What Are Vitamins?

• Tasteless organic compounds

• Required in small amounts

• Functions:

Regulate Metabolism

Help convert the 3 Organic Energy Yielding Nutrients into ATP

Promote Growth and Reproduction

Deficiencies can result in serious illnesses.

Vitamins Discovered about 100 Years Ago

1747 - British Navy Dr. James Lind gave sailor limes to combat scurvy – Vitamin C deficiency.(*Vit C not discovered until 1930’s)

1897 - Dutchman Christiaan Eijkman observed chickens & people eating white rice developed Beriberi, causing heart problems & paralysis. When chickens fed unprocessed brown rice (outer Bran intact), no disease developed: Brown rice cured his patients too.

Connected Food to Curing Disease.

Note: Outer rice bran contains vitamin B1, (Thiamin).

History of Vitamins

1912 - E.V. McCollum, discovered first fat soluble vitamin, Vitamin A; found rats fed butter were healthier than those fed lard (more Vitamin A in butter).

1912 - Dr. Casmir Funk coined term ‘vitamins’ as vital factors in diet (from vital and amine). Found these unidentified substances in food could prevent diseases of scurvy, beriberi and pellagra (from deficiency of niacin, vitamin B3).

1940’s - Water soluble B and C vitamins were identified.

1968 - Linus Pauling, created the term Orthomolecular Nutrition, "pertaining to the right molecule". Connecting optimum nutrition to better health.

1970's-1980's – Further studies by Pauling et al. suggested very large doses of intravenous vitamin C could help increase survival time and improve the quality of life of terminal cancer patients.

Naming Vitamins

• Each new vitamin given a temporary name when discovered.

• Names of vitamins follow alphabet, starting with A; A, B, C, D, E, and K… where we currently are

• Vitamins F, G, and H were dropped.

• Nomenclature changed when vitamin B was found to have several functions.• Subscripts added for each new isolated role.

The Criteria for Designating Vitamins:

1. Cannot be synthesized in ample amounts in body

2. Chronic deficiency cause physical symptoms.

3. Symptoms disappear once vitamin level restored.

4. Deficiency can cause permanent damage.

13 compounds meet the above criteria!

Classifying Vitamins:

Vitamins are classified based on solubility.

• Nine (9) Water-Soluble:• B vitamin complex• Vitamin C

• Four (4) Fat-Soluble:• Vitamin A• Vitamin D• Vitamin E• Vitamin K

Solubility Influences a Vitamin’s…

• Digestion• Absorption• Transportation• Storage• Excretion

Compare Water Soluble and Fat Soluble Vitamins

Vitamins Are Organic

Vitamins:

• All contain C, H and O.

• Can also contain some N and S.

• Each have a unique Chemical structure.

• Are each a singular unit.

• Are absorbed intact.

• Perform numerous essential functions, some with more than one role in metabolism.

The many roles of Vitamins in maintaining Health

Pro-Vitamins Converted to Active Vitamins

• Provitamins - substances in foods that are not directly usable by the body.

• Converted to an active form once absorbed

• Example: beta-carotene vitamin A

• Preformed Vitamins• Vitamins in foods in their active form.• Do not need to be converted.

Vitamins Differ in Absorption and Storage

• All absorption takes place in the small intestine.• Fat-soluble and water-soluble vitamins differ in:

• Absorption• Bioavailability

Bioavailability - proportion of the nutrient that is digested, absorbed and metabolized through normal pathways.

Absorption – passage of the nutrient after digested into the blood and lymph and body cells.

Vitamins Differ in Bioavailability

• Bioavailability of Vitamins Varies:• Amount in specific food• Preparation (raw, fermented, cooked)• Efficiency of Digestion and Absorption of food• Individual Nutritional Status• Natural or Synthetic in Form!

• Fat-soluble vitamins are generally less bioavailable than water-soluble vitamins.

• Vitamins from plant foods are generally less bioavailable than those in animal foods.

Fat-Soluble Vitamins Stored after Absorbed

• Absorption • Attached to proteins in foods, released in the stomach• Absorbed in the duodenum• Packaged in chylomicrons lymph bloodstream• Lack of fat can lead to deficiency.

→ →

• Storage• The liver is the main storage site for vitamin A; to a

lesser extent for vitamins K and E.• Vitamin D is mainly stored in the fat and muscle tissue.• Can build up in the body to the point of toxicity

Water-Soluble Not Stored after Absorption

• Absorption• Absorbed with water directly into bloodstream• Most absorbed in the duodenum and jejunum

• Excretion• Not stored in the body• Excess intake excreted through the urine

Consume adequate amounts dailyDietary excesses may be harmful.

Digesting and Absorbing Vitamins

What Are Antioxidants?

Compounds that Neutralize Free Radicals.

What Are Free Radicals?

Unstable organic molecules with unpaired valance electron

Free Radicals damage the cells of your bodyFactors that free radical production:• Exposure to Ingested Toxins

• Exposure to Environmental Pollutants• Excessive UV-A Exposure

Oxidative Stress

Oxidative stress - when free radicals accumulate faster than body can metabolize them.

Damages DNA and body proteins, alters cell structure.

Excess free radicals = chronic diseases! Including

Heart DiseaseCancerAging

DiabetesParkinson's DiseaseAlzheimer's Disease

Antioxidants Neutralize Free RadicalsInclude: Vitamin E, C, Carotenoids, Selenium, Flavonoids.

Phytochemical Rich Foods

Phytochemicals are naturally occurring plant compounds that stimulate immune system, interact with hormones to prevent cancers.

• Carotenoids• Flavonoids

• Natural sources of phytochemicals in food always have more health benefits than those from supplements.

e.g. Flavonoids Resveratrol

(indoles)

Best Sources of Vitamins

• Whole Foods and Nutrient DenseFruits, vegetables, whole grains and dairy.All are rich in vitamins, phytochemicals, antioxidants, and fiber

• Dietary Guidelines for Americans Rec:Eat a wide variety of foods from each food group, with ample amounts of vitamin-rich fruits, vegetables, whole grains, and dairy foods.

Most people should not need supplements.

Vitamins Can Be Destroyed by:Cooking or Storage

• Exposure to Oxygen• Water-Soluble Vitamins• Vitamins A, E, and K

• Exposure to Ultraviolet (UV) Light• Riboflavin (B2)• Beta-carotene (A) and vitamin C

• Water• Most Water-Soluble vitamins – leach into H2O

• Changes in pH• Thiamin and Vitamin C

• Heat• Most water-soluble, esply vitamin C

Vitamins Can Altered by Prepartation

• Vegetables and fruits begin to lose their vitamins almost immediately after being harvested

• Some preparation and storage accelerate vitamin loss.• Fat-soluble vitamins more stable.

Vitamin Toxicity

• Vitamin toxicity (hypervitaminosis) is Very Rare• Ingesting excess vitamins => tissue saturation• Can damage cells. • From supplements (megadoses); cannot occur

from eating whole foods.

WHY are some Foods Fortified with Vitamins?• Fortified foods: Addition of nutrients by manufacturers,

often by FDA regulation:• For Low Quality food – to Replace nutrients that

were taken out of the original food source.• Prevent or correct dietary deficiencies• Ensure adequate intake – for those who know

absolutely nothing about good food : )

• Enrichment ~ Fortification.• Fortification can contribute to health risks.

• Lead to vitamin excess• Displace nutrient-rich foods (i.e. you forget to eat

real, nutritious healthy life giving foods!)

Vitamin A• Vitamin A is a Family of fat-soluble Retinoids:

Retinol, Retinal, Retinoic Aacid

Retinol Retinal Retinoic Acid

• Animal foods• Stored in Body• Function:

Reproduction

• Found in plants• Retinal = Vision• Retinoic = Regulates growth

Carotenoids Are pigmented molecules in plants that give intense orange, yellow and even red colors to a variety of fruits and vegetables.

The carotenes that act as antioxidants are:1)alpha carotene2)beta carotene 3)lycopene

Beta-Carotene A very important Carotenoid in Human Nutrition; a pigment deep orange/yellow (e.g. carrots and pumpkin).

The human body has 2 functions for carotenes:

1. It turns it into Vitamin A 40% of carotenes

2. It turns it into an antioxidant. 60% of carotenes

LycopeneBright Red carotene phytochemical.

Tomatoes are a perfect example.

Watermelon, papayas, guavapink grapefruit.

Also in asparagus, brown beans and parsley

Not in:Cherries, Strawberries or Red Bell Peppers.

Unlike beta carotene, it cannot convert into vitamin A.

Vitamin A Absorption and Transport

• Vit A absorbed by active transport with bile & micelles.

• Beta-carotene absorbed by passive diffusionReduced with high fiber intake : (Improved in cooked foods : )

Packaged into chylomicrons and enter lymph.

Retinoic acid is attached to albumin.

Stored in the liver!

Body Functions of Vitamin A

• Participates in:• Vision• Gene Transcription and Translation (Pro-Syn)• Cell Differentiation• Reproduction • Bone health• A healthy immune system

+ help fights cancer - Carotenoids are antioxidants.

Vitamin A and Your EyesightAssists your Eyes in 3 major ways:

1) Prevents Night Blindness

2) Prevents Cataracts (like Vitamin C)

3) Preserve Eyesight throughout life

Retinal and Its Role in Vision1) Night BlindnessRods are photoreceptors for black and white vision in the retinaThe protein opsin and retinal need to combine in orderFor rods to function properly.

Cataracts2) CataractsThe lens of the eye becomes cloudy, impairs vision.

From the Latin word catracta, meaning “waterfall”, as your vision isas if you are looking through one.

Vitamins C and E lutein and zeaxanthin lower cataract risk.

Macular Degeneration

3) Macular Degeneration Involves the destruction of the macula lutea in center of retina where most of the cones (for color vision) reside.

Protect with Vitamins C, E, beta-carotene, zinc and copper

Daily Needs—Vitamin A

• Males: 900 μg and Females: 700 μg retinol• UL: 3,000 μg• Beta-carotene: 3 to 6 mg daily

• Excessive preformed A can be toxic. • However, cannot be toxic levels from eating foods rich in

vitamins, only from supplements.

• >15,000 μg can cause symptoms of toxicity. • Hypervitaminosis A may lead to liver damage and death!

Carotenoids in foods cannot be toxic, excess carotenoids can cause carotenodermia

Vitamin A Deficiency

• Chronic Deficiency => Night Blindness.• Prolonged deficiency => Xerophthalmia – pathologic

dryness of conjunctiva and cornea of eye.

• Deficiency can lead to keratinization of epidermis

• Epithelial cells cannot secrete mucus and unable to function properly, promoting infection.

Vitamin DThe “Sunshine Vitamin"

Need two things!1) Ultraviolet (UV) rays. 2) Form of Cholesterol in the skin.

All your vitamin D needs can be met by exposure to sunlight : )

Considered a prohormone - Found in two forms:

1) Cholecalciferol (vitamin D3) = in our skin and in animal foods

2) Ergocalciferol (vitamin D2) = in plants & dietary supplements

The Chemical Structure of Vitamin D

Epidermis of Skin

Dermis of Skin

7-dehydrocholesterol

UV Light+

Cholecalciferol (Vit D3)

Your cells only make Vitamin D if UV B stimulation is adequate (~20 min/day)

“Calcidiol” 25-Hydroxycholecalciferol

(25-Hydroxy Vit D3)Allow your healthy Liver to process Vit D3 into Calcidiol.

“Calcitriol”1,25-Hydroxycholecalciferol

(1,25-Hydroxy Vit D3)

ACTIVE FORM

Allow your healthy Kidneys to process Calcidiol into the most active form,

Calcitriol.

UV B Light

UV B Light

The story of Vitamin D

Great Food Sources of Vitamin D

Worlds Healthiest Foods for Vitamin D

FoodServing

Size CalAmount

(IU)DRI/DV

(%)NutrientDensity

Salmon 4 oz 157.6 511.43 128 14.6

Sardines 3.20 oz 188.7 175.09 44 4.2

Milk 4 oz 74.4 62.22 16 3.8

Tuna 4 oz 147.4 92.99 23 2.8

Eggs 1 each 77.5 43.50 11 2.5

Mushrooms ½ cup 40.6 20.30 5 2.2

Metabolic Functions of Vitamin D

• Bone Growth• Calcitriol Ca2+ and PO4

3- absorption.• Balances Osteoblasts and Osteoclasts actions.

• Powerful stimulator of Immune System• Reduces Autoimmune Disorders• Prevent Diabetes Mellitus Type 1 by 50% in adults• Type 2 Diabetes assoc with low blood Vit D levels.• Role in Blood Pressure regulation• Significant role in Mood: Lack of D => Depression

Daily Needs - Vitamin D

Cells called Melanocytes in epidermis of skin make the dark pigment Melanin – makes you tan after sun exposure – then it protects you like natural suncreen!

The darker your skin, the more sun exposure you require to have adequate vitamin D production.

Sunlight intensity during winter in some locations is not sufficient to make enough vitamin D.

Daily Needs Vitamin DAdults: 15 to 20 μg (600 to 800 IU)/day

Upper limit (UL) ~ 100 μg (4,000 IU)Children: 15 μg per day

UL: 50 μg (2,000 IU)

• High intake - loss of appetite, nausea, vomiting, and constipation.

• Hypervitaminosis D can lead to hypercalcemia and calcium deposits in vital organs.

• Too-high levels are very rarely caused by food intake or overexposure to the sun.

Vitamin D Deficiency

• Rickets in children• Inadequately mineralization causing weak bones. • milk consumption, fear of skin cancer from sun

exposure, and air pollution

• Osteomalacia adult equivalent of rickets

• Osteoporosis: Significant loss in Bone Density leads to increased fractures!

• Muscle and bone weakness and pain

Vitamin EAlpha-tocopherol most active form in body.

Synthetic form in supplements only ½ as active.

Vitamin E

Vitamin E Absorption and Transport

• Absorbed with bile and micelles

• Into chylomicrons ⟶ lymph ⟶ blood ⟶ liver

• 90% vitamin E stored in Adipose tissue.

Metabolic Functions of Vitamin E

• Acts as an Anticoagulant, inhibiting formation of harmful clots inside bloodstream.

Metabolic Functions of Vitamin E

Powerful AntioxidantProtects cell membranes; prevents oxidation of LDL cholesterol

• Adults: 15 mg of alph-tocopherol.• UL: 1,000 mg/day

Daily Needs—Vitamin E

Vitamin E Toxicity and DeficiencyNo risk of too much vitamin E from food sources!

Too much synthetic form may risk of a hemorrhage.

Deficiency Symptoms in Adults Mild Anemia, Fragile RBCs Neurological Damage Disorders related to Reproduction and Infertility Age spots, Cataracts Muscle, liver, bone marrow brain abnormalities Decrease in Sex Drive

Significantly more free radical damage to cell membranes

Vitamin K

• 3 forms of vitamin K• Menaquinone from intestinal bacteria. K1• Phylloquinone is found in green plants. K2 • Menadione is the synthetic form

Vitamin K Absorption and Transport

• Most absorbed in Jejunum.• We only get ~10% vitamin K from our bacteria. : (

• Into chylomicrons and to liver.

• When a diet is deficient in vitamin K storage forms are transported by VLDL, LDL, and HDL.

• Stored mostly in liver

Metabolic Functions of Vitamin K1

Vitamin K1 Promotes Blood ClottingInvolved in synthesizing 4 blood-clotting factors!

1) Green Leafy Vegetables (Kale) ½ c: 444 mcg (over 100% DV)

2) Natto (Fermented soy) 2 oz: 500 mcg (over 100% DV)

3) Spring Onions (Scallions) ½ c: 103 mcg (over 100% DV)

4) Brussels Sprouts ½ c: 78 mcg (98% DV)

5) Cabbage ½ cup: 82 mcg (over 100% DV)

6) Broccoli ½ c: 46 mcg (58% DV)

7) Dairy (Fermented) ½ c: 10 mcg (10% DV)

8) Prunes ½ c: 52 mcg (65% DV)

9) Cucumbers 1 med 49 mcg (61% DV)

10) Dried basil 1 Tbsp: 36 mcg (45% DV)

Natural Foods Rich in Vitamin K1 and K2

Natural Foods Rich in Vitamin

K2

Metabolic Functions of Vitamin K2

• Activates Osteocalcin protein

• Activates Matrix Gla Protein (MGP)

Vitamin K2 Activate 2 crucial Proteins for Ca2+

Daily Needs—Vitamin K• Adults: Men: 120 μg/day, Women: 90 μg/day

• No known adverse Toxicity• If on anticoagulant medications should keep vitamin K

intake consistent! Changes in intake can increase or decrease drug effectiveness.

• Deficiency• Heart Disease and Vitamin K deficiency go hand in hand!• Deficiency severe enough to affect blood clotting is

extremely rare.

Are Vitamin Supplements Necessary for Good Health? • Supplements:

• *Supplements can't be removed unless they have been shown to be unsafe or cause harm.

• How to choose a supplement

• Read the label carefully.

Vitamins and Good Health

• Will be helpful if your diet is Lacking. Also for:

• Pregnant and lactating women

• Older individuals who need vitamin B12

• Those who lack dietary vitamin D or sun exposure

• Vegetarians and Vegans

• Those with food allergies or lactose intolerance

• Individuals who abuse alcohol