Polyunsaturated fatty acid balance

Canola Oil Canola oil is obtained from low erucic acid, low glucosinolate rapeseed. The unique polyunsaturated fatty acid and low saturated composition of canola oil differentiates it from other oils. It has a higher oleic acid (18 1) content (55%) and lower linoleic acid (18 2) content (26%) than most other vegetable oils, but it contains 8-12% of linolenic acid (18 3) (58). Canola oil is most widely used in Canada and is considered a nutritionally balanced oil because of its favorable ratio of near 2 1 for linoleic to linolenic acid content. Unlike most other edible oils, the major breakdown products of canola oil are the cis, trans- and tram, trans-2,4-heptadienals with an odor character generally described as oily, fatty, and putty. Stored canola oil shows a sharp increase in the content of its degradation products, which are well above their odor detection thresholds. The aroma is dominated by cis, tram-, tram, frani-2,4-heptadienals, hexanal, nonanal, and the cis, trans- and... 

Delion S, Chalon S, Guilloteau D, Lejeune B, Besnard JC, Durand G. Age-related changes in phospholipid fatty acid composition and monoaminergic neurotransmission in the hippocampus of rats fed a balanced or an n-3 polyunsaturated fatty acid deficient diet. J Lipid Res 1997 38 680-689. 

In the current model, fat contributed 24% of the total energy derived from all wild plant food (n = 768), whereas carbohydrate (62% energy) and protein (14%) comprised the balance of plant food energy. The mean fatty acid breakdown for 64 cultivated equivalent category plant foods was 22.4% saturated fatty acids, 28.6% monounsaturated fatty acids, and 49% polyunsaturated fatty acids. Accordingly, in our model, 5.4% of plant food energy was derived from saturated fat. 

The right balance of n-6 and n-3 polyunsaturated fatty acids (PUFA) is important for good health. The n-3 PUFA such as eicosapentaenoic acid PA) and docosahexaenoic acid (DHA) are mainly found in fish oils. Marine plants can convert a-linolenic acid (ALA) into EPA and DHA, which find their way through the food chain to fish tissues. Another source of n-3 PUFA is the ALA that is found mainly in flaxseed, canola, and soybean oils. Unlike plants, mammals cannot convert oleic acid into linoleic acid, linoleic acid into ALA, or convert n-6 PUFA to n-3 PUFA. Linoleic acid and n-3 PUFA are therefore known as essential fatty acids (1). 

The dietary intake of polyunsaturated fats and minerals is clearly not a simple problenL Dietary recommendations for polyunsaturated fats and especially the highly oxidizable n-3 polyunsaturated lipids must consider their susceptibility to oxidation as a significant risk factor. When the interrelationships between the metabolic effects of different polyunsaturated fatty acids are better understood, an appropriate target may be to achieve a balanced eicosanoid metabolism. It would seem imprudent to make dietary reconunendations to the public before the mechanisms of polyunsaturated hpid nutrition, in vivo activity of antioxidants, and in vivo lipid peroxidation are better understood. 

As mentioned earlier, saturated fatty acids (SFA) of foods are regarded as the cause of a high-risk pattern of blood lipoproteins octadecanoic (stearic, Cig) acid and tetradecanoic (myristic, C14) acid and also all trans acids are considered to be the most damaging. With increasing consumption of SFA, blood levels of cholesterol and LDL are raised. Conversely, the polyunsaturated fatty acids (PUFA) are judged to be beneficial, although the various families of PUFA differ in their effects the n-6 PUFA (which occur mainly in plant lipids) reduce the blood concentration of LDL, and the n-3 PUFA (from fish lipids) reduce VLDL. It is considered desirable to have a balance in the diet of n-6 to n-3 PUFA the recommended maximum ratio is 4 1. In between the SFA and PUFA are the monounsaturated fatty acids (MUFA), such as octadecenoic (oleic, 18 1) acid, which are regarded as neutral or possibly beneficial to blood lipoproteins. 

Prebiotics, polyunsaturated fatty acids (PUFAs) and phytochemicals are the most well characterized dietary bioactive compounds. The beneficial effects of prebiotics mainly relay on their influence on the gut microbiota composition and their ability to generate fermentation products (short-chain fatty acids) with diverse biological roles (Laparra and Sanz 2010). PUFAs include the co3 and co6 fatty acids, whose balance may influence diverse aspects of immunity and metabolism. 

In section 3.4 we described the biosynthesis of eicosanoids from polyunsaturated fatty acids of the n-3 and n-6 families and indicated in section 3.4.8 that the balance of eicosanoids produced was important in, for example, maintaining normal vascular function. Several studies have demonstrated that altering the amounts and types of n-6 and n-3 fatty acids in the diet can influence the spectrum of eicosanoids produced. For example, substitution of fish oils in which n-3 polyunsaturated fatty acids predominate for diets in which linoleic acid (n-6) is the main polyunsaturated fatty acid (as typified by the UK diet) results in changes in plasma and platelet fatty acid profiles from arachidonic to eicoasapentaenoic acid as the predominant polyunsaturated fatty acid and a reduction in the formation by platelets of thromboxane A2, an eicosanoid that stimulates their aggregation (Table 5.7). 

But in spite of the potential usefulness of q>-3 fatty acids in the treatment of occlusive vascular disease, it has to be pointed out that a balanced view of any new form of therapy is absolutely essential. There are too many questions remaining, and consequently we must not be overenthusiastic. Animal experiments are only rough indications of human conditions, and the metabolism and transport mechanisms for polyunsaturated fatty acids may differ substantially from those in humans. 

Optimum balance of the three principal fatty acids polyunsaturates, mono-unsaturates, and saturates. The patented oil blend enhances the good to bad cholesterol ratio when fat intake is balanced in the diet with total fat limited to 30% of calories and dietary cholesterol to under 300 mg per day. 

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