Exam 2 Flashcards
How many known vitamins are there?
14
What are the fat-soluble vitamins?
- Vitamin A
- Vitamin D
- Vitamin E
- Vitamin K
What are the water-soluble vitamins?
• B-complex vitamins □ Thiamine (vitamin B1) □ Riboflavin (vitamin B2) □ Niacin (Vitamin B3) □ Vitamin B6 (pyridoxine) □ Folate □ Vitamin B12 □ Biotin □ Pantothenic acid • Vitamin C • Choline (vitamin-like compound)
What are the B Vitamins?
- thiamine
- riboflavin
- niacin
- vitamin B6
- folate
- vitamin B12
- biotin
- pantothenic acid
What are vitamins?
- Organic compounds (Contain both carbon-carbon and carbon-hydrogen bonds)
- Micronutrients
- Essential nutrients (must be consumed in the diet)
- Individual units
- Are not a source of energy (calories)
Why are vitamins needed?
to extract energy from macronutrients
How are vitamins classified?
according to their solubility
What does solubility determine?
how vitamins are absorbed and transported in body
What does a vitamin’s solubility affect?
where vitamins are stored and risk for toxicity
What are some common characteristics of fat-soluble vitamins?
- Insoluble in water
- Dissolve in lipids
- Small amounts needed
- Absorption in small intestine
- Leave small intestine in chylomicrons
- Stored in tissue
- Potential for toxicity
- Often present in fatty portion of foods
What is Vitamins A’s primary function?
vision and cell differentiation, function as hormones
What is Vitamin D’s primary function?
bone growth and maintenance, cell development, immunity
What is Vitamin E’s primary function?
antioxidant
What is Vitamin K’s primary function?
blood clotting and bone formation
How is vitamin D produced?
in the skin from cholesterol adn exposure to UV light
What is Vitamin D’s nickname?
sunshine vitamin
Why is it essential to consume vitamin D?
insufficient sun exposure
Can Vitmain D be consumed through the diet?
yes
How can vitamin D be activated in the body?
Must be activated in the kidneys and liver to function in the body
What are the richest sources of vitamin D?
fatty fish and fish liver oil
Does Vitamin D occur naturally in many foods?
no, besides fish
What is the most common source of Vitamin D in the US Diet?
fortified foods
What does Vitamin D primarily function as?
a hormone
What are the functions of Vitamin D in the body?
- Acts as a hormone
- Helps bone growth and maintenance
- Regulates calcium metabolism
* Blood levels- Absorption
- Excretion
- Regulates the synthesis of certain proteins
- Possibly regulates cardiovascular function
- Ongoing research of other roles in the body
What groups are at risk of Vitamin D deficiency?
- avoid vitamin-D fortified foods
- people with dark skin
- inadequate sun exposure
- exclusively breast-fed infants
- elderly
Is Vitamin D a nutrient of concern?
yes
Why are the elderly at risk of vitamin D deficiency?
○ Reduced ability to synthesize vitamin D
○ Reduced sun exposure
○ Potential diminished intake
What can extremely low levels of vitamin D cause overtime?
rickets, osteomalacia
What group of fat-soluble compounds does Vitamin A encompass?
retinoid compounds and carotenoids
What are the types of retinoid compounds?
Retinal, Retinol, Retinoin acid
What is the only retinoid present in significant amounts in our diet?
retinol
What is retinol called and why?
Called preformed Vitamin A as already in active form in foods
What are carotenoids?
Provitamin as only has vitamin activity after conversion to active form in the body
What is the primary carotenoid in our diet?
beta-carotene
What does the bioavailability of Vitamin A differ upon?
food source
What are sources of provitamin A carotenoids?
Yellow-, orange-, and red-pigmented fruits and vegetables
Where are preformed vitmain A founds?
animal foods and fortified foods
What is different about preformed vitamin A?
more readily absorbed
What unit is the RDA given in for retinol?
Retinol Activity Equivalents (RAE)
Why is the RDA for retinol in RAE?
- Conversion of beta-carotene to retinol is never complete
* Absorption of carotenoids from food is poor
How can you improve the bioavailability of retinoids?
slicing, chopping, cooking, juicing and cooking
Where is most Vitamin A consumed in the US diet?
preformed sources (animal foods)
What are the critical biochemical and physiological functions of vitamin A in the body?
vision
functions as hormone
How does beta-carotene play an important role?
potent antioxidant properties
What are plant forms of Vitamin A?
carotenoids and beta-carotene
What do carotenoids and beta-carotene function as?
antioxidants
What do antioxidants help with?
Help protect cells from oxidative damage caused by reactive molecules called free radicals
What do high levels of free radicals cause?
cellular damage
What is the leading cause of blindness in children worldwide?
vitamin A deficiency
What does hypovitaminosis A cause?
- Night blindness
- Permanent blindness
- Impaired immunity
What can consuming too much vitamin A cause?
hypervitaminosis A
Who especially needs to be cautious of excess vitamin A and why?
pregnant women - can cause birth defects
Does excess beta-carotene from plant sources cause toxicity?
no
What are the best sources of vitamin E?
nuts and some oils
What is one good source of vitamin E?
almonds
What does vitamin E function as?
an antioxidant within cellular membranes
What is vitamin E less toxic than?
vitamin A and D
Where is a significant amount of our Vitamin K produced by?
intestinal bacteria
What are dietary sources of Vitamin K?
leafy greens, some fruits, some cheese, some oils
What does vitamin K play a key role in?
blood clotting
What does vitamin K reduce the risk of?
hemorrhage in newborns
What is a standard procedure at birth?
to provide vitamin K injection or oral medication
What are characteristics of water-soluble vitamins?
- Dissolve in water
- Small amounts needed
- All except choline function as coenzymes
- Most circulate freely in blood
- Can be destroyed or removed during food storage or preparation
- Not stored in large amounts, low risk toxicity
Why do water-soluble vitamins have a low risk of toxicity
- excess generally excreted in urine
- excess generally from supplements not food sources
How do B vitamins differ?
each has a distinct structure and function
What do B vitamins function as?
coenzymes in chemical relactions
What do B vitamins help to accomplish?
chemical reactions that release energy from carbohydrates, proteins and fats
What is a coenzyme?
a compound that binds to a protein (enzyme) and is required for its function
What is Thiamin’s function?
coenzyme form in energy metabolism
What does a deficiency in thiamin cause?
beriberi
What does beriberi cause?
Causes muscle wasting, fatigue, and mental disturbances
What does niacin deficiency cause?
pellagra
what are symptoms of pellagra?
- Fatigue
- Dermatitis
- Diarrhea
- Mental deterioration
- Death
What is niacin’s function?
energy metabolism
How do people get excess intake of B vitamins?
through supplements
What products are fortified or enriched with B vitamins?
grain products
What is fortification?
addition of nutrients
What is enrichment?
replace nutrients extracted from grains when they are refined
What can B vitamins lower?
lower cholesterol
How does riboflavin function as?
energy metabolism
What are good sources of riboflavin?
milk and dairy foods
What destroys riboflavin?
UV Light
Where is riboflavin deficiency typically seen?
chronic alcohol abuse
Does riboflavin deficinecy typically occur on its own or with other deficiencies?
with other b vitamin deficiencies
What is B6’s function in the body?
coenzyme
What is Pantothenic acid’s role?
energy metabolsim
What is the RDA for folate?
400 mcg
What is the other form of folate?
folic acid
What are the functions of folate?
- Acts as a coenzyme in metabolism of certain amino acids
- Helps in DNA and RNA synthesis
- Helps with normal cell division and development
Where is folic acid found?
supplements and fortified foods
What does folate deficiency cause?
megaloblasic anemia
What does adequate intake of folate or folic acid prior to conception prevent?
2/3 of neural tube defects
What helps women reach the RDA for folate?
enriched grain products
What is B12 bound to?
proteins
What does B12 require for absorption?
acid and intrinsic factor in stomach
What does B12 act as?
a coenzyme
Where is B12 found naturally?
foods of animal origin
What does B12 deficiency cause?
megaloblasic anemia
What is B12 metabolism closely linked with?
folate
What are symptoms of megaloblasic anemia?
○ Increased fatigue during physical activity
○ Tingling or lack of sensation in legs and arms
○ Cognitive impairment and problems with motor control
What groups are at risk of B12 deficiency?
- Vegans (consume no animal foods)
- Gastric bypass patients
- Individuals with pernicious anemia (lack intrinsic factor)
- Elderly
What does risk of B12 deficiency increase with?
age
What are age related risk factors for B12 deficiency?
- Diminished intake
- Impaired absorption
- Reduced gastric acid and intrinsic factor
What is choline?
a vitamin-like compound classified as an essential nutrient
Can the body synthesize choline?
yes
What are the functions of choline?
Intertwined with function of folate and vitamin B12
What is Vitamin C also known as?
ascorbic acid
What are the functions of Vitamin C?
- Acts as coenzyme in biological reactions
- Aids in hormone production
- Involved in collagen synthesis
- Enhances iron absorption
- Antioxidant
Where is vitamin c found?
many fruits and some vegetables
Why do you need to be careful with vitamin C?
readily destroyed by storage and cooking
What does Vitamin C deficiency result in?
scurvy
What does Vitamin C intake above the UL cause?
GI issues
What is the RDA for Vitamin C for Men?
90 mg
What is the RDA for Vitamin C for women?
75 mg
What is the UL for Vitamin C?
2000 mg
What does overconsumption of vitamin C cause?
diarrhea, bloating
What defined “Dietary Supplement”?
Dietary Supplement Health and Education Act (DSHEA) of 1994
What is a dietary supplement?
Food or substance that supplements the diet and contains one or more dietary ingredients or their constituents
What are considered dietary supplements?
Vitamins, minerals, herbs, other botanicals, amino acids, or enzymes
How are dietary supplements intended to be taken?
by mouth
What are the forms of dietary supplements?
pill, capsule, tablet, liquid, powder, and bar
Who should take supplements?
Those who cannot meet their nutritional requirements because of disease, increased need, or restricted diets
What are common groups who would benefit from dietary supplements?
- Infants and children (vitamin D)
- Women who may become pregnant (folic acid)
- Pregnant women (folic acid, iron, multivitamin)
- Vegans (vitamin B12 and D, calcium, iron, zinc)
- Those who do not consume dairy products (vitamin D and calcium)
What supplement would infants and children take?
vitamin D
What supplement would women who may become pregnant take?
folic acid
What supplement would pregnant women take?
folic acid, iron, multivitamin
What supplement would vegans take?
vitamin B12, vitamin D, iron, zinc, calcium
What supplement would people who dont consume dairy products take?
vitamin D and calcium
What supplement would adults older than 50 take?
vitamin B12 and D
What supplement would those would dark skin take?
vitamin D
What supplement would individuals on restricted diets take?
multivitamin
What supplement would smokers, alcohol-depndent individuals, adn those taking some medications take?
multivitamins
What supplement would women wiht heavy menstrual periods take?
iron
What supplement would individuals who frequently donate blood, as well as those with stomach adn intestinal conditions, take?
iron
What are nutrients of concern (9)?
Vitamin A Vitamin C Thiamine Niacin Vitamin D Calcium Iron Vitamin B12 Folate
Do dietary supplements have to be approved by teh FDA for effectiveness or safety?
no
Who regulates dietary supplements?
DSHEA
What is the manufacturer of supplements responsible for?
ensuring that the product is safe, unadulterated, produced with good manufacturing practices, and properly and truthfully marked with a label
What are the laws concerning dietary ingredients in supplements?
have to be federally regulated and GRAS (generally recognized as safe)
How can a product’s use be restricte or removed from market?
FDA has to prove the product is not safe
Do GRAS substances need FDA approval before being marketed?
no
What makes something Generally Recognized as Safe?
- Dietary supplement ingredients (and food additives) that were present in the food supply prior to October 15, 1994 are presumed safe and thus “grandfathered”
- Or have published studies on safe consumption
- However, many dietary ingredients legally present in supplements have not been reliably demonstrated to be safe
Are dietary supplements regulared more like food or drugs?
food
What does the FDA’s 1994 Dietary Supplement and Education Act require of supplemets?
- Supplements are safe
- Unadulterated
- Be properly labeled
- Be produced with food manufacturing practices
- Promoted with label information that is truthful
What expanded some of the FDAs authority with supplement manufacturers?
Food Safety Modernization Act (FSMA)
Does the FDA require manufacturers to list certian details about their products on the label?
yes
What are health claims?
Describe a relationship between a dietary supplement ingredient and reduced risk of a disease or condition
How can a health claim be made?
Must be FDA approved based on Significant Scientific Agreement (SSA)
What are qualified health claims?
FDA approved, emerging evidence
When can a health claim be made?
when there is significant scientific agreement that evidence supports a link between a supplement ingredient and disease
When can a qualified health claim be made?
when there is emerging evidence that supports a link between a supplement ingredient and disease
What must be done before a manufacturer can make a label claim?
approved by FDA
Structure/Function claims?
• describe the effect on the structure or function of the body and do not make reference to a disease
• mandatory disclaimer
Example: “Promotes healthy joints” or “Supports the immune system”
What does the FDA not monitor regarding supplements?
quality assurance, potency, purity, or efficacy
What does FDA track regarding supplements?
reports of illness, injury or reactions
What are supplement manufacturers required to report to the FDA?
serious harmful effects
What supplements pose higher risks?
High Potency supplements
Why do High Potency supplements pose higher risks to individuals?
- Significantly in excess of the Daily Values for one or more nutrients/ingredients
- Sometimes in excess of the UL (Tolerable Upper Intake Level) above which there are documented adverse effects
- No current law prohibits supplement potency, except for potassium
- Taking high levels for a prolonged time can be toxic
- Can result in nutrient-nutrient imbalances/interactions
- high doses of some nutrients may reduce absorption and utilization of other nutrients
What are some tips for taking supplements?
- Read the label carefully
- Look for products with quality assurance seal
- Take note of the expiration date
- Consider formulas for men, women, and age groups
- Do not overdo it
What is good about botanical or herbal supplements?
Less potent form of many drugs, but can still have drug-like effects
What are functional foods?
contain nutrients or other constituents that enhance their contribution to health and disease prevention
What’s another name for functional foods?
nutraceuticals
What are types of functional foods?
whole foods or enhanced processed foods
Is there a legal definition for functional foods?
no
What may functional nutrient-dense foods contain?
disease fighting phytochemicals
Do functional foods have health benefis beyond the vitamins and minerals they traditionally contain?
yes
How many essential minerals are there?
16
How are minerals categorized?
by the amount required in the diet
What are the major minerals?
- Sodium
- Potassium
- Chloride
- Calcium
- Magnesium
- Phosphorous
- Sulfur
How much is required of major minerals?
> 100 mg/day
How much is required of trace minerals?
<100 mg/day
What are the trace minerals?
- Iron
- Zinc
- Copper
- Iodine
- Selenium
- Molybdenum
- Fluoride
- Manganese
- Chromium
How much of our body weight do minerals compose?
4%
What is most of our mineral body weight?
calcium
What are minerals?
ions
What do ions allow minerals to do?
participate in chemical reactions and bond with other molecules
What are the regulatory and structural functions of minerals?
- Part of hormones and enzymes
- Transmit nerve impulses
- Maintain fluid balance
- Support immune system
- Act with enzymes as cofactors to facilitate chemical reactions
- Work in partnership with other minerals
What affects the bioavailability of minerals?
- nutritional status
- competition with other minerals
- presense of binders in foods
What are some binders in foods?
phytates, oxylates, polyphenols, other minerals
is tap water a source of some essential nutrients?
yes
Where are minerals founds?
across all food groups (plants, whole unprocessed foods, animal foods)
What do plant’s mineral content reflect?
mineral content of soil
What are the structural roles of minerals?
bone formation and maintenance
What minerals play an importnat role in bone?
calcium, magnesium, phosphorus
What is the most abundant mineral in the body?
calcium
Where is 99% of calcium found?
bone and teeth
What is calcium’s purpose in bone and teeth?
structural component, reservoir of calcium
What are food sources rich in calcium?
dairiy foods, leafy greens, some legumes
What is the AI for calcium for adults 19-50?
1000 mg/day
What decreases the risk of osteoprosis?
Achieving a higher peak bone density
What may cause higher levels than recommended of calcium?
Calcium supplements combined with fortified dietary sources
What is a cofactor?
a nonprotein compound that facilitates enzyme function
What is the function of magnesium?
a cofactor
What is magnesium important for?
bone health
Where is phosphorus found?
in every cell of the body
What is phosphorus a component of?
bone and cartilage
What are the electrolytes?
sodium, potassium, and chloride
What do electrolytes do?
- Maintain fluid balance
- Transmit nerve impulses
- Muscle contraction
- Transport nutrients
What are electrolytes?
Electrically charged minerals (ions) dissolved in body fluids
What is the primary electrolyte in extracellular fluid?
sodium
What are the functions of sodium?
- Regulating fluid balance
- Regulating blood pressure
What helps electrolytes balance fluid outside cells and with fluid inside cells?
kidneys
Where do we get most of our sodium from?
processed, packaged, and restaurant foods
What is the AI for sodium?
1500 mg/day
What is the UL for sodium?
2300 mg/day
What is the average intake of sodium?
3400 mg/day
How much sodium is in 1 teaspoon of table salt?
2400 mg sodium
What does overconsumption of sodium increase risk of?
hypertension
Does blood pressure rise with sodium intake?
yes
What is hypertension?
blood pressure >= 130/80 mmHg
What is hypertension a major risk factor of?
cardiovascular diease and stroke
What is the DASH eating plan effective for?
helping lower blood pressure and reduce the risk of heart disease
What does DASH stand for?
Dietary Approaches to Stop Hypertension
Who recommends the DASH diet?
American Heart Association and American College of Cardiology
What is the primary electrolyte within cells?
protassium
What are potassium’s functions?
- Regulating fluid balance
- Acting as a cofactor for certain enzymes
- Helping nutrient transport
- Helping maintain electrical activity of the heart
What may potassium help with?
counter effects of excess sodium on blood pressure
Where is potassium mostly found?
minimally processed foods, particularly fruits and vegetables
What are mild form of potassium deficiency?
• Increase risk of hypertension, stroke, and heart attacks
How much potassium do most Americans consume?
half of recommended
What does severe depletion of potassium cause?
hypokalemia
What does potassium toxicity result from?
supplement misuse
What are symptoms of potassium toxicity?
- Low heart rate
* Abnormal heart rhythm
What is Chloride?
an electrolyte found in extracellular fluids
What is chloride commonly found in?
table salt
What is chloride involved in?
fluid balance
What are the function of water?
- Regulates body temperature
- Transports nutrients and oxygen
- Lubricates joints
- Present in mucus and saliva
- Cushions tissues
- Acts as a solvent
- Participates in chemical reactions
- Removes waste
How much of our bodies are made up of water?
60-70%
Do males or females have more total body water?
males
How much of our muscle is water?
75%
How much of our adipose tissue is water?
15%
How does water move in and out of cells?
osmosis
How much of water is intracellular?
2/3
How much of water is extracellular?
1/3
What does the direction of osmosis depend on?
the concentration of solutes
How does one remain in water balance?
fluid input must equal its output
What is the best way to determine adequate daily hydration need?
thirst
How much does food contribute to total water intake?
20%
Under what circumstances are our fluid needs increased?
- Illness and fever
- High-protein diets – excrete excess nitrogen
- High fiber diets
- Alcohol consumption
- Working in hot, humid conditions
- Athletes
Why do you need more water when sick?
to replenish losses and prevent dehydration
Why do you need more water when on a high fiber diet?
to offset losses in stool
Why do athletes need more fluids?
Strenuous activity and hot humid weather increase needs up to 50%
What indicates hydration status in athletes?
Pre- and post-exercise body weight indication of hydration status
What are symptoms of dehydration?
- Nausea
- Dizziness
- Elevated temperature
- Concentrated urine
What is excess water consumption without electrolytes called?
hyponatermia
What are symptoms of Hyponatremia?
- Confusion
- Nausea
- Vomiting
- Bloating
- Swelling around the brain
What are the trace minerals?
iron, iodine, zinc, copper, selenium, molybdenum, fluoride, manganese, and chromium
What are general properties of trace minerals?
- Less than 100 mg required daily
- Circulate freely in the blood
- Found in both plant and animal foods
- Many serve as co-factors for enzymes
- Require very little digestion
- Absorbed mostly in the small intestine
Where are trace minerals found?
animal and plant foods, differe bioavailability
What influences the bioavailability of trace minerals?
- Form of the food
- Nutrition status
- Age
- Pregnancy
Do trace minerals have a narrow or wide safe range of intake?
narrow
What influences iodine content in food?
depends upon content of the environment it comes from
What are sources of iodine?
- Seafood
- Milk
- Processed grains
What is iodine an essential component of?
thyriod hormone
What is iodine required for?
normal function of thyroid gland
What does iodine deficiency cause?
ability of thyroid gland to produce thyroid hormones
What are symptoms of hypothyroidism?
- Slow metabolic rate
* Goiter
What can mild forms of iodine deficinecy cause in pregnancy women?
can affect neurological development
What is the difference between heme and non-heme iron?
non-heme iron is more influenced by other dietary components that inhibit absorption
What is iron a crucial component of?
hundreds of enzymes and other proteins in the body
What is iron required for?
chemical processes
• Energy metabolism
• Immune response
• DNA synthesis
What is iron important for?
reproduction, growth, healing
What is the most abundant trace mineral in our bodies?
iron
What is iron present in?
heme and non heme
What are the types of heme iron?
hemoglobin, myoglobin
What is heme iron critical component of?
hemoglobin
What is the iron-containing protein in muscle?
myoglobin
What do hemoglobin and myoglobin do?
Oxygen is carried by hemoglobin in blood and supplied by myoglobin in muscle
what are food sources of heme iron?
red meats, poultry, fish
What are food sources of non-heme iron?
lentils, beans, dried fruits, fortified grain products
What increases the absorption of iron?
vitamin C, acid, meat
What strongly influences the absorption of non-heme iron?
enhacnes and inbitors
What is iron deficinecy anemia?
insufficient iron intake, caused by clood loss
What are symptoms of iron deficiency anemia?
Tired, out of breath, poor performance, and slow cognitive and social development
What groups are at high risk of iron deficiency anemia?
children, pregnant, menstruating women
What is the iron RDA for men >19 years old
8 mg
What is the iron RDA for women 19-50?
18 mg
What is the iron RDA for vegetarians?
doubled
How much more iron do atheles need?
30% more
What does excess iron cause?
gastrointestinal distress, iron poisoning
What does iron poisoning lead to?
unintentional death in children
What is zinc’s function?
Cofactor for over 900 enzymes
What is zinc required for?
almost every essential process in the body
What gropus are at risk of zinc deficiency?
alcoholics, vegetarians, elderly
How does alcohol affet zinc?
decreases absorption and increases excretion
What is copper essential for?
a variety of physiological processes in the body
What is copper’s function?
cofactor
What is selenium’s function?
cofactor
What is chromium’s function?
enhances action of insulin
What is fluoride important for?
- Hardens the enamel of our teeth
* Helps protect against dental caries
Why wouldn’t you want to have long-term excess intake of fluoride?
may have adverse effects on bone
What is manganese’s function?
Cofactor for enzymes
What does manganese help with?
antioxidant function, energy metabolism, bone development, and neurotransmitter production
What is molybdenum’s function?
Cofactor for four enzymes in metabolism