Welcome to Nutrition 150Welcome to Nutrition 150

Erica Sciara, M.S.

Nutrition education in the 1950sNutrition education in the 1950s

Photo ID: 90.2.2955, King county archives

True or False?

• Nutrition is the science that studies food and how food nourishes our body and influences health.

• True!

True or False?True or False?

• Proteins are the primary energy source for our bodies.

• False!

True or False?

• All vitamins must be consumed daily to support optimal health.

• False!

True or False?True or False?

• The Recommended Dietary Allowance is the maximum amount of nutrient that people should consume to support normal body functions.

• False!

NutritionNutrition

• The science that studies food and how food nourishes our bodies and influences our health

Why is nutrition important?Why is nutrition important?

http://www.dentistry.leeds.ac.uk/biochem/postgrad/Nutrition.htm

http://www.iceh.org.uk/files/tsno4/text/06.htm http://www.mrc-hnr.cam.ac.uk/research/bone_health/rickets.html

Niacin

Vitamin C

Vitamin AVitamin B1, thiamine

Healthful diets can reduce the riskHealthful diets can reduce the risk

• Heart disease

• Stroke

• Type 2 diabetes

• Cancer

http%3A//www.creative-nature.co.uk/catalog/index.php%3FcPath=43

ObesityObesity

Obesity in the U.S.

•CarbohydratesCarbohydrates

•Fats and oilsFats and oils

•ProteinsProteins

•VitaminsVitamins

•WaterWater

•MineralsMinerals

NutrientsNutrients

**

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Provide ENERGY!Provide ENERGY!

What Are Nutrients?What Are Nutrients?

•MacronutrientsMacronutrients: nutrients required in relatively large amounts.

– Provide energy to our bodies

– Carbohydrates, fats and oils, proteins

•MicronutrientsMicronutrients: nutrients required in smaller amounts.

– Vitamins and minerals

Energy From NutrientsEnergy From Nutrients

•We measure energy in kilocalorieskilocalories (kcalkcal).

•KilocalorieKilocalorie: amount of energy required to raise the temperature of 1g of water by 1oC.

•On food labels, “calorie” actually refers to kilocalories.

CarbohydratesCarbohydrates

•Primary source of fuel for the body, especially for the brain.

•Provide 4 kcal4 kcal per gram.

•Carbohydrates are found in grains (wheat, rice), vegetables, fruits, and legumes.

Fats and OilsFats and Oils•Fats and oils are composed of lipids, molecules that are insoluble in water.

•Provide 9 kcal9 kcal per gram.

•An important energy source during rest or low intensity exercise.

•Found in butter, margarine, vegetable oils.

ProteinsProteins

•Proteins are chains of amino acidsamino acids.

•Proteins can supply 4 kcal4 kcal of energy per gram, but are not a primary energy source.

•Proteins are an important source of nitrogen

ProteinsProteins•ProteinsProteins are important for

– Building cells and tissues– Maintaining bones– Repairing damage– Regulating metabolism

•Protein sources include meats, dairy products, seeds, nuts, and legumes.

VitaminsVitamins

• VitaminsVitamins: organic molecules that assist in regulating body processes.

• Vitamins are micronutrients that do not supply energy to our bodies.1. Fat-soluble vitamins 2. Water-soluble vitamins

VitaminsVitamins

•Fat-soluble vitaminsFat-soluble vitamins: – Vitamins A, D, E and K– Dissolve easily in fats and oils

•Fat-soluble vitamins can be stored in the body.

VitaminsVitamins

•Water-soluble vitaminsWater-soluble vitamins: – Vitamin C and the B vitamins– Remain dissolved in water

•Excess water-soluble vitamins are eliminated by the kidneys and cannot be stored in our bodies.

MineralsMinerals•MineralsMinerals: inorganic substances required for body processes.

•Minerals include sodium, calcium, iron, potassium, and magnesium.

•Minerals have many different functions such as fluid regulation, bone structure, muscle movement, and nerve functioning.

MineralsMinerals

•Our bodies require at least 100 mg per day of the major mineralsmajor minerals such as calcium, phosphorus, magnesium, sodium, potassium, and chloride.

•We require less than 100 mg per day of the trace mineralstrace minerals such as iron, zinc, copper, iodine, and fluoride.

WaterWater

•WaterWater is a critical nutrient for health and survival. is a critical nutrient for health and survival.

•Water is involved in many body processes: Water is involved in many body processes:

•fluid balancefluid balance nutrient transportnutrient transport

•nerve impulsesnerve impulses removal of wastesremoval of wastes

•muscle contractionsmuscle contractions chemical reactionschemical reactions

•many, many more…many, many more…

Determining Nutrient NeedsDetermining Nutrient Needs

•Dietary Reference Intakes (DRIs)Dietary Reference Intakes (DRIs): updated nutritional standards.

– Expand on the traditional RDA values

(or Recommended Nutrient Intake, RNI, values for Canada)

– Set standards for nutrients that do not have RDA values

Determining Nutrient NeedsDetermining Nutrient Needs

Determining Nutrient NeedsDetermining Nutrient Needs

• DRIs consist of 4 values:1. Estimated Average Requirement (EAR)

2. Recommended Dietary Allowances (RDA)

3. Adequate Intake (AI)

4. Tolerable Upper-Intake Level (UL)

Determining Nutrient NeedsDetermining Nutrient Needs

•Estimated Average RequirementEstimated Average Requirement (EAREAR)– The average daily intake level of a nutrient

that will meet the needs of half of the people in a particular category

– Used to determine the Recommended Dietary Allowance (RDA) of a nutrient

Determining Nutrient Needs: Determining Nutrient Needs: EAREAR

Determining Nutrient Needs

•Recommended Dietary AllowancesRecommended Dietary Allowances (RDARDA)– The average daily intake level required to

meet the needs of 97 – 98% of people in a particular category

Determining Nutrient Needs: Determining Nutrient Needs: RDARDA

Determining Nutrient NeedsDetermining Nutrient Needs

•Adequate IntakeAdequate Intake (AIAI)– Recommended average daily intake level for

a nutrient– Based on observations and estimates from

experiments– Used when the RDA is not yet established:

calcium, vitamin D, vitamin K, fluoride

Determining Nutrient NeedsDetermining Nutrient Needs

•Tolerable Upper Intake LevelTolerable Upper Intake Level (ULUL)– Highest average daily intake level that is not

likely to have adverse effects on the health of most people

– Consumption of a nutrient at levels above the UL is not considered safe

Determining Nutrient NeedsDetermining Nutrient Needs

•Estimated Energy RequirementEstimated Energy Requirement (EEREER)– Average dietary energy intake (kcal) to

maintain energy balance– Based on age, gender, weight, height, level of

physical activity

Determining Nutrient Needs

•Acceptable Macronutrient Distribution Acceptable Macronutrient Distribution RangesRanges (AMDRAMDR)

– Describes the portion of the energy intake that should come from each macronutrient

Determining Nutrient Needs: Determining Nutrient Needs: AMDRAMDR

Group DiscussionGroup Discussion

1.1. Why do we eat?Why do we eat?

2.2. Why do we eat Why do we eat whatwhat we eat? we eat?

For class on WednesdayFor class on Wednesday

Bring the food label from your favorite snack!Bring the food label from your favorite snack!