nutrition-fats Flashcards
Mention its RDA.
Infant= 31-37 g/day
Adult men= 54-82
Adult women= 46-70
Pregnant women, 3rd trimester =57-85
Essential fatty acids.
* Define.
polyunsaturated fatty acids (PUFA) which the body cannot synthesise and, therefore, must be consumed in the diet
Essential fatty acids.
- List the examples.
- Linoleic acid - omega 6
- Linolenic acid- omega 3
look at mindmap
MCQ
*Formation of healthy cell membranes.
*Proper growth and reproduction of the organisms.
*Prevent fat accumulation in the liver.
*Participate in the transport and utilisation of cholesterol.
* Required for the synthesis of hormone-like substances called eicosanoids.
Essential fatty acids.
* Explain the deficiency symptoms.
- EFA deficiency is caused primarily by fat malabsorption.
- Most often occur in infants fed diets deficient in EFA.
- Symptoms:
✓Scaly dermatitis→as a result of the depletion of skin ceramides with long chain FA.
✓Decreased growth in children and infant.
✓Poor wound healing and hair loss is also observed.
Eicosanoids.
* Outline the steps of synthesis.
Two main pathways:
1. The cyclooxygenase pathway: prostaglandins
and thromboxanes
2. The lipoxygenase pathway: leukotrienes
look at notes
. Eicosanoids.
* List the general functions.
✓Produced in very small amounts in almost all tissues, act locally, and have an extremely short half-life.
✓They serve as mediators of the inflammatory response.
* Examples of eicosanoids: prostaglandins (PG), thromboxanes (TX), and leukotrienes (LT).
- Describe the effect of anti-inflammatory drugs (steroidal and non-steroidal).
- Steroidal
➢Corticosteroids. Exp: Cortisol (a steroidal anti-inflammatory agent)
➢Actions: Inhibits phospholipase A2 activity, therefore, arachidonic acid is not released from membrane phospholipids and block the synthesis of eicosanoids. - Nonsteroidal
➢Nonsteroidal anti-inflammatory drugs (NSAIDs). Exp: aspirin, ibuprofen, indomethacin.
➢Actions: Inhibits both cyclooxygenase 1 and 2 activity, and thus, prevent the synthesis of prostaglandins and thromboxanes.
Define saturated and unsaturated fatty acids giving examples with their sources.
Saturated FA:
-fatty acids whose hydrocarbon chains do not contain any double bonds
Exp: stearic acids, palmitic acid, myristic acid and lauric acid.
sources: dairy and meat products and some vegetable oils, such as coconut and palm oils.
1) Monounsaturated FA (MUFA)
* TAG containing primarily fatty acids with one double bond.
* Exp of MUFA is oleic acid which can be obtained from plant-based
oils (olive oils, pecan oils).
2) Polyunsaturated FA
* TAG containing primarily fatty acids with more than one double bond.
* Exp of PUFA: Omega-6 fatty acids and Omega-3 fatty acids.
Describe the role of dietary fats in coronary heart disease (cholesterol, TAG, saturated, monounsaturated fatty acids, polyunsaturated fatty acids (n-3, n-6), trans fats and alcohol).
look at table
Dietary cholesterol
* The effect is less important than other types of fatty acids.
*experts recommend ~300 mg/day. However, having an upper limit cause increased incidence of CHD.
Alcohol
* Moderate consumption of alcohol; no effect on CHD.
* High alcohol intake, increased risk of CHD.
Summarize the advantages of Mediterranean diet.
-diet rich in MUFA and PUFA and low in saturated fat.
* contains seasonally fresh food, with an abundance of plant material, low amounts of red meat, and olive oil
1) Promotes heart health and increased life span.
✓Healthy fats diet, decreased plasma total cholesterol, LDL-C, and TAG, and increased HDL-C when compared with a typical Western diet higher in saturated fats.
2) Promotes healthy weight and reduce risk of developing type 2 diabetes
✓High fibres content in the diet helps control the blood glucose level.
3) Reduce cancer risk and good for memory
✓contains naturally high levels of antioxidants from a variety of colorful plant foods.
✓Antioxidants help stop or slow oxidative damage and reduce inflammation throughout the body—associated with a reduced risk of cancer and neurodegenerative diseases.
