Lesson 7: Vitamins Flashcards
(124 cards)
What do we call organic essential nutrients required in tiny amount to perform specific functions that promote growth, reproduction or the maintenance of health and life?
Vitamins
What do we call inorganic essential nutrients required in varying amounts that function primarily as structural components or regulators of body processes?
Minerals
Vitamins do not yield usable energy when metabolized. Therefore, what is their role?
Assist the enzymes that participate in the release of energy from carbohydrates, fats and proteins.
Can vitamins be destroyed?
Yes
In what units do we measure vitamins?
Micrograms (pg) or milligrams (mg)
How are vitamins similar to the energy-yielding nutrients?
Vital to life
Organic
Available from foods
Are are minerals different from vitamins?
They have an inorganic chemical nature
They always retain their chemical identity
Can minerals taken in excess be toxic?
Yes
Can vitamins taken in excess be toxic?
Yes, fat-soluble vitamins
What is “the rate at and the extent to which a nutrient is absorbed and used?”
Bioavailability
What does determining bioavailability of vitamins and minerals depend on?
Food preparation
Efficiency of digestion
Previous nutrient intake
Source of the nutrient (synthetic, naturally occurring)
Some of the vitamins are available from foods in inactive forms before entering the body and converted to the active form of the vitamin. This inactive forms are called___________.
Precursors
Name 4 ways to minimize vitamin losses.
- refrigerate most fruits and vegetables
- store fruits and vegetables that have been cut in airtight wrappers
- rinse fruits and vegetables before cutting
- use a microwave oven or steam vegetables during cooking in a small amount of water
How are water-soluble vitamins absorbed?
Move directly into the blood. Once in the blood, they travel freely
How are fat-soluble vitamins absorbed?
They must first enter the lymph, then the blood. Once in the blood they require transport proteins.
Why do large excesses of fat-soluble vitamins overwhelm the system?
They tend to remain in fat storage sites in the body rather than being excreted, so are more likely to reach toxic levels when consumed in excess.
The presence or absence of one vitamin or mineral can affect another’s absorption, metabolism and excretion.Give 3 examples of interactions
- Folate and B12 can mutually enhance absorption and perform metabolic roles
- Sodium and Calcium cause both to be excreted when sodium intakes are high .
- Phosphorus binds to magnesium in the GI tract, so magnesium absorption is limited when phosphorus intakes are high.
What are the water-soluble vitamins?
Thiamin Riboflavin Niacin Pantothenic Acid Biotin B6 B12 Folate Vitamin C
What are the fat-soluble vitamins?
Vitamin A
Vitamin D
Vitamin E
Vitamin K
What are vitamins made up of?
Carbon, Hydrogen, Oxygen, sometimes Nitrogen and Sulphur
Where do natural sources of vitamins come from?
Plants, Animals, fungi and bacteria
What do we mean by “synthetic” sources of vitamins?
Chemists put bacteria/microbes to work in the laboratory to synthesize vitamins. Used in the enrichment and fortification of foods.
What do we call the addition of vitamins and minerals to foods products to replace those lost during processing (refinement) so that the food will meet a specified standard?
Enrichment
What do we call the addition of supplementary nutrients to food that were either not originally present or present in insignificant amount, to reduce risk of disease at the population level?
Fortification