Vitamins & Minerals Flashcards
Key Vitamins (6 B vitamins - 11 Total)
Thiamin, Riboflavin, Niacin, Folate, Vitamin B6, Vitamin B12
(Water Soluble)
& vitamins A, C, D, E, K
(Fat Soluble)
Key Minerals (9 Total)
Electrolytes: sodium, potassium
Bone Health: calcium, phosphorus, magnesium
Trace Minerals: iron, zinc, iodine and fluoride
Thiamin (B1)
Sources: Whole Grains / Nuts and Seeds
Functions: Glucose and Energy Metabilism / neurotransmitter synthese and normal nerve function
Deficiency: Beriberi (‘I cannot’): weakness, apathy, irritability, confusion, nerve tingling, poor coordination, paralysis, heart changes.
Toxicity: None
- Alchohol blocks thiamin absorption
Riboflavin (B2)
Sources: Whole Grains / Dark Green Veg
Functions: Coenzyme in Energy and lipid metabolism
Deficiency: Ariboflavinosis: Inflammation of mouth and tongue / cracks at corners of mouth
Toxicity: None
Niacin (B3)
Sources: Whole Grains / Legumes
Functions: Coenzyme in Energy Metabolism / Lipid Synthesis & Breakdown
Deficiency: Pellagra: (4 Ds) dermatitis, dementia, diarrhea, death.
Toxicity: Flush (nausea, rash, tingling extremities
Vitamin B6
Sources: Whole Grains / Legumes
Functions: Coenzyme in Protein and Amino Acid Metabolism / Neurotransmitter and hemoglobin synthesis
Deficiency: Neurological Symptoms / Headache, Convulsions.
Toxicity: Numbness / Nerve Damage
Folate / Folic Acid (B9)
Sources: Leafy Greens / Legumes
Functions: Coenzyme in DNA Synthesis / Amino Acid Metabolism
Deficiency: Poor Growth / Neural Tube defects (miscarriage or spinal bifida) / Macrocytic/Megaloblastic Anemia - red blood cells don’t divide or mature properly (The most obvious sign of folate deficiency in adults) = large, immature, non-functional red blood cells
Toxicity: Masks B12 Deficiency
- Mandatory fortification of folate into enriched grains and cereals since 1998 in Canada, US
–
50% decrease in NT defects since then (Canada)
Vitamin B12
Sources: Dairy/ Meat
Functions: Coenzyme in folate and homocysteine metabolism / nerve function
Deficiency: Anemia / Nerve Damage
Toxicity: None
- B12 is required to activate folate. Thus prevents macrocytic anemia
Vitamin C
Sources: Citrus Fruit / Broccoli
Functions: Coenzyme in Collagen (connective tissue) Synthesis / Antioxidant
Deficiency: Poor Wound Healing / Decreased Immune Function
Toxicity: GI Distress / Diarrhea
Vitamin A
Sources: Retinoids: liver, fish / Carotenoids: Carrots / Leafy Greens
Functions: Vision Health (cornea) / Cell Differentiation (can turn genes on/off)
Deficiency: Xerophthalmia: Night blindness (early stages) dry cornea, eye infections, can lead to blindness
Toxicity: Headaches, Vomiting, Liver Damage
Vitamin D
Sources: Egg Yolk / Synthesis from Sunlight
Functions: Absorption of calcium and phosphorus / Bone Maintenance
Deficiency: Rickets (Bones don’t calcify properly - bend/misshapen bones, soft bones) / Osteomalacia (weak bones - decreased bone mass, risk of fractures)
Toxicity: Growth Retardation
Vitamin E
Sources: Veg Oils / Leafy Greens
Functions: Antioxidant ? Protects Cell Membrane
Deficiency: Hemolytic Anemia (Broken Red Blood Cells - common in premature infants) / Nerve Damage
Toxicity: Inhibition of Vitamin K Activity
Vitamin K
Sources: Veg Oils / Leafy Greens
Functions: Synthesis of blood-clotting proteins & proteins in bones
Deficiency: Hemorrhage
Toxicity: Anemia / Brain Damage
- Vit K is needed for the production of several clotting factors, that allow the blood to clump, so wounds can heal
Sodium (electrolyte)
Sources: Table Salt / Processed Food
Functions: Muscle Contractions / + extracellular ion / Fluid Balance
Deficiency: Muscle Cramps
Toxicity: High Blood Pressure
Potassium (electrolyte)
Sources: Fresh Fruit & Veg / Legumes
Functions: Muscle Contractions / + intracellular ion / Fluid Balance
Deficiency: Muscle Cramps
Toxicity: Abnormal Heartbeat
Calcium
Sources: Dairy / Leafy Greens
Functions: Bone and Teeth Structure / Heart & Muscle Contractions
Deficiency: Increased Risk of Osteoporosis
Toxicity: Kidney Stones
Phosphorus
Sources: Dairy / Baked Goods
Functions: Bone and Teeth Structure / membranes
Deficiency: Weakness / Bone Loss
Toxicity: Calcium (deficient) Resorption from Bone
Magnesium
Sources: Greens / Nuts & Seeds
Functions: Bone Structure / Nerve & Muscle Function
Deficiency: Weakness / Muscle Pain
Toxicity: Nausea / Vomiting
Iron
Sources: Leafy Greens / Legumes
Functions: Needed for immune function / Oxygen Transport [Part of Hemoglobin (which delivers oxygen to cells), Myoglobin (which holds oxygen in muscle) and proteins needed for ATP production]
Deficiency: Anemia / Weakness
Toxicity: liver failure
Zinc
Sources: Meat / Seafood
Functions: Regulates Protein Synthesis / Functions in growth, development, healing.
Deficiency: Rashes
/ Poor growth and skin development
Toxicity: Decreased Copper Absorption
/ Depressed Immune Function
Iodine
Sources: Iodized Salt / Dairy
Functions: Synthesis of Thyroid hormones
Deficiency: Slower Metabolic Rate
Toxicity: Enlarged Thyroid
Fluoride
Sources: Fluoridated Water / Toothpaste
Functions: Strengthens Tooth Enamel / Reduces acid production by bacteria in the mouth.
Deficiency: Risk of dental caries
Toxicity: Kidney Damage / Bone Abnormalities
How much of vitamins can we absorb?
Approx 40-90% of vitamins in food absorbed
Vitamins are organic therefore susceptible to destruction by:
HEAT, UV LIGHT or OXIDATION
Prevent losses of Vitamins by:
Refrigeration of fruits and vegetables
Storing cut vegetables, fruits, and juice in airtight containers to reduce oxidation
Wash fruits and vegetables before cutting
Steam vegetables in small amounts of water, avoid over cooking
The B Vitamins Function Primarily as:
Coenzymes
• Bind to enzymes to promote their activity
• Carry electrons, atoms, chemical groups
- An active Vitamin combined with a chemical group to form the functional coenzyme
- The Functional Coenzyme combines with the incomplete enzyme to form the active enzyme
- The Active Enzyme binds to one or more molecules and accelerates the chemical reaction to form one or more new molecules
- The new molecules are released, and the enzyme and coenzyme (vitamin) can be reused or separated.
Vitamin B12/ Vitamin B6 Needed to:
Prevent Rise in Homocysteine Levels (HCL)
High levels of homocysteine in the blood is a risk factor for cardiovascular disease.
But consuming these B vitamins beyond recommended levels does not provide additional cardiovascular benefits
Antioxidants
Protect against oxidative damage by free radicals - FR’s steal electrons, damage structure and function
- Oxidative damage associated with cancer, diabetes, heart disease, possibly Alzheimer’s and Parkinson’s
Vitamin D and Calcium Regulation
Calcium is an essential nutrient needed in many critical body processes
- Nerve conduction, heart/muscle contraction etc.
When levels drop, parathyroid hormone (PTH) is released, which activates vit D at kidney
Activated vitamin D, through its role in gene expression,:
- Promotes Ca2+absorption at SI
- Reduces Ca2+excretion at the kidneys
- Mobilizes Ca2+from bone
Vitamin D Activation
Whether from diet, sun-related synthesis, it is inactive until modified by liver and kidneys
Please note! You do not absorb vitamin D from the sun! When light energy from the sun hits the skin, it triggers the reaction that helps synthesize an inactive form of vitamin D from precursors.
Dietary Supplements are Recommended For:
Dieters (<1600 kcal/day)
Vegans/ those that eliminate dairy (B12, vit D, Ca2+)
Infants and children (fluoride, vit D, iron)
Young Women/ pregnant women (400 μg of folate)
Older adults (B12, vit D)
Dark-skinned indvs (vit D)
Indvs with restricted diets (depends)
People taking certain medications (depends)
Smokers (Vit C, maybe E)
Alcohol users (B vitamins)
Minerals (Key Points)
Inorganic elements found on the periodic table, throughout nature
> 20 essential minerals found in plants/animals
Present naturally in foods or added from soil, food processing
Major minerals: need >100 mg/d
Trace minerals: need <100 mg/d
Mineral Bioavailability
Depends on the source (ex. soil quality of where plants are grown), what else is eaten at the same time, the preparation and the individual
In general, minerals are easier to absorb from animal products vs. plant products
–
Plants may contains oxalates, phytates, tannins and fibre that can bind minerals in GI tract and reduce absorption (next slide)
Oxalates, Tannins and Phytates:
Compounds that Interfere with Mineral Absorption
Oxalates: - Calcium & Iron (Spinach, Rhubarb, Beet Greens, Chocolate)
Tannins: - Iron (Tea, Red Wine, Some Grains)
Phytates: - calcium, zonc, iron, magnesium (Whole Grains, Bran, Soy) * Broken down by yeast; bioavailability higher in foods with yeast.
Some Minerals can Function as Cofactors, Activating Enzymes:
B vitamins can function as coenzymes, while minerals can function as cofactors. They both facilitate enzymatic activity by helping activate enzymes
- The Mineral cofactor combines with the incomplete enzyme
- The active enzyme binds to the molecules involved in the chemical reaction (compound A&B) and accelerates their transformation into final products (Product X&Y).
- The final product is released while the enzyme remains unchanged.
The Electrolytes
Sodium, Potassium, Chloride
Charged ions (+ve/-ve) that are responsible for the electrical activity of the body
Sodium = main extracellular ion, potassium = main intracellular one
Also regulate fluid balance
Deficiency typically associated with excessive sweating, diarrhea, vomiting
Electrolytes in Disease
Hypertension: ‘The Silent Killer’
aka High blood pressure
Most common health problem related to minerals
Can lead to atherosclerosis, heart attack, stroke, kidney disease, death
Affects 1/5 adult Canadians
15% of people with hypertension don’t know they have it!
Risk factors: genetic factors, age, (abdominal) obesity, physical inactivity, alcohol, stress, diet (next slide)
DASH diet
dietary approaches to stop hypertension
Diets ↑ in salt (sodiumchloride) = ↑ risk
Diets ↑in K, Ca, Mg = ↓ risk
- associated with a ↓ blood pressure
–
High in whole grains, fiber, F/V, low in fat, lean meats, limited fats and sweets
–
These results are exacerbated by low sodium intake
Major Minerals in Bone Health:
Calcium, Phosphorus, Magnesium and Sulfur
Bone Overview
Bone is composed of a protein matrix (i.e. Collagen) hardened by mineral deposits
–
Calcium and phosphorus form hydroxyapatite crystals, which mineralize bones and teeth
•
Bone is always remodelling: breaking down and building up
–
This process involves three cell types
•
Osteoclasts-bone breaking cells
•
Osteoblasts-bone building cells (immature bone cells)
–
Become osteocytes (mature bone cells) when incorporated into bone
Bone Remodelling
When blood calcium is low, osteoclasts break down bone to release calcium
When blood calcium is high or adequate, the mineralization of bone is favoured
Until ≈ age 30, you have a limited time to build up bone mass! After that it declines for everyone
–
Esp. Women, esp. after menopause
•
due to drop in estrogen
•
Weight-bearing activity, calcium, vitamin D important to prevent
Osteoporosis:
reduced bone mass
Calcium Regulation
Drop in blood calcium levels= ↑parathyroid hormone release, which stimulates
–
Bone reabsorption: ↑osteoclast activity to release Ca2+ from bone
–
Reduced Ca2+ loss in urine at the kidneys
–
↑activity of Vitamin D
–
Increases Ca2+ absorption at kidneys
•
Increase in blood calcium levels = ↑ calcitonin release
–
Primarily works on bone to inhibit Ca2+release into blood
Trace Minerals
iron, zinc, iodine and fluoride
Iron Absorption and Bioavailability
Bioavailability depends on type of iron in food
•
Heme iron-part of hemo/myoglobin; in animal sources
–
More easily absorbed (2x that of non-heme iron)
•
Non-heme iron-found in plant sources
–
Harder to absorb
–
Absorption improved when eaten with sources of heme iron, vitamin C
•
Absorption decreased by fiber, phytates, tannins, oxalates
•
Vegetarians (especially female ones) are at increased risk for iron deficiency
Iron Deficiency
Iron deficiency anemia (most common nutritional deficiency in the world) =late stage iron deficiency
–
Results in pale, small rbc’s; fatigue, weakness, headache
Pica
Minerals are so critical to the function of the body, that deficiencies of certain minerals my trigger Pica, an appetite for non-nutritive substances such as dirt, clay or sand that may contain minerals within
Copper deficiency
can also lead to iron-deficiency anemia because a copper-containing protein is required for iron absorption
Selenium
Part of glutathione peroxidase;an antioxidant
Deficiency can lead to Keshan’s Disease (a heart disease), in areas where soil is low in selenium
