Understanding Nutrition

Nutrients are chemical substances obtained from food and used in the body to provide energy, structural materials, and regulating agents to support growth, maintenance, and repair of the body's tissues.  Nutrients may also reduce the risk of some diseases.

• Carbohydrates
• Lipids (fats)
• Proteins
• Vitamins
• Minerals
• Water

Essential nutrients are nutrients that a person MUST obtain from food because the body can NOT make them for itself in sufficient quantity to meet physiological needs.

*40 nutrients are currently know to be essential for human beings

• In the body 3 organic nutrients  can be used to provide energy:
• Carbohydrates
• Lipids/Fat
• Protein

The amount of energy a food provides depends on how much carbohydrate, fat, and protein it contains.

• 1 gram of carbs   = 4 kcalories
• 1 gram of protein = 4 kcalories
• 1 gram of fats     = 9 kcalories

It is a measure of the energy a food provides relative to the amount of food (kcalories per gram).

Alcohol.  

It does NOT sustain life.  It interferes with the growth, maintenance, and repair of the body.

* 7 kcalories p/gram

Water

Metabolism

Moderation and variety

45-65 %

Inorganic elements.  Some minerals are essential nutrients required in small amounts by the body for health.

not containing carbon or pertaining to living things.

In agriculture: Alive

• Minerals
• Water

• Carbohydrates
• Lipids (fats)
• Protein
• Vitamins

It is the study of the nutrients and other substances in foods and the body's handling of them.

DRI's are a set of nutrient intake values for healthy people in the US & Canada.

These values are used for planning and assessing diets.

The daily intake of a specific nutrient estimated to meet the requirement in 50% of healthy people in an age- and gender-specific group. The EAR is used to calculate the recommended dietary allowance.

The Recommended Dietary Allowances (RDAs) are quantities of nutrients in the diet that are required to maintain good health in people. RDAs are established by the Food and Nutrition Board of the National Academy of Sciences, and may be revised every few years. A separate RDA value exists for each nutrient. The RDA values refer to the amount of nutrient expected to maintain good health in people. The actual amounts of each nutrient required to maintain good health in specific individuals differ from person to person.

A recommended intake value based on observed or experimentally determined approximations or estimates of nutrient intake by a group (or groups) of healthy people, which are assumed to be adequate-used when a recommended daily amount cannot be determined.

The maximum level of continuing daily nutrient intake that is likely to pose no risk to the health of most of those in the age group for which it has been established.

A range of intakes for a particular energy source that is associated with reduced risk of chronic disease while providing adequate intakes of essential nutrients. Expressed as a percentage of totalenergy intake, AMDRs have been established for protein, carbohydrate, fat, and linoleic (n-6) and alpha-linolenic (n-3) polyunsaturated fatty acids.

• Carbohydrates = 45-65% kcalories
• Lipids/Fats      = 20-35% kcalories
• Protein           = 10-35% kcalories

• 1. Reviewing historical info on diet & health 
• 2. Lab tests
• 3. Anthropometric Measures
• 4. Physical Exams

Malnutrition

*Mal = bad

Undernutrition

Overnutrition

Overt

*Ouvrir= to open

A nutrient deficiency caused by inadequate dietary intake of a nutrient

A nutrient deficiency caused by something other than an inadequate intake such as a disease condition or drug interaction that reduces absorption, accelerates use, hastens excretion, or destroys the nutrient

A deficiency in the early stages, before the outward signs have appeared.

Hidden, as if under covers.

* couvrir=to cover

Diseases characterized by a slow progression and long duration.

A condition or behavior associated with an elevated frequency of a disease but not proved to be causal.

Servings Per Day:

• 6-11: Grains
• 3-5:  Vegetables
• 2-4:  Fruits
• 2-3:  Milk/Milk Alternatives
• 2-3:  Meat/Meat Alternatives

*Use Oils sparsely

• Weight
• Nutrition facts based on standard serving sizes
• Daily Values based on a 2000 kcalorie diet

high or low

relationship between a nutrient and a disease

reflect relationships between a nutrient and its function in the body

• Adequacy
• Balance
• kCalorie (energy) control
• Nutrient density
• Moderation
• Variety

Providing all the essential nutrients, fiber, and energy in amounts sufficient to maintain health.

Providing foods in proportion to one another and in proportion to the body's needs.

Management of food energy intake

Providing enough but not too much of a substance.

Eating a wide selection of foods within and among the major food groups

The process by which food is broken down into absorbable units.

* Digestion = take apart

• 1. Ingestion of food through Mouth
• 2. Pharynx directs food to esophagus
• 3. Salivary glands secrete saliva
• 4. Epiglottis protects airways during swallowing 
• 5. Trachea allows air to pass to lungs
• 6. Esophagus passes food from mouth to the stomach
• 7. Esophageal sphincters regulate/prevent backflow
• 8. Food passes through diaphragm
• 9. Reaches the stomach, adds acid, enzymes and grinds food to liquid mass
• 10. Pyloric sphincter allow passage to small intestine, prevents backflow
• 11. Liver manufactures bile salts
• 12. Gallbladder stores bile until needed
• 13. Bile duct conducts bile from gallbladder to the small intestine
• 14. Appendix stores lymph cells
• 15. Small intestine secretes enzymes that digest all energy-yielding nutrients, cells of wall absorb nutrients into blood and lymph
• 16. LLeocecal valve allows passage from small intestine to large, prevents backflow
• 17. Pancreas manufactures enzymes to digest all energy-yielding nutrients and releases bicarbonate to neutralize acid chyme that enters the small intestine
• 18. Pancreatic duct conducts juice from pancreas to small intestine
• 19. Large intestine (colon) reabsorbs water & minerals, passes waster to rectum
• 20. Rectum stores waste prior to elimination
• 21. Anus holds rectum closed, open to allow elimination
• 22. Elimination happens

The digestive tract.  The principal organs are the stomach and intestines

Wavelike muscular contractions of the GI tract that push its contents along

• *Peri=around
• *Stellein=wrap

Protein found in digestive juices that act on food substances, causing them to break down into simpler compounds.

The lower portion of intestine that competes the digestive process.  Its segments are:

• 1. the ascending colon
• 2. transverse colon
• 3. the descending colon
• 4. sigmoid colon

The uptake of nutrients by the cells of the small intestine for transport into either the blood or the lymph.

Liver

Gallbladder

The semiliquid mass of partly digested food expelled by the stomach into the duodenum

emulsify fats

liver

• 1. Gastrin
• 2. Secretin
• 3. Cholecystokinin (CCK)

Hormone secreted by cells in the stomach wall.

Target organ: the glands of the stomach

Response: secretion of gastric acid

Hormone produced by cells in the duodenum wall.

Target organ: the pancreas

Response: secretion of bicarbonate-rich pancreatic juice

Hormone produced by cells of the intestinal wall.  

Target organ: the gallbladder

Response: release of bile & slowing of GI motility

Top portion of the small instestine

Compounds composed of carbon, oxygen, and hydrogen (CH2O) arranged as MONOsaccharides or multiples of monosaccharides

• * carbo= carbon
• *Hydrate = with water