NDFS 1020 Chapter 9: Fat-soluble Vitamins
What 4 factors affect vitamin bioavailability?
1) Changes to the normal GI transit time (i.e. diarrhea) 2) Health conditions that affect absorption of fats 3) Food processing and preparation techniques 4) Source of the vitamin (most vitamins more bioavailable from natural food sources)
What are the functions of Vitamin A?
1) Vision (Cornea and Retina) 2) Protein synthesis, Growth, and Reproduction 3) Immunity 4) Bone health 5) Maintains epithelial tissue (i.e. skin)
What populations of people are more vulnerable to vitamin deficiencies?
Alcoholics, older adults, those hospitalized for long periods, anorexia nervosa, intestinal conditions that interfere with vitamin absorption, or have rare metabolic defects that increase their vitamin requirement
What are good sources of preformed Vitamin A, including retinyl esters?
Animal foods such as liver, butter, fish, fish oils, eggs
What are rich sources of beta-carotene, a crotenoid that the body can convert to Vitamin A?
Carrots, spinach and other leafy greens, pumpkin, sweet potatoes, broccoli, mangoes, and cantaloupe
What can happen if you take more than needed of a vitamin?
Cells are saturated with a vitamin and contain all they need and cannot accept additional amounts of the micronutrient. Continuing to take the vitamin can produce a toxicity disorder, because exposure to the excess micronutrient or its by-products can damage cells. Liver damage can also occur
Epithelial Cells
Cells that form protective tissues that line the body
Most fresh fruits and vegetables should be kept in plastic packaging and ______ until they are used.
Chilled
Vitamin
Complex organic molecule that regulates certain metabolic processes
Xerophthalmia
Condition affecting the eyes that results from vitamin A deficiency
Oseomalacia
Condition characterized by softening of the bones as a result of inadequate vitamin D status in adults; Symptom of muscle weakness
What factors contribute to the risk of Osteomalacia in adults?
Confined indoors or almost fully covered when outside during the day, kidney, liver, or intestinal diseases
______ helps protect Americans from developing the deficiency diseases associated with the lack of thiamin, riboflavin, niacin, folate, and iron.
Enrichment
What do many medical researchers suspect is responsible for promoting chemical changes in cells that ultimately lead to heart attack, stroke, cancer, Alzheimer's disease, and even the aging process?
Excess oxidation
What can destroy certain vitamins (Such as vitamin C)?
Exposure to excessive heat, alkaline substances (such as baking soda), light, and air
Age-related macular degeneration (AMD)
Eye disease resulting in changes in the macula of the eye, causing distorted vision
Results of clinical studies have provided support for taking vitamin A or beta-carotene supplements to reduce the risk of cardiovascular disease (CVD). (TRUE/FALSE)
False
Vitamin D is widespread in food. (TRUE/FALSE)
False (Vitamin D is NOT widespread in food)
Produce that is frozen immediately after being harvested and then properly stored is less nutritious as fresh produce. (TRUE/FALSE)
False (just as nutritious)
Vitamin K deficiencies often occur. (TRUE/FALSE)
False (rarely)
It is necessary to consume 100% of every vitamin each day. (TRUE/FALSE)
False; It is NOT necessary to consume 100% of every vitamin every day
People who have diseases that interfere with ______ absorption may become deficient in vitamin E, because dietary ______ enhances intestinal absorption of the micronutrient.
Fat
Adding a small amount of fat to low-fat foods can enhance the intestinal tract's ability to absorb ______- soluble vitamins in these food. Why?
Fat; Activates fat digestion processes
What are some factors associated with Vitamin D deficiency?
Female, black, Mexican-American; excess body fat; using electronic media or games for more than 4 hours daily, drinking milk less than once a week.
Cystic Fibrosis
Inherited respiratory disease caused by a defective gene that leads to overproduction of thick and sticky mucus; Unable to digest fat properly due to blockages forming in ducts that convey pancreatic enzymes to the small intestine, that reduce fat absorption. Often develop deficiencies of fat-soluble vitamins.
There appears to be a(n) ______ relationship between Vitamin K intake and risk for osteoporosis.
Inverse
Babies are generally born with low vitamin ___ stores, and a deficiency of the vitamin can occur soon after birth because of the newborn's immature GI tract.
K
The body stores very little Vitamin ___.
K
When vitamin __ is unavailable, blood-clotting factors are inactive, and the blood does not clot effectively.
K
Fat-soluble vitamins are chemically similar to what nutrient? How does this affect digestion and absorption?
Lipids; Processes that normally occur during fat digestion facilitate the absorption of fat-soluble vitamins
What determines the amount of time one needs to spend in the sun to form adequate amounts of Vitamin D?
Location, time of day and year, age, skin color
What carotenoids does the eye's macula contain?
Lutein, Zeaxanthin
Products made from vitamin E-rich plant oils, such as ______ and ______ dressings, also supply the micronutrient.
Margarine; Salad
What quick cooking methods that involve little contact between produce and water can conserve much of the vitamin content of the food?
Microwaving, steaming, and stir-frying
What foods are routinely fortified with Vitamin D?
Milk, ready-to-eat cereals, orange juice, margarine
What units are vitamins normally measured in?
Milligrams (mg), Micrograms (mcg or ug)
With vitamins, ______ is not necessarily better.
More
Vitamin A: Deficiency
NIGHT BLINDNESS XEROPHTHALMIA (total irreversible blindness) POOR GROWTH DRY SKIN INCREASED RISK OF INFECTION (i.e. measles)
Can the body make toxic levels of Vitamin D when exposed to sunlight?
No (because skin limits its production of 7-dehydrocholesterol)
Vitamin K: Toxcity
Not Common
Water-Soluble Vitamin are usually ____ ______ in the body and must be ______ more often.
Not stored; Replenished
Vitamin A: Sources
Orange, Yellow, and Dark Green VEGETABLES (pumpkin, squash, spinach, sweet potatoes, broccoli, carrots) FRUIT (mangos, cantaloupe) MILK
An atom or molecule that loses one or more electrons has been ______.
Oxidized
Antioxidants
Substance that gives up electrons to free radicals to protect cells
Oxidizing Agent or Oxidant
Substance that removes electrons from atoms or molecules
Free Radical
Substance with an unpaired electron; Highly reactive; Chemically unstable; Can damage or destroy proteins, fatty acids, and DNA by removing some of their electrons
What are some rich food sources of Vitamin E?
Sunflower seeds, almonds, plant oils, especially sunflower, safflower, canola, and olive oils, fish, whole grains, nuts, seeds, certain vegetables.
What does the body depend on to synthesize Vitamin D?
Sunlight
Multivitamin-Multimineral Supplement
Supplement containing two or more vitamins and minerals
What are the functions of Vitamin K?
Synthesis of blood-clotting, proteins, and bone proteins
The natural form of vitamin E has more biological activity, that is, it produces more effects in the body, than ______ vitamin E.
Synthetic
Vitamin E: Toxicity
Taking Vitamin E dietary supplements can interfere with the blood-clotting function of Vitamin K and cause significant and/or uncontrolled bleeding (hemorrhaging)
Frozen fruits and vegetables need to be cooked without ______ to conserve much of their vitamin content.
Thawing
Today, severe ______ deficiencies are uncommon in the United States, thanks in part to modern food preservation practices, food enrichment and fortification, and the year-round, widespread availability of fresh fruits and vegetables from other countries.
Vitamin
What vitamin plays a role in the production and activity of white blood cells?
Vitamin A
What vitamin acts as a hormone?
Vitamin D
What vitamin is called the "Sunshine Vitamin?"
Vitamin D (exposure to sunlight activates the vitamin D pre-cursor made in the body
Rickets
Vitamin D-deficiency disorder in children resulting in improper bone growth
Although many American adults do not consume recommended amounts of vitamin ___, its deficiency is rare.
Vitamin E
What vitamin can interfere with blood-clotting medication (Coumadin)?
Vitamin K
Bacteria that reside in the lower intestinal tract produce certain ______, particularly biotin and vitamin K, which can be absorbed to some extent.
Vitamins
Fat-soluble Vitamins
Vitamins A, D, E, and K
What can you do to reduce vitamin losses in fruits and vegetables?
Wait to trim, peel, and cut until just before eating or serving them
What 2 criteria do vitamins have to meet?
1) Body cannot synthesize the compound or make enough to maintain good health (it is an essential nutrient); 2) Compound naturally occurs in commonly eaten foods
What are the functions of Vitamin D?
1) Bone health: Regulates phosphorus and blood calcium concentration (Pulls Ca from Bones, Kidneys, and GI Tract) 2) Cell differentiation 3) Insulin secretion 4) Regulation of blood pressure 5) Immune system
What are the functions of Vitamin E?
1) Antioxidant (protects polyunsaturated fatty acids in cell membranes from being damaged by free radicals) 2) Wound healing 3) Cell membrane integrity 4) Heart health (prevent atherosclerosis)
When vitamin D is lacking, the intestine absorbs only ___ to ___% of the calcium in foods; with the vitamin, intestinal absorption of dietary calcium increases to 30 to 80%
10 to 15%
Healthy children, especially breastfed infants, should consume how much Vitamin D supplement per day soon after birth through adolescence?
400 IU of vitamin D per day
Approximately __% of American adults had low blood levels of vitamin D.
41%
All cells in the body in vitamin __ to develop and function properly.
A
What vitamins are deficient in people with Cystic Fibrosis?
A, D
Americans consume less than recommended amounts of vitamins __, __, __, and K
A;D;E
Vitamin E: Functions
ANTIOXIDANT (helps protect cell membranes and prevents free-radical damage in body cells and tissues) WOUND HEALING DECREASES OXIDATION Improves IMMUNITY Helps maintain NERVOUS TISSUE
Vitamin K: Functions
BLOOD CLOTTING (needed to produce 4 blood-clotting factors) BONE HEALTH (functions as a co-factor for an enzyme that produces osteocalcin - a protein that's essential for bone-building and mineralization)
What is the precursor for active Vitamin A?
Beta-Carotene (causes a yellow/orange pigmentation)
To prevent ______-______ deficiency from developing during infancy, newborns generally receive a single injection of vitamin K immediately after birth.
Blood-clotting
Where does the body store Vitamin E?
Body fat, skeletal muscle, liver
Young children that are more likely to develop Rickets are:
Breastfed, dark skin, minimal sunlight exposure, little or no vitamin D intake
Vitamin A: Toxicity
CAROTENEMIA (orange-colored skin, usually harmless) BIRTH DEFECTS BONE FRACTURES LIVER DAMAGE Headaches, Nausea/Vomiting
What is another name for Vitamin D?
Calciferol
Findings of observational studies suggest an association between eating diets rich in fruits and vegetables and lower risk of what disease? Possibly due to what?
Cancers, heart disease, age-related macular degeneration; Beta-carotene and antioxidant carotenoids.
Diets supplying high amounts of ______ (beta-carotene, lutein, and zeaxanthin) may lower the risk of AMD.
Carotenoids
The body can synthesize vitamin ___, niacin, and ______ under certain conditions.
D; Choline
What part of vegetable greens generally contain more vitamins?
Darker leaves (contain more vitamins than paler inner leaves or stems)
Biological Activity
Describes vitamin's degree of potency or effects in the body
Use of vitamin ___ supplements has been associated with an increased risk of hemorrhagic stroke.
E
Enrichment does not replace the vitamin __, vitamin __, magnesium, several other micronutrients, and ______ that were naturally present in the unrefined grains.
E; B-6; Fiber
What foods naturally contain Vitamin D?
Fish liver oils and fatty fish (salmon, herring, catfish)
Vitamin K: Sources
GREEN LEAFY VEGETABLES (kale, spinach, broccoli, green beans, turnip greens, salad greens, cabbage) BEANS & SOYBEANS VEGETABLE OILS Healthy GI Tract (microflora in gut can synthesize up to 50% of needs)
What are some major food sources of Vitamin K?
Green leafy vegetables, kale, turnip greens, salad greens, cabbage, spinach, broccoli, green beans, soybean and canola oils, margarine, salad dressing
Vitamin E: Deficiency
HEMOLYSIS (breakage) of Red Blood Cells (RBC) ANEMIA DECREASED MUSCLE COORDINATION and loss of neuromuscular control Damage to nerves and/or nervous system Compromised IMMUNITY
Vitamin K: Deficiency
HEMORRHAGING (severe and uncontrolled bleeding) HEMORRHAGIC DISEASE (rare but may occur in infants) Increased risk of HIP FRACTURES
Vitamin D: Toxicity
HYPERCALCEMIA (calcium deposits in soft tissue) Increased risk of KIDNEY STONES (in some cases) POOR GROWTH
A standard dose of Vitamin K is given to babies at birth to prevent what disease?
Hemorrhagic Disease (infants have a sterile gut and don't produce Vitamin K)
Vitamin absorption tends to increase when the body's needs for the micronutrients are also ______ than usual.
Higher
Night Blindness
Inability to see in dim light; Can occur if retinol is unavailable; May be early sign of vitamin A deficiency
Precursor
Inactive form of a vitamin; Can be activated in the body (ie Beta-Carotene, Pre-Vitamin D3)
What is the most reliable sign of vitamin K deficiency?
Increase in the time it takes for blood to clot
When does the body's requirements for vitamins generally increase?
Periods of growth (infancy/adolescence), pregnancy, breastfeeding
Blood contains inactive clotting factors and cell fragments called ______ that are necessary for blood clotting to occur. When a blood vessel is cut, blood in the injured area undergoes a complex series of steps to form a clot that stops the bleeding. A clot is comprised of strands of the protein ______ that traps blood cells, forming a mesh. The liver synthesizes several blood-clotting factors, and the organ needs vitamin ___ to produce four of them properly.
Platelets; Fibrin; K
Who are at risk of Vitamin A deficiency?
Preschool children who do not eat enough vegetables, low-income urban residents, older adults, people with severe alcoholism, fat malabsorption, or liver diseases
Vitamin D: Deficiency
RICKETS in children (soft bones, bowed legs, bone deformities) OSTEOMALACIA in adults (bone pain due to soft bones) OSTEOPOROSIS in elderly adults (severe bone loss) DECREASED IMMUNITY IMPAIRED GROWTH
Vitamin D: Functions
Regulates CALCIUM absorption (from the GI Tract, Kidneys, and Bones) and metabolism (maintains normal blood calcium levels and manages storage of calcium in bones) BONE STRENGTH IMMUNE FUNCTION NEUROMUSCULAR FUNCTION GENE REGULATION DECREASES INFLAMMATION
What are the other names for Vitamin A?
Retinol, Retinal, Retinoic Acid
Tomatoes, bananas, and garlic should be stored at ______ temperature.
Room
Vitamin D: Sources
SUNLIGHT (or other source of UV light) DAIRY PRODUCTS (milk, yogurt, butter) FISH (salmon, herring, tuna) fortified BREAKFAST CEREALS EGGS
Vitamins are needed to (Large/Small) amounts compared to Macronutrients.
Small
What is the primary site of vitamin absorption?
Small Intestine
Signs of Vitamin D toxicity
Small intestine absorbs too much calcium from foods and is deposited in the kidneys, heart, and blood vessels. Calcium deposits can interfere with cells' ability to function and cause cellular death; Muscular weakness, loss of appetite, diarrhea, vomiting, mental confusion
How can you ensure that fresh produce retain their vitamin content better?
Store at temperatures near freezing, in high humidity, and away from air
Fat-Soluble Vitamins are ______ in the body and ______ is more likely.
Stored; Toxicity
Bioavailability of Vitamins
The amount of that vitamin that is actually available for use by the body
How can fat-soluble vitamins cause a toxicity in the body?
The body has more difficulty eliminating excess fat-soluble vitamins because they do not dissolve in watery substances such as urine. The body then stores extra fat-soluble vitamins, primarily in the liver and in adipose tissue. Over time, these vitamins can accumulate and cause toxicity.
Why don't water-soluble vitamins generally cause a toxicity in the body?
The body stores only limited amounts of most water-soluble vitamins (vitamin B-12/exception), and kidneys can filter excesses of water-soluble vitamins from the bloodstream and eliminate them in urine.
Vitamin E: Sources
VEGETABLE OILS (sunflower, safflower, canola, and olive oils) NUTS & SEEDS (sunflower seeds, almonds) WHEAT GERM FISH Green leafy VEGETABLES Fortified BREAKFAST CEREALS
Vitamin A: Function
VISION (healthy cornea and retina) EPITHELIAL TISSUE (healthy skin + cells that line digestive, respiratory, and reproductive tracts) GROWTH BONE REMODELING IMMUNITY (needed for the production of WBC)
Water-soluble Vitamins
Thiamin, riboflavin, niacin, vitamin B-6, pantothenic acid, folate, biotin, vitamin B-12, and vitamin C
Vitamin K deficiency can develop in what type of people?
Those who have liver diseases, conditions that impair fat absorption (cystic fibrosis), long-term antibiotic therapy
What is Vitamin E also known as?
Tocopherol
Keratin
Tough protein found in hair, nails, and the outermost layers of skin
According to the Food and Drug Administration (FDA), microwave cooking does not reduce the nutrient content of foods any more than do conventional cooking methods. (TRUE/FALSE)
True
Eating carrots and other foods that are high in vitamin A and beta-carotene will help improve your vision. (TRUE/FALSE)
True
In general, vitamins regulate a variety of body processes, including those involved in cell division and development as well as the growth and maintenance of tissues. (TRUE/FALSE)
True
Many Americans do not consume enough vitamin D to meet the RDA. (TRUE/FALSE)
True
Most vitamins are more bioavailable from natural food sources. (TRUE/FALSE)
True
Regardless of whether a particular vitamin is naturally found in foods or synthesized in a laboratory, it generally has the same chemical structure and works equally well in the body. (TRUE/FALSE)
True
Vitamin E may reduce the risk of Alzheimer's, but does not enhance sexual performance, prevent aging, or cure Muscular Dystrophy or Parkinson's Disease. (TRUE/FALSE)
True
Vitamins & minerals are absorbed as whole units, Not broken down like the macronutrients. (TRUE/FALSE)
True
Vitamins and minerals are found in ALL food groups. (TRUE/FALSE)
True
Vitamins do NOT provide Kcals, but are needed to utlize energy from carbohydrates, lipids, and protein. (TRUE/FALSE)
True
It is unlikely that any vitamins still need to be discovered. (TRUE/FALSE)
True (Infant formula and liquid formulas provide necessary vitamins for life)
Vitamins are NOT a source of energy (TRUE/FALSE)
True; Although many do participate in chemical reaction to release energy from other nutrients
Some free radical formation in the body is necessary and provides some benefits. (TRUE/FALSE)
True; Free radical stimulate normal cell growth and division
Why is it important to know the difference between fat- and water-soluble vitamins?
Water-soluble vitamins are not as likely to be toxic as fat-soluble vitamins
Carotenemia
Yellowing of the skin that results from excess beta-carotene in the body; Mostly harmless