Saturated fatty acids dietary

Merkel M, Velez-Carrasco W, Hudgins LC, Breslow JL. Compared with saturated fatty acids, dietary monounsaturated fatty acids and carbohydrates increase atherosclerosis and VLDL cholesterol levels in LDL receptor-deficient, but... 

The details of population dietary guidelines for the quality and quantity of fat intake differ between countries. However, in consideration of prevention of CHD, dietary guidelines generally reflect advice to reduce average total fat intakes to 30-35% dietary energy and to lower saturated fat intakes to approximately 10% of dietary energy. Though the effect of trans fatty acids on the plasma LDL/ HDL ratio is less favorable than that of saturated fatty acids, dietary advice needs to reflect the relative intakes of these two types of fatty acids. Since... 

Dairy products (see Milk and milkproducts) have been staple items of the diet for many centuries, and have long been the target for imitation. The development of nutritional guidelines emphasizing the need to reduce total dietary fat, dietary cholesterol [57-88-5] C2yH4 0, and saturated fatty acids (see Fats and fatty oils Fat substitutes), has increased the interest in imitation dairy foods. However, with the exception of butter and cream the market penetration of dairy substitutes has been limited. 

Excessive dietary intake of cholesterol and saturated fatty acids leads to decreased hepatic clearance of LDL and deposition of LDL and oxidized LDL in peripheral tissues. 

Interest in the health effects of anthocyanins was piqued by the French paradox in which the mortality from cardiovascular disease was lower than that predicted from the intake of dietary saturated fatty acids. The beneficial effects were greater in association with alcohol taken in the form of wine suggesting that there may be a protective effect of other components of wine. Needless to say the wine industry was pleased with this research. 

Dietary saturated fatty acids have undesirable effects on plasma lipids... 

The effects of dietary lipids on human health are complex. However, in general dietary terms, monounsaturated fatty acids are considered to be more healthful than saturated fatty acids. A lot of people, concerned about their health, have decreased their dietary intake of butter in favor of olive oil or vegetable oils. 

Meat products provide approximately 36% of the energy and many of the required nutrients in the diet They also contribute more than 50% of the total fat, 75% of the saturated fatty acids and essentially all of the cholesterol. Consumers have been advised to reduce their dietary fat and cholesterol levels for health reasons, and the utilization of red meats has suffered greatly in the past few years. Consumption of red meat products world-wide has been reduced considerably compared to a high consiunption of 3.1 million tons per year in 1986-1988 (i). 

One of the building blocks of dietary fats are fatty acid molecules, as shown to the right. Every fatty acid molecule consists of a long chain of nonpolar carbon atoms attached to a polar carbon and oxygen unit known as a carboxylic acid. As discussed in Chapter 13, there are two types of fats—those made from fatty acids with no double bonds, and those made from fatty acids with one or more double bonds. Fatty acids with no double bonds are called saturated fatty acids, while those with one or more double bonds are called 1msaturated fatty acids. 

The usual diet of ruminants consists of fresh and preserved herbage and cereals. As a result of microbial activity in the rumen, esterified dietary fatty acids are hydrolyzed, short chain fatty acids are produced by fermentation of cellulose and other polysaccharides, unsaturated fatty acids are hydrogenated and/or converted to geometric (trans) and positional isomers, and microbial lipids are synthesized. These activities account in part for the enormous diversity of fatty acids in milk and the unique features short-chain and a high proportion of long chain saturated fatty acids. (Patton and Jensen, 1976 Christie, 1979B). 

Dairy products provide a source of dietary saturated fatty acids. Generally, saturated fatty acids have been reported in the literature to increase LDL-cholesterol (Katan et al., 1994), a risk factor for CHD (Lamarche... 

In the Nurses Health Study (Hu et ah, 1997), the dietary intake of short- and medium-chained saturated fatty acids (4 0-10 0) was not significantly associated with CHD (but other saturated fatty acids were). In an intervention study a higher intake of medium-chained triglycerides was found to significantly decrease total adipose tissue, subcutaneous adipose tissue, and upper-body adipose tissue stores in men compared to longer chained triglyceride consumption (St-Onge, 2005). 

Two saturated fatty acids, pentadecanoic acid (15 0) and heptadeca-noic acid (17 0), in adipose tissue (Baylin et al., 2002) and serum lipids (Smedman et al., 1999 Sun et al., 2007a Wolk et al., 1998) have been proposed and validated as biomarkers of dietary ruminant fat intake, that is, mainly from milk fat and to lesser extent from ruminant meat. The human body is unable to synthesize fatty acids with an uneven number of carbon atoms, whereas ruminal microbes of cows have this ability (Wu and Palmquist, 1991). To measure the content of 15 0 and/or 17 0 in plasma lipids or adipose tissue is consequently a way to estimate the milk fat intake. It is known that the proportion of 15 0 and 17 0... 

Samuelson, G., Bratteby, L. E., Mohsen, R., and Vessby, B. (2001). Dietary fat intake in healthy adolescents Inverse relationships between the estimated intake of saturated fatty acids and serum cholesterol. Br. J. Nutr. 85,333-341. 

As indicated above, there are many possible oxidation products of the different polyenoic acids. It is probably naive to ascribe the effects of dietary intervention reported thus far to such metabolites. Carefully controlled clinical studies will be needed before these questions can be satisfactorily answered. However, subjects on diets containing highly saturated fatty acids clearly show increased platelet aggregation when compared with other study groups. Such diets (eg, in Finland and the USA) are associated with higher rates of myocardial infarction than are more polyunsaturated diets (eg, in Italy). 

Experimental 1 T, dietary fats, both quantity and quality, play important roles in the genesis of cancers of many organs (18,19). Earlier, we demonstrated that a high fat CD diet is a more efficient liver tumor promoter than the diet with a low fat content (5). The proportion of saturated and polyunsaturated fatty acids in a CD diet is an important determining factor for the severity of the diet-induced fatty liver (20,21). Saturated fatty acids containing 14 to 18 carbons in the diet appeared to increase the deposition of fat in the liver more so than unsaturated fatty acids (22). It became of considerable interest to determine whether and how changing the quality of fat in a CD diet modifies the promoting efficacy of the diet. 

Dietary supplementation studies with n-3 fatty acids alone have generally not been promising in atopic dermatitis. An initial double-blind study reported a subjective improvement on fish oil compared with the control OA, but no objective improvement on physician assessment.179 A further double-blind study using EPA with saturated fatty acids as the control, showed equal improvement with both supplements and the benefit was attributed to increased clinician guidance,180 while a multicenter study showed a similar improvement in clinical score in subjects taking fish oil or corn oil.181 The latter results might possibly reflect a beneficial effect of both EFA-containing oils, but more likely imply a placebo effect, and illustrate the problems posed both in selection of a suitable control and the interpretation of such studies. 

The total fat intake must be reduced to achieve weight reduction by diet therapy.70 Dietary recommendations also include a reduction in saturated fatty acids. Drug therapy must be started only after confirmation of lipid levels such as cholesterol, triglycerides, LDL, and HDL. Adequate trial must be initiated with modification of dietary therapy, only failing which drug therapy must be started. 

Jerusalem artichoke tubers contain little or no starch, virtually no fat, and have a relatively low calorific value. Of the small amount of fat present, trace amounts of monounsaturated and polyunsaturated fatty acids have been reported, but no saturated fatty acids (Whitney and Rolfes, 1999). The polyunsaturated fatty acids linoleic (18 2 cis, cis n-6) and a-linoleic acid (18 3 n-3) have been recorded as present at 24 mg and 36 mg-100 g 1 of raw tuber, respectively (Fineli, 2004). The tubers are a good source of dietary fiber, because of the presence of inulin. 

Ertas et al. (2005) investigated the potential effects of dietary supplementation by coriander seed (considered as a lipolytic and antioxidant compound) on carcass lipid composition of quails. Their aim was to reduce saturated fatty acid consumption and to increase essential fatty acids (particularly n3 unsaturated acids) in alimentation. Dietary supplementation by coriander seed affected the lipid composition of carcass greatly by decreasing saturated fatty acid (SFA) contents (palmitic and stearic acids) and by increasing monounsaturated and polyunsaturated fatty acid (MUFA and... 

CLA refers to a mixture of positional and geometric isomers of linoleic acid (cis-9, cis-12 octadecadienoic acid) with a conjugated double bond system. The structure of two CLA isomers is contrasted with linoleic and vaccenic acids in Figure 3.1. The presence of CLA isomers in ruminant fat is related to the biohydrogenation of polyunsaturated fatty acids (PUFAs) in the rumen. Ruminant fats are relatively more saturated than most plant oils and this is also a consequence of biohydrogenation of dietary PUFAs by rumen bacteria. Increases in saturated fatty acids are considered undesirable, but consumption of CLA has been shown to be associated with many health benefits, and food products derived from ruminants are the major dietary source of CLA for humans. The interest in health benefits of CLA has its genesis in the research by Pariza and associates who first demonstrated that... 

Hayes, K.C., Pronczuk, A., Lindsey, S., Diersen-Schade, D. 1991. Dietary saturated fatty acids differ in their impact on plasma cholestrol and lipoproteins in non-human primates. Amer. J. Clin. Nutr. 53, 491 498. 

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