or roll
•Vegetables--1/2 cup cooked or raw vegetables; 1 cup leafy raw vegetables
•Fruit--1 medium banana, apple, or orange; 1/2 grapefruit, 1/2 cup berries, 1/2 cup
cooked or canned fruit; 1/4 cup dried fruit; 3/4 cup juice
•Meats, etc.--2-3 ounces cooked lean meat; 1 egg; 1/2 cup cooked legumes*; 2
tablespoons peanut butter
•Dairy--1 cup milk or yogurt; 2 ounces processed cheese; 1 1/2 ounces “real” cheese
Pyramid Problems
•No allowances for differences between foods within a group
–1 hot dog = 1 skinless chicken breast
–1 serving broccoli = 1 serving cucumber
–1 slice “fluffy bread” = 1 slice whole grain bread
A Not-So-Fun Fact
•According to Gladys Block of UC Berkeley, sweets, desserts, soft drinks, fruit-flavored
drinks, alcoholic beverages, and salty snacks make up 30% of all kcal in the US diet
Dietary Guidelines for Americans
•Joint effort by US Dept of Agriculture and Food and Drug Administration
•Begun in 1980, updated every 5 years
•Latest update in August 2004
•NOT THE VERSION IN TEXTBOOK
So what are these Guidelines?
•Consume a variety of foods within and among the basic food groups while staying
within energy needs.
•Control calorie intake to manage body weight.
•Be physically active every day.
Increase daily intake of fruits and vegetables, whole grains, and nonfat or low-fat milk
and milk products.
•Choose fats wisely for good health.
•Choose carbohydrates wisely for good health.
• Choose and prepare foods with little salt.
•If you drink alcoholic beverages, do so in moderation.
• Keep food safe to eat.
“Just tell me how I’m supposed to eat already!!!”
•Be conscious of what you’re eating, based on the Food Guide Pyramid
•Read labels (stay tuned)
•Opt for foods that are less processed
–More fiber
–Less added salt and sugar
–More nutrient dense
•Choose lower-fat milk and dairy products
•Try eating legumes and tofu as meat alternatives
•Cook with less fat
•Go with leaner meats
–trim fat
–skin chicken