unsaturated fat

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Related to Polyunsaturate: polyunsaturated fatty acids


1. the adipose tissue of the body.
2. a triglyceride (or triacylglycerol) that is an ester of fatty acids and glycerol. Each fat molecule contains one glycerol residue connected by ester linkages to three fatty acid residues, which may be the same or different. The fatty acids may have no double bonds in the carbon chain (saturated fatty acids), one double bond (monounsaturated), or two or more double bonds (polyunsaturated). Essential fatty acids cannot be synthesized by the body but must be obtained from the diet or from intravenous infusion of lipids.
Saturated and Unsaturated Fats. All of the common unsaturated fatty acids are liquid (oils) at room temperature. Through the process of hydrogenation, hydrogen can be incorporated into certain unsaturated fatty acids so that they are converted into solid fats for cooking purposes. Margarine is an example of the hydrogenation of unsaturated fatty acids into a solid substance.
brown fat a thermogenic type of adipose tissue containing a dark pigment, and arising during embryonic life in certain specific areas in many mammals, including humans (see illustration); it is prominent in the newborn. Called also brown adipose tissue.
Sites of brown fat in the neonate. From McKinney et al., 2000.
neutral fat fat (def. 2).
polyunsaturated fat a fat containing polyunsaturated fatty acids; see also fat.
saturated fat a fat containing saturated fatty acids; see also fat.
unsaturated fat a fat containing unsaturated fatty acids; see also fat.

un·sat·ur·at·ed fat·ty ac·id

a fatty acid, the carbon chain of which possesses one or more double or triple bonds (for example, oleic acid, with one double bond in the molecule, and linoleic acid, with two); called unsaturated because it is capable of absorbing additional hydrogen.

unsaturated fat

Any of various fats derived from plant and some animal sources, especially fish, that are liquid at room temperature. Increasing dietary intake of unsaturated fats while reducing intake of saturated fats can reduce LDL cholesterol in the bloodstream.

unsaturated fat

An alkyl-chain fatty acid with one or more double (ethylenic) bonds between carbons (called unsaturated as the chain is capable of absorbing more hydrogen). Unsaturated fats  (UFs) have lower melting points, and most are liquid at room temperature. UFs can be monounsaturated (i.e., have one double bond, such as oleic acid), which are widely distributed in nature, or polyunsaturated (i.e., has two or more double bonds, such as linolenic acid), which are found in safflower and corn oils.

un·sat·ur·at·ed fat

(ŭn-sach'ŭr-āt-ĕd fat)
Fat containing a high proportion of unsaturated fatty acids, i.e., fatty acids with double or triple bonds between carbon atoms. May have a healthy effect on the heart when used in moderation by lowering cholesterol levels.

unsaturated fat

References in periodicals archive ?
However, this variation was less useful as mean polyunsaturate content was low.
N87-2122-4 (85 g [kg.sup.-1] total saturates and 435 g [kg.sup.-1] total polyunsaturates) was used as a tester in generating populations from crosses to the selected PI: N87-2122-4 X PI 342434 (Pop I); N87-2122-4 X PI 424031 (Pop II); and N87-2122-4 X PI 468910 (Pop III).
A mix of palm and rapeseed oil, with a blend of mono- and polyunsaturates, suitable for frying or salads.
When eaten cold - as in margarines or spreads high in polyunsaturates - there was less danger, he said.
Then, to pinpoint any effects the polyunsaturates might have on HDL cholesterol, Iacono and Dougherty lowered levels of polys to 3.8 percent for part of the study.
Researchers say a certain amount of the essential fatty acid in polyunsaturates is necessary for the body's system.
He notes that animal experiments have indicated some possible negative side-effects of polyunsaturates, including the development of cancer, the suppression of the immune system, and drastic changes in the cell membranes.
That monounsaturates might inhibit some cancers and polyunsaturates spur them has long been evident from studies by Leonard A.
When omega-3 makes up only 12 percent of polyunsaturates in the diet, production of prostaglandin E ([PGE.sub.2]), a "local hormone," is high, limiting bone growth, Watkins says.
Because white blood cells rich in omega-3 fatty acids tend to produce fewer of these compounds, Caughey's team tailored the diets of 28 men and women to derive most of their fat from either flax oil, rich in omega-3s, or sunflower oil, high in other polyunsaturates. After 4 weeks, concentrations of alpha-linolenic acid and eicosopentenoic acid-two types of omega 3s-in the blood of people eating sunflower oil remained comparable to amounts when the study began.
While holding the saturated- and monounsaturated-fat content constant, the researchers varied the type of polyunsaturates in the diet.
Furthermore, the polyunsaturates found in both fish and vegetable oils may lower the risk of heart disease independent of their effect on blood cholesterol.