Nutrition Introdution Flashcards
Define nutrition
Nutrition is utilization of foods by living organisms for growth, reproduction and maintenane of health.
Define nutrients.
Nutrients are substances and qualities of food that are required for life, and for growth, maintenance, and repair of body tissues.
Nutrients are divided into two broad groups known as
Organic compounds and inorganic compounds
Some nutrients are classes of substances, give examples of five:
Fiber, energy, omega-3 fatty acids, vitamin E, vitamin A
Define fiber as a nutrient
Many subtanes that are variably water soluble and fermentable.
Define energy as a nutrient
Chemical bond energy in organic susbtances
omega-3 fatty acids include:
Eicosapentaenoic acid (EPA), docosahexaneoic acid DHA
nutrients classified under Vitamin E include:
tocopherols and tocotrienols
Describe nutrients classified under vitamin A:
substances with retinol-like activity in animals (ex. carotene)
What are the two general functions of nutrients?
- Supply energy for metabolic processes
2. Substrate for body structural and functional substances
Define an essential nutrient.
An essential nutrient is a substance that is required and cannot be synthesized or synthesized in amounts sufficient to meet animal needs.
Define a conditionally-essential nutrient.
A substance that is essential under certain conitions, such as a physioligcal stage (choline for growth) or a disease stage (vitamin C during liver insufficiency)
List the essential nutrients for most animals.
- Water - greatest mass of daily intake
- Energy - derived from protein, fat, and carbs
- Amino acids - 20 in diet, about half are essential
- Minerals - macrominerls and trace- or micro-minerals
- Vitamins - fat soluble and water soluble
- Fatty acids - omeg-6 and omega-3 series
Vitamins
Organic compounds of low concentration that are variably provided in foods
Nutrients must be provided in ________ and _______ relative to one another.
Nutrients must be provided in proper amounts and proper proportions relative to one another.
Nutrient disproportion is known as a _______.
Malnutrition
Amount and proportions of nutrients needed vary with physiological state and disease. List 4 physiological states.
- Growth
- Maintenance
- Gestation
- Lactation
Define optimal nutrition.
A concept of animal response to nutrient exposure. Nutrients are provided in amounts and proportions that optimize a physiological or economically important response.
Define deficiency in regards to a nutrient-animal response relationship graph.
When response variable increases with increasing nutrient concentration.This condition indicates diet has too little nutrient, and that diet is not meeting the animal’s requirement for the nutrient.
Define suboptimal in regards to a nutrient-animal response relationship graph.
The response variable increases with increasing nutrient amount but diminishing returns occurs with further increases in nutrient amount.
Define optimal in regards to a nutrient-animal response relationship graph.
The animal response does not change with increasing nutrient amount. This condition is usually desired.
Define “excess” in regards to a nutrient-animal response relationship graph.
The response decreases with increasing nutrient amount. More nutrient is not always better, a nutrient may become toxic. Excess of a nutrient may cause deficiency of another nutrient. Amount excess that toxicity varies among species.
Determining “optimal” nutrient concentration.
- For each nutrient there is more than one response variable that may be used to determine the optimal nutrient amount.
- Body reserves of nutrient will affect the response to dietary concentration (i.e. a deficiency may not be observed for a long time because of body reserves. An apparently optimal concentration found in a short-term trial may actually be inadequate over long-term.
Define nutrient requirement.
Nutrient requirement is the minimum dietary amount of a highly bioavailable nutrient that optimizes a response important to a physiological feature.
