Ch 11 Nutrition The Fat-Soluble Vitamins: A, D, E, and K
Vitamin K is essential for synthesis of prothrombin and several other clotting factors. Blood clots are formed by a cascade of reactions, with each step creating a compound that activates the next step.
Blood clotting VITAMIN K Vitamin K is essential for synthesis of ______ and several other _______ factors. Blood clots are formed by a cascade of reactions, with each step creating a compound that activates the next step.
•Damage to cellular DNA -Antioxidants may protect DNA from this damage -Inverse relationship with vegetable intake •Healthy diet with abundant fruits and vegetables -Protect against certain types of cancer •Vitamin E -Supplement cautions (conflicting evidence concerning vit E and cancer, page 354)
Defending Against Cancer •Damage to cellular _____ -_________ may protect DNA from this damage -Inverse relationship with ______ intake •Healthy diet with abundant _____ and ____________ -Protect against certain types of _______ •Vitamin E -Supplement cautions (conflicting evidence concerning vit E and ______
•System of enzymes against oxidants -Uses copper, selenium, manganese, and zinc •Antioxidant vitamins -Vitamin E §Defends body lipids -Beta-carotene §Defends lipid membranes -Vitamin C §Protects skin and blood fluid
Defending Against Free Radicals •System of enzymes against oxidants -Uses copper, selenium, manganese, and zinc •Antioxidant vitamins -Vitamin E Defends ______ lipids -Beta-carotene Defends ______ membranes -Vitamin C Protects _____ and _____ fluid
•Oxidized LDL scenario -Accelerate formation of artery-clogging plaques -Additional changes in arterial walls §Changing their structure and function •Vitamin E -Protect against hypertension and heart disease -Defends against LDL oxidation •Vitamin C -Protect against LDL oxidation •Unclear if supplements provide same benefit as food
Defending Against Heart Disease •Oxidized LDL scenario -Accelerate formation of ________-clogging plaques -Additional changes in _______ walls Changing their structure and function •Vitamin E -Protect against _______ and ________ disease -Defends against ______ oxidation •Vitamin C -Protect against _________ oxidation •Unclear if supplements provide same benefit as food
Bile lymphatic system
Fat soluble vitamins require ______ for their digestion, and absorption. Upon absorption, fat soluble vitamins travel through the _________- before entering the blood stream.
1. Bile 2. Lymphatic 3. Stored 4. Excreted; toxicity
Fat-soluble vitamins differ from water-soluble vitamins in that: 1.They require ____ for digestion and absorption. 2.They travel through the _____ system. 3.Excesses are ______ in the liver and adipose tissues. 4.They are not readily ______. This increases risk of _______.
•Dietary strategies for preventing heart disease -Use unsaturated instead of saturated or trans fats -Select foods rich in omega-3 fatty acids -Diet high in fruits, vegetables, nuts, and whole grains, and low in refined grain products •Supplement use -Research outcome: provides no benefit §May increase risk → acting as prooxidants
Foods, Supplements, or Both? •Dietary strategies for preventing heart disease -Use _______- instead of ______ or _______- fats -Select foods rich in ____-____ fatty acids -Diet high in ______, ______, ______, and whole ______, and low in refined ______ products •Supplement use -Research outcome: provides no benefit May increase risk → acting as prooxidants
Answer: 1. Electron 2. Does 3. Antioxidants; oxidative Explanation: Environmental factors including pollution generate free radicals. Antioxidants don't become free radicals.
Free Radicals 1.Free radicals contain one or more unpaired _____. 2.The body does/does not produce free radicals. 3._______ neutralize free radicals. This prevents ____ stress.
•Oxidative stress causative factor in: -Reduced cognitive performance, cancer, heart disease, arthritis, cataracts, diabetes •Body's natural defenses and repair systems -Not 100 percent effective -Less effective with age
Free Radicals and Disease •Oxidative stress causative factor in: -Reduced _______ performance, _________, _________ disease, ________, _______, ________ •Body's _______ defenses and repair systems -Not 100 percent effective -Less effective with _______
Significant sources sunlight, milk, chocolate, beef, egg yolks, fatty fish
Good sources of VitD (6)
Answer: 1. Keratin; dry 2. Goblet; mucus; digestion Explanation: Keratin is the hard, inflexible protein commonly found in nails and hair. Keratinization increases the risk of infection of the respiratory tract, GI tract, urinary tract, vagina, and inner ear.
Keratinization. --VIT A DEFICIENCY 1.Epithelial cells of the skin change shape and secrete the protein _____. As a result, skin becomes ____ and scaly. 2.In the GI tract, ____ cells diminish. This limits the secretion of _____. This impedes _____ and absorption, often worsening malnutrition.
•Toxicities are possible •Functions of fat-soluble vitamins together -Vitamins E and A §Oxidation, absorption, and storage -Vitamins A, D, and K §Bone growth and remodeling -Vitamins E and K §Blood clotting
The Fat-Soluble Vitamins: A Summary •_________ are possible •Functions of fat-soluble vitamins together -Vitamins ____ and _______ do oxidation, absorption, and storage -Vitamins ___, ___, and ____ do bone growth and remodeling -Vitamins ___ and ___do Blood clotting
TRUE!! Explanation: Exposing hands, face, and arms on a clear summer day for 5 to 10 minutes two to three times a week is often sufficient.
Vit D Most sunscreens reduce the synthesis of vitamin D. a)True b)False
•Two subgroups: tocopherols and tocotrienols -Each contains four members: alpha, beta, gamma, and delta §Position of methyl group -Only alpha-tocopherol maintained in the body •Antioxidant -Stops chain reaction of free radicals §Protects cells and their membranes oPrevents oxidation of poly unsaturated fatty acids (PUFAs) §Heart disease and protection of LDLs
Vit E •Two subgroups: tocopherols and tocotrienols -Each contains four members: _____, _____, ________, and ______ Position of methyl group -Only alpha-tocopherol maintained in the body •Antioxidant -Stops chain reaction of free radicals Protects cells and their membranes oPrevents oxidation of poly unsaturated fatty acids (PUFAs) Heart disease and protection of LDLs
source vegetable oils, dark leafy greens, whole grains, liver, egg yolks
Vit E sources (5)
•Large problem in developing countries •Vitamin A status -Depends on adequacy of Vit. A stores, -90 percent in liver -Protein status •Consequences of deficiency -Risk of infectious diseases -Night blindness and blindness §Treatment -Death
Vitamin A Deficiency •Large problem in developing ______ •Vitamin A status -Depends on adequacy of _______ ____ ________, -__________ percent in liver -___________ status •Consequences of deficiency -Risk of __________ diseases -Night _________ and ________ Treatment -Death
a)Retinal (central role in vision): Active in vision b)Retinol --> Supports reproduction and is the major transport and storage form c) Retinoic acid --> Regulates cell differentiation, growth, and embryonic development Explanation: Vitamin A is a versatile vitamin that regulates the expression of hundreds of genes.
Vitamin A Roles in the Body a)________: Active in vision b)________: Supports reproduction and is the major transport and storage form c) _____: Regulates cell differentiation, growth, and embryonic development
Answer: 1. Skin; mucous membranes 2. Mucous
Vitamin A and Cell Differentiation 1.Epithelial cells on the outside of the body form ____. They also line the inside of the body, forming ______(2 words). 2.Goblet cells synthesize and secrete _____.
•Maintains clear cornea •Converts light energy to nerve impulses in the retina -Photosensitive cells contain rhodopsin •Repeated small losses of retinal -Need for replenishment
Vitamin A and Vision •Maintains clear _____ •Converts ______ energy to _____ impulses in the retina -Photosensitive cells contain _______ •Repeated small losses of _______ -Need for _________
1. tomato juice 2.carrots 3.broccoli 4.cornflakes 5.beef liver 6. sweet potatoes 7.mango
Vitamin A in Selected Foods (7)
•Sperm development •Normal fetal development •Growth of children (decrease in Vitamin, Kids fail to grow) -Bone remodeling •Antioxidant -Beta-carotene
Vitamin A's Role in Reproduction and Growth •______ development •Normal ______ development •Growth of ________- (decrease in Vitamin, Kids fail to grow) -________ remodeling •Antioxidant -Beta-carotene
Vitamin A-Deficiency Symptom—The Rough Skin of Keratinization
Vitamin A-Deficiency Symptom—The Rough Skin of _____
Answer: 1. Is not. The body can synthesize vitamin D via exposure to sunlight from a precursor the body makes from cholesterol. 2. Activated 3. Liver; kidneys
Vitamin D 1.Vitamin D is/is not an essential nutrient. Explain. 2.Vitamin D requires two hydroxylation reactions to occur for it to become ______. 3.These reactions occur first in the _____, then in the ____.
Answer: 1. 16 2. Dark skin, breastfeeding without supplementation, lack of sunlight, not consuming fortified milk 3. Calcium Explanation: Vitamin D deficiency in adolescents may prevent reaching peak bone mass.
Vitamin D Deficiency 1.An estimated ___ percent of Americans have low blood levels of vitamin D. 2.List four factors that contribute to vitamin D deficiency. 3.A vitamin D deficiency subsequently causes a _____ deficiency. 4.Do Vitamin D Supplements Help with Diabetes, Weight Loss, and Blood Pressure?
Answer: 1. Oily fish, egg yolks, fortified milk 2. Too low 3. Cannot Explanation: Meeting recommendations are difficult without sunlight, supplementation, or fortification.Vitamin D production varies with skin color, latitude, season, and time of day
Vitamin D Recommendations 1.There are few food sources of vitamin D, fish, milk, egg yolks 2.The recommendations for vitamin D may be too high/ too low. 3.Toxicity can/cannot occur from sun exposure.
•Most likely of the vitamins to have toxic effects -Supplements •Raises blood calcium concentrations -Forms stones in soft tissues §Kidneys -May harden blood vessels §Can cause death
Vitamin D Toxicity •Most likely of the vitamins to have toxic effects -Supplements •Raises ____ _______ concentrations -Forms _______ in soft tissues Kidneys -May _______ blood vessels Can cause _______
Answer: 1. Hormone 2. Bones; phosphorus 3. Cognitive decline Explanation: Vitamin D may also regulate adipose cells to influence obesity development. Research shows vitamin D may be protective against heart disease, inflammation, brain disorders, type 2 diabetes, and more.
Vitamin D's Roles in the Body 1.The active form of vitamin D is a ______. 2.Vitamin D is essential for making and maintaining ____. Vitamin D assists in the absorption of calcium and _____. 3.In brain and nerve cells, vitamin D may protect against ________ (2 words).
Answer: 1. Alpha-tocopherol 2. Vegetable 3. Oxidation Explanation: Vegetable oils, margarine, seeds, and nuts are good sources of vitamin E.
Vitamin E Recommendations 1.The RDA is based on the ______-_______ form only. 2.Vitamin E is widespread in foods. Much of dietary vitamin E comes from _____ oils or foods containing them. 3.Vitamin E is destroyed by _____ and heat, therefore fresh foods are preferable sources.
Secondary deficiency: Antibiotics kill off vitamin K-producing bacteria Primary deficiency Inadequate dietary intake Is rare Antibiotics kill off vitamin K-producing bacteria: If bile production fails Infants: Sterile gut, no vitamin K-producing bacteria Explanation: Intestinal bacteria produce vitamin K. In newborns, it takes weeks to establish those bacteria. A vitamin K shot is given at birth. All babies are born with low levels of vitamin K, an important factor in helping a baby's blood clot. We give all healthy newborns a vitamin K shot shortly after delivery
Vitamin K Deficiency __________ Antibiotics kill off vitamin K-producing bacteria _________Inadequate dietary intake. Is rare __________If bile production fails ___________Sterile gut, no vitamin K-producing bacteria
Answer: 1. Synthesized by intestinal bacteria. However, amount is insufficient to meet needs, and bioavailability is limited. 2. Leafy greens including kale and spinach. Fruits such as avocado and kiwi. Vegetable oils.
Vitamin K Sources ** 1.Explain the non-food source of vitamin K and comment on its sufficiency. 2.List three food sources of vitamin K.
•Vitamin A -First fat-soluble vitamin recognized -Precursor: beta-carotene •Three different forms -Retinol, retinal, and retinoic acid Conversion to other forms •Absorption and conversion -Beta-carotene
•Vitamin A -First ____-______ vitamin recognized -Precursor: _____-________ •Three different forms -________, _______, and ______ acid Conversion to other forms •Absorption and conversion -Beta-carotene