The Science of NutritionA Microscopic to Macroscopic Approach

Today’s Agenda

1. JEOPARDY2. Lipids3. Vitamins & Minerals4. Nutritional Density

JEOPARDYSplit into two equal teams and get out your note books.

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LipidsTypes of Lipids

Fatty AcidsFats, and Oils

Chemical Properties of Triglycerides

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Types of Lipids Lipids with fatty acids

WaxesFats and oils (trigycerides)PhospholipidsSphingolipids

Lipids without fatty acidsSteroids

What foods contain fat?

FatsFat refers to the class of nutrients known as lipids. The lipid family includes triglycerides (fats and oils), phospholipids, and sterols.

Every triglyceride contains one molecule of glycerol and three fatty acids.

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Fatty AcidsFatty acids are chains of carbon atoms with hydrogen atoms attached that have an acid group (COOH) at one end and a methyl group (CH3) at the other end.

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Fatty AcidsLong-chain carboxylic acidsInsoluble in waterTypically 12-18 carbon atoms (even

number)Some contain double bonds

corn oil contains 86% unsaturated fatty acids and 14% saturated fatty acids

Saturated v. Unsaturated Fatty Acids

Saturated fatty acids carry the maximum possible number of hydrogen atoms, while unsaturated fatty acids lack hydrogen atoms and have at least one double bond between carbons.

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Structure of Fatty AcidsSaturated = C–C bondsUnsaturated = one or more C=C

bondsCOOH

COOH

palmitoleic acid, an unsaturated fatty acid

palmitic acid, a saturated acid

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StructuresSaturated fatty acidsFit closely in regular pattern

Unsaturated fatty acidsCis double bonds

COOHCOOHCOOH

C CH H

COOHcis double bond

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Properties of SaturatedFatty Acids

Contain only single C–C bondsClosely packed Strong attractions between chainsHigh melting pointsSolids at room temperature

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Properties of UnsaturatedFatty Acids

Contain one or more double C=C bonds

Nonlinear chains do not allow molecules to pack closely

Few interactions between chainsLow melting pointsLiquids at room temperature

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Fats in Your Diet

• Try not to eat any trans fats– Increases bad (LDL) cholesterol, lowers good

(HDL) cholesterol – risk of heart disease• Keep saturated fat consumption to a

minimum• Monounsaturated and polyunsaturated

fats – between 15-30% daily caloric intake– Sources: olive oil, safflower oil, peanut oil and

corn oil• Avoid hydrogenated or partially

hydrogenated oils – added hydrogen to make it solid, preserve – check labels!

1.What foods are high in trans fat?2.What foods are high in saturated fat?3.What foods are high in unsaturated fat?4. What do you want to avoid in your diet?

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Benefits of Dietary Fats

• Fat is an essential part of your diet• Vital for your cell membranes and some cellular functions• Insulates our body• Energy supplier• Absorption and transportation

around body of fat soluble vitamins A, D, E and K

• Fat surrounds and protects organs, including our kidneys

What do you notice?

Peanut Butter Jelly

NUTRITIONAL DENSITYA Different Approach to Thinking about Nutrition

WHAT IS DESNSITY?

WHAT IS NUTRITIONAL DESNITY?

Nutritional Density = Nutrients/Calorie

How much nutritional value (mass) per one calorie (volume)

Two Types of Nutrients

Macronutrients Micronutrients

B Vitamins Bananas, seeds, green

vegetables, sweet potato, nuts

Folate Leafy greens

Vitamin E Almonds, seeds,

asparagus Vitamin C

Citrus, tomatoes, peppers, leafy greens

Vitamin D Vitamin K

Cauliflower, Broccoli, Brussle Sprouts, Greens

Vitamin Carrots,

broccoli,mango, cantaloupe

Vitamins Vitamins are organic substances bodies need to grow, metabolize, and develop normally. Deficiencies in vitamins can lead to disease and poor health.

Macrominerals Calcium Phosphorus Magnesium Sodium Potassium Sulfur Chloride

Trace Minerals Iron Zinc Copper Selenium Manganese

MineralsMinerals are the building blocks that make up muscles, tissues, and bones and are components of hormones, oxygen transport, and enzyme systems.

Flavonoids Glucosinolates

Cruciferous Vegetables

Keep Cancer in Check

Resveratrol Anti-Inflammatory

Ellagic Acid Berries

Carotenoids Provide fruits and

vegetables with red, yellow and orange color

PhytonutrientsPhytonutrients are natural chemicals found in plants. There are over 25,000 of them, and they help fight disease and keep the body working

Does anything surprise you?

A Final Note about Health

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Vitamins and Minerals

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The Nature of VitaminsVitamins are organic (carbon)

compounds needed for normal function, growth and maintenance.

Vitamins are cofactors, they don’t do anything by themselves.

They are not a source of calories.

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The Nature of Vitamins

Food processing can preserve nutrients.

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The Nature of Vitamins

Nutritional Value lost by: Light Heat Oxidation Bacteria Enzymes Insects (Nutritional value of

baby food must be assured.)

Effect of packaging on nutrient loss in milk.

Vitamin Requirements Daily Values (DV): standard nutrient intake

values developed by FDA Includes DRIs (Daily Recommended Intakes for

Individuals) and (DRVs) Daily Recommended Values (Proteins, etc.)

Disease prevention Best met through a consumption of a wide

variety of foods

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Vitamin RequirementsDietary Reference Intakes (DRI):

recommendation for individuals (more accurate, but would be impossible to label)AgeGenderPregnancyLactation

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Vitamin RequirementsDaily Reference Values (DRV):

standards established for protein and other dietary components lacking a RDA or nutrient standard

Constitute part of the Daily Values (DV) used on food labels

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The Nature of VitaminsOrganic cofactors – what is a cofactor?Physiological role – specific metabolic

functionPrevents disease – unlike “supplements”

which may promote “some thing” or have general metabolic effect

(ex. Omega 3s, fibers)

Natural = Synthetic (except Vitamin E)

Dietary Supplements $6 Billion Market

They are classified as “Nutritional Supplements” They are not foods, and not drugs.*

Supplements are “Product intended to supplement the diet and contains vitamins, minerals, botanicals, amino acids, and their extracts.”

NOT consumed as a food replacement Loosely regulated, “not evaluated by FDA”

By definition a “drug” is used to “prevent, treat or cure” disease. These terms cannot be used with supplements.

Use of some supplements is backed by scientific data.

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Fat Soluble Vitamins A – orange, carotenoids, vision, antioxidant-

used as color and antioxidant

D – we make it with sunlight, deficiency causes rickets, in milk, regulates Ca:P ratios

E – tocopherols, antioxidants, role in preventing stroke, cancer, heart disease- used as antioxidant

K – contributes to blood clotting factorA LOW FAT DIET MAY CAUSE

MALABSORBION

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Vitamin A

Lots of double bonds, good anti-oxidant

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Vitamin A

Carrotinoids Used in food industry as a colorant (orange)

Antioxidant Important for sight Dietary deficiency common in developing

countries Blindness, bone abnormalities, susceptibility

to viral infections such as measles and pneumonia

If you take a dietary supplement: teens 14-18 should not consume more than 2800mcg; 19+, 3000mcg

Cooking and storage do not reduce Vitamin A Carrotenosis

Vitamin A cont. SOURCES

Carrot juice (450%) /raw carrots (175%)

Boiled (270%)/raw (55%) spinach

Vegetable soup (115%)

Boiled Peas (20%)

Baked sweet potato with skin

Cantaloupe (110%)

Steamed broccoli

Chicken (245%)/beef (545%) liver

QUICK: CARROTS

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Vitamin D Also known as calciferol due to its role in

calcium absorption Main role is to maintain calcium and

potassium levels Part of Immune System and Nerve Signaling

It is the only fat soluble vitamin that we can make- in the presence of sunlight <1/3 of people meet dietary requirement

Can be made from cholesterol

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Vitamin D Can be stored in fat tissues (as can all

fat soluble vitamins) We get vitamin D form fortified milk and

cereal Toxicity is very dangerous

Occurs only from excess supplementation

Can lead to calcium deposits in kidneys, heart and blood vessels

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Vitamin E A family of eight naturally occurring compounds anti-oxidant Since aging is considered an “oxidation”

reaction, many “anti-oxidants” are used as dietary supplements

Protect skin, cell communication, from foods protects against prostate cancer and Alzheimer’s E in supplements = alpha-tocopherol; in food,

gamma-tocopherol Role is stroke, cancer, heart, and immune

response Americans spend $300 million per year on

vitamin E supplements E dependent on C, B3, selenium and glutathione

Vitamin E cont. Low-fat diet may cause Vitamin E deficiency

(because Vitamin E is fat-soluble!) Common in vegetable oils

SOURCES

Wheat germ oil

Dry roasted sunflower seeds

Dry roasted almonds

Safflower/sunflower oil

Dry roasted hazelnuts

Peanut butter/peanuts

Boiled spinach

QUICK: NUTS

Vitamin K Vital for blood clotting, protects bones Works as a cofactor for an enzyme that

makes two bone proteins Resilient to cooking/freezing Estimated daily value need is 80

microgramsSOURCES

Boiled kale (1/2 cup, 660%)

Boiled (1110.6%)/raw spinach

Raw parsley (153%)

Green leaf lettuce

Boiled green beans (25%)

QUICK: GREENS

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Water Soluble Vitamins

Relatively cheap to add to food

Only Vitamin C is used for its functionality

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Water Soluble Vitamins B1, thiamine B2, riboflavin B6, pyridoxamine B12

Biotin Panothenic acid Niacin Folacin Vitamin C

Water Soluble Vitamins Vitamin B1

Thiamine Involved in carbohydrate metabolism Helps body metabolize glucose, affects central

nervous system

B2- riboflavin Energy metabolism

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Water Soluble Vitamins B6 - Pyridoxamine

Neurotransmitter, co-enzyme in over 100 reactions

B12 – Development of red blood cells Lack of it makes one anemic Hard for vegans to get

Vitamin B12 cont.

SOURCES

Calf’s liver (689.8%)

Sardines (137%)

Baked/broiled snapper (66.2%)

Steamed/boiled shrimp (28.2%)

Baked/broiled salmon (54.2%)

Beef tenderloin (48.7%)

Low-fat yogurt (23%)

QUICK: FISH

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Water Soluble Vitamins Biotin –

Involved in fatty acid synthesis Deficiency causes skin disease and hair

loss

Panthothenic acid Found in many foods Essential for metabolism of

carbohydrates, protein, alcohol and fat

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Vitamin C High in citrus fruits, limes, (Limeys) Very inexpensive to add to food,

marketing tool. Antioxidant Anti-oxidant, helps immune system,

improve iron absorption Deficiency leads to bleeding gums,

hemorrhages In supplements as ascorbic acid – in

most multivitamins – check the label!

Vitamin C cont. Highly sensitive to air, water and

temperature! Fresh, raw form is bestSOURCES

Raw bell peppers (291%)

Steamed broccoli (84.8%)

Boiled cauliflower (91.5%)

Strawberries (136%)

Romaine lettuce (44.8%)

Papaya (313.1%)

Grapefruit, oranges, cantaloupe, raspberries…

QUICK: ORANGE

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Minerals Issues

AbsorptionBioavailability

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Minerals

Percent of Body weight Calcium

2% Phosphorus 1% Potassium 0.3% Sulfur 0.2% Sodium

0.1% Chloride

0.1% Magnesium 0.05% Iron 0.04%

Sodium and Chloride Small amount is essential to live;

excessive consumption increase blood pressure (stroke, heart disease…)

Ideally, limit sodium to 1500mg a day; maximum 2300mg

Most sodium intake from processed and pre-packaged foods (food preservative, enhance taste) – check labels!

Sodium & Chloride cont.

NATURALLY LOW CONTENT

Fruits

Vegetables

Fat-free or low-fat dairy

Fresh seafood and meat products

Un-salted anything

HIGH SODIUM CONTENT

Soy sauce / ketchup

Salad dressing

Chips/Pretzles

Fast food

Processed food

Potassium Reduces blood pressure, help muscle and

nerve function Kidney strictly regulates levels of

potassium Significant loses when cooked Athletes – support muscles Adults – 4700mg a day (so figure a bit

less for teens)

Potassium cont.SOURCES

Baked sweet potato (20%)

Baked potato (17%)

Non-fat yogurt (17%)

Various fish

Banana (12%)

Spinach (12-20%)

QUICK: BANANA

Iron

Oxygen transport in blood, regulate cell growth Two forms: heme (absorbed better)

and nonheme (most dietary iron) 14-18 men 11mg; women 15mg 19+ men 8mg, women 18mg Iron deficiency anemia (too few red

blood cells)

Iron cont.

HEME SOURCES

Chicken liber (70%)

Oysters (25%)

Turkey (8-10%)

Beef (20%)

Tuna (4%)

NONHEME SOURCES

Fortified cereal (100%)

Fortified oatmeal (60%)

Boiled soybeans (50%)

Kidney or lima beans (25%)

Spinach (10-20%)

Calcium

Bone health, nerve and muscle function Intake over 3000mg daily can lead to

hypercalcemia Not affected by cooking or storage Vitamin D accelerates absorption,

potassium reduces urinary excretion

Calcium cont. To improve absorption, take with meals – food

in stomach - > hydrochloric acid, which breaks down calcium carbonate

SOURCES

Milk

Boiled spinach (24.5%)

Turnip/collard/mustard greens

Low-fat yogurt (44.7%)

Mozzarella cheese, part-skim (18.3%)

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Calcium

Risk Factors- By Mayo Clinic staff

Your gender. Age. Race. Frame size. Eating disorders. Low calcium intake.Excess soda consumption (Ca:P ratio). The link between osteoporosis and caffeinated sodas isn't clear, but caffeine may interfere with calcium absorption and its diuretic effect may increase mineral loss. In addition, the phosphoric acid in soda may contribute to bone loss. Bone density can be improved at any time.

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Soda is the devil’s drink

Extra calories Poor nutrient density Interferes with

calcification Replaces more

nutritious drinks

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Minerals Sulfur

Necessary for collagen formation

Magnesium Abundant in plants

Fortification vs Enrichment Fortification - restores lost nutrients due to processing

Enrichment – adds nutritional value to meet a specific standard

 

                                

                               

Old London Restaurant Style Croutons. Seasoned Sourdough.

Enriched Bread, [Enriched Flour (Flour, Niacin, Ferrous Sulfate, Thiamin Mononitrate, Riboflavin, Folic Acid),Water,Yeast,Sugar,Salt,Partially Hydrogenated Soybean Oil ,Vinegar,Ascorbic Acid] Bean Oil with BHT added as a Dextrin