chap4 lipid nutrition in health and disease
TRANSCRIPT
Any of a group of substances Any of a group of substances that in general are soluble in that in general are soluble in organic solvents, but are not organic solvents, but are not soluble in water.soluble in water.
The term fats and lipids used interchangeably
Source of energy (9 kcal/g)Energy reserve: any excess energy from
carbohydrate, protein and lipids are stored in adipose tissues
Provide insulation to the body from coldMechanical insulation: protects vital organs
Supply Essential Fatty Acids (EFA)Linoleic acid and linolenic acid
Helps in the formation of cell membranes Phospholipids
Help carry fat soluble vitaminsFlavor and tasteThe satiety value
Fullness; fats are digested slower
1. Fatty acids
2. Neutral fats and oils
3. Waxes
4. Phospholipid
5. Sterols
6. Fat soluble vitamins
Types of Lipids
The basic structural unit of lipidCommon in food fats and oilsHas 3 classes according to their degree of
saturationFully saturatedMonounsaturatedPolyunsaturated
Also vary in chain according to the number of atomsShort chains fatty acids 2 to 4 carbon atomsMedium chains have 6 to 10 carbon atomsLong chains have 12 to 26 carbon atoms
Linoleic and arachidonic acid are essential fatty acids
It maintain the function and integrity of cell membranes
Are used to esterify cholesterol in plasmaRequired for metabolism of cholesterol and lipidsLinoleic acid derivatives have been shown to be
precursors for a group hormone like compounds called prostaglandins
Linoleic acid deficiency: signs and symptoms of scaly skin, sparse hair growth, poor wound healing and thrombocytopenia (decrease in blood platelets)
Are a class of lipids and are a major component of all cell membranes as they can form lipid bilayers
Divided into 3 groupsPhospatides – form part of the cell walls and
mitochondriaLecithin –egg yolks and meat, used as emulsifying agent
in mayonnaise and salad dressingsCephalin – egg yolks and in brain, present in
thromboplastin which is needed in the blood clotting process
Sphingomyelins – a component of a fatlike sheath substance, tghe insulation around nerve fibers
Plasmalogens – related to the specialized function in platelets in blood coagulation
Is a waxy, fat-like substance that is made in the body by the liver
It forms part of every cell in the body and serves many vital functions:Maintain healthy cell wallsMakes hormones (the body’s chemical
messengers)Make vitamin DMake bile acids, which aid in fat digestion
Excess cholesterol circulates in blood stream can clog blood vessels and increase the risk for heart disease and stroke
Low-Density Lipoprotein (LDL) – a bad type of cholesterol that is most likely to clog blood vessels , increasing your risk for heart disease
High-Density Lipoprotein (HDL) – good type of cholesterol, helps clear the LDL cholesterol out of the blood and reduces the risk of heart disease