Chapter 8: Vitamins Flashcards
What are vitamins?
Essential nutrients.
Substances found in foods that can be converted into an active form once they are absorbed.
What is bioavailability?
The degree to which a nutrient is absorbed from foods.
Which vitamins are classified as fat-soluble?
A, D, E, K
What sources are rich in fat-soluble vitamins?
Fortified milk, oils
Which vitamins are classified as water-soluble?
B vitamins and C
What is a key characteristic of water-soluble vitamins?
Not stored in the body; excess is excreted.
Where are most water-soluble vitamins absorbed?
Upper part of the small intestine.
What happens to excess water-soluble vitamins in the body?
Excess is excreted.
Fill in the blank: Fat-soluble vitamins are _______ in the body.
stored
Fill in the blank: Water-soluble vitamins are absorbed with _______.
water
What is the risk associated with excess intake of fat-soluble vitamins?
Can be toxic in high doses.
What is the primary transport mechanism for fat-soluble vitamins?
Packed in micelles and chylomicrons.
True or False: Water-soluble vitamins can be toxic in high doses.
False
What is one way to improve the bioavailability of vitamins?
Reduce cooking time.
Also, keeping food stored in a cool place and add little water when cooking.
What is the main storage tissue for fat-soluble vitamins?
Adipose tissue
Fill in the blank: ____ vitamins are co-enzymes.
B.
What antioxidant vitamins are important for neutralizing free-radicals to counteract oxidation?
Vitamins (A,C,E) and beta carotene (vitamin A).
Taking megadose vitamin supplements can cause what toxicity?
Hypervitaminosis.
What is a vitamin has preformed vitamins that do not need to undergo conversion?
Vitamin A.
Preformed foods vs provitamin food examples for vitamin A?
Animal products found in preformed, vegetables like carrots, spinach, sweet potatoes, and pumpkin in proformed options.
When absorbed, where do water soluble vitamins go?
Bloodstream.
Where are fat soluble vitamins stored?
Liver, fat, and muscle tissue
What is the primary function of Vitamin A?
Healthy vision, cell differentiation, reproduction, and immunity
Vitamin A is important for various bodily functions including maintaining healthy skin and mucous membranes.
What two deficiencies can result from a lack of Vitamin A?
Night blindness and Xerophthalmia (permanent damage to the cornea)
Xerophthalmia is characterized by dry eyes and can lead to blindness if untreated.
What is the toxicity risk associated with excessive preformed Vitamin A?
Can accumulate to toxic levels, leading to liver damage or death
Carotenoids are non-toxic but can cause skin discoloration.
What are the two primary function of Vitamin E?
Powerful antioxidant that prevents free radical damage and anticoagulant.
Vitamin E is fat-soluble and essential for immune function.
What is the primary function of Vitamin D?
Regulates bone health and may prevent some cancers
Vitamin D is fat-soluble and essential for calcium absorption.
What are the potential health issues associated with Vitamin D deficiency?
Rickets in children and osteomalacia in adults
Rickets causes inadequate mineralization of bones, leading to bowed legs.
What is the toxicity associated with excessive Vitamin D intake?
Hypervitaminosis D, leading to damaging calcium deposits in kidneys, lungs, and heart
Symptoms may include nausea, weakness, and kidney damage.
What is the primary function of Thiamin (Vitamin B1)?
Transmission of nerve impulses and breakdown of alcohol in the body)
What deficiency disease is associated with Thiamin?
Beriberi
Beriberi can lead to severe neurological and cardiovascular problems.
What is the toxicity risk associated with Thiamin?
No known toxicity, no upper limit set
Thiamin is generally considered safe even at high doses.
What food sources are rich in Vitamin K?
Fortified dairy, fortified cereals, fatty fish, and green leafy vegetables
Vitamin K is also produced by bacteria in the gut.
What is the concern from supplements of vitamins E megadoses?
Increased risk of hemorrhages.
What can destroy vitamin E?
High heat.
Where is vitamin E found in food?
Vegetable oils, nuts, seeds, fortified cereals, some leafy vegetables.
What is vitamin K essential for?
Blood clotting.
People who are taking blood thinners need to do what for vitamin K?
Stay consistent with the amount they are receiving.
What are the two forms of vitamin K?
Menaquinone (made by bacteria in the gut)
Phylloquinone (found in green plants, like K for Kale)
Fill in the blank: Wernicke-Korsakoff syndrome cause by deficiency in _____ vitamin, causes progressive brain damage from _______ abuse.
Thiamin. Chronic alcohol abuse.
Can be mistaken for intoxication.
Is there a toxicity level to Thiamin?
No
What are 2 food sources of thiamin?
Enriched and whole grains, pork.
What are the deficiency symptoms of Riboflavin?
Sore throat, swelling inside mouth, inflamed and purplish-red tongue (glossitis), dry and scaly lips
What are the functions of Niacin?
- Synthesize fat and cholesterol
- Keep skin cells and digestive system healthy
What are the results of Niacin deficiency known as?
The ‘four D’s’. Dermatitis, diarrhea, dementia, death.
What is a key function of Vitamin B6?
Metabolize fats and carbs, and break down glycogen
What food sources are rich in Niacin?
- Meat
- Fish
- Poultry
- Fortified cereals
- Enriched whole-grain breads
What are the four functions of Folate?
- Create/maintain new cells, especially red blood cells.
- Help body use amino acids
- Reduces risk of some cancers
*Prevents birth defects.
What deficiency can result from a lack of Vitamin B12?
Pernicious anemia because of lack of IF in stomach and macrocytic anemia because it interferes with folate.
What is required for Vitamin B12 absorption?
Intrinsic factor (IF) from the stomach to be absorbed and stored in the liver.
What are some food sources of Folate?
- Enriched grains (rice, pasta, breads, cereals)
- Legumes
- Broccoli
- Asparagus
- Leafy greens such as spinach
What can excessive folic acid intake mask?
Vitamin B12 deficiency anemia
What does the name ‘Folate’ refer to?
It is similar to ‘foliage’, meaning it is found in foods of plant origin
Fill in the blank: High amounts of riboflavin can turn your urine bright ________.
Bright yellow
Main function of riboflavin is?
Important for energy metabolism.
Fill in the blank: riboflavin is sensitive to_______ so it must be stored in opaque containers.
UV light.
Pellagra is a deficiency disease linked to the vitamin _______.
Niacin.
Niacin is considered a drug due to high levels you can intake in supplements, high doses prescribed decrease ______ and triglycerides, and increase ______.
LDL and HDL.
High protein diets have high amounts of _______, which make tryptophan (amino acids).
Protein
Vitamin B6 deficiency risk is for people who abuse alcohol, why?
Alcohol causes the body to lose B6. Along with poor diet.
UL is set at 100mg/day to prevent what in vitamin B6?
Potential permanent nerve damage.
What food sources is vitamin B6 found in?
Meat, fish, poultry, fortified, cereals, nuts, legumes, peanut butter, many fruits and vegetables.
True or False? Deficiency in folate can cause neural tube defects in pregnancies and macrocytic anemia in adults.
True
What food sources is vitamin B12 found?
Only found in animal foods.
Three functions of vitamin B12?
To make DNA, use certain fatty acids and amino acids, and healthy nerves and cells especially red blood cells.
What is the additional Vitamin C requirement for smokers?
35+ mg/day
What are three functions of Vitamin C?
Needed to make collagen.
Antioxidant
Helps to maintain a strong immune system.
How does Vitamin C help with iron absorption?
Helps absorb iron from plant foods
What is a key benefit of Vitamin C for the immune system?
Helps maintain a strong immune system
What is the deficiency disease caused by lack of Vitamin C?
Scurvy
What are some symptoms of Vitamin C deficiency?
Bleeding gums, rash, non-healing wounds
What are potential toxic effects of excessive Vitamin C intake?
Intestinal upset, possible increased risk of kidney stones
List three food sources of Vitamin C other than oranges.
- Tomatoes
- Peppers
- Broccoli
