Could the Quality of Dietary Fat, and Not Just Its Quantity, Be Related to Risk of Obesity?

Abstract

This review focuses on the possible association between types of fatty acids and weight change. It examines the biological plausibility underlining these associations and the evidence obtained to date from clinical trials and epidemiological studies. Animal studies have shown that dietary short-and medium-chain fatty acids compared to long-chain fatty acids appear to promote weight loss. Similarly, monounsaturated fatty acids (MUFAs) appear to favor weight loss compared to saturated fatty acids (SFAs) in human studies. The structure of fatty acids seems to affect their degree of oxidation and deposition. Although results are conflicting, human studies follow the general trend reported in animal studies. These trials suggest that some fatty acids are prone to oxidation and some others lead to fat storage when comparing isocaloric diets. For instance, n-3 polyunsaturated fatty acids (PUFAs), eicosapentaenoic and docosahexaenoic acids are preferentially oxidizied to other PUFA but results remain inconsistent. Epidemiological studies concerning this issue reported that total dietary fat, which includes MUFA, PUFA, and SFA could increase the risk of obesity, but results are few and conflicting. The rising biological plausibility linking dietary fat quality and risk of obesity, together with the rather recent addition of fatty acids content in food composition tables, support the need for major epidemiological studies in that area.Obesity (2008) 16, 7-15.

Regular intake of high-oleic peanuts improves fat oxidation and body composition in overweight/obese men pursuing a energy-restricted diet

“…Further, the HOP group had higher late postprandial fat oxidation at the initial test session than the CVP group. Differential oxidation of fatty acids varying in saturation have been reported (1,28) with higher rates noted for monounsaturated fatty acids (28). Consistent with this, the present trial noted that fat oxidation was augmented by consumption of high oleic acid peanuts compared to the conventional variety.…”

Unravelling the role of fatty acid metabolism in cancer through the FOXO3-FOXM1 axis

“…Furthermore, unsaturated FAs have higher oxidation rates than does long-chain SFAs and the length of the carbon chain of SFAs is inversely correlated with the oxidation rate (Moussavi et al, 2008;McDonald et al, 1980). Indeed, b-oxidation is higher with an increase in polyunsaturated/saturated ratio intake and this ratio affects the utilization of FAs in the diet (Moussavi et al, 2008).…”

“…It was demonstrated that polyunsaturated fatty acids (PUFA), but not monounsaturated fatty acids (MUFA) or saturated fatty acid (SFA) suppress the expression of genes involved in lipogenic transcription and are better activators of PPAR-a,g (Moussavi et al, 2008). Furthermore, unsaturated FAs have higher oxidation rates than does long-chain SFAs and the length of the carbon chain of SFAs is inversely correlated with the oxidation rate (Moussavi et al, 2008;McDonald et al, 1980). Indeed, b-oxidation is higher with an increase in polyunsaturated/saturated ratio intake and this ratio affects the utilization of FAs in the diet (Moussavi et al, 2008).…”

“…The diversity in FA structure (chain length, degree of unsaturation and position and stereoisomeric configuration of the double bonds) affect their metabolic fate (DeLany et al, 2000;Moussavi et al, 2008), different types of FAs presents b-oxidation and deposition rate differences (Moussavi et al, 2008). It was demonstrated that polyunsaturated fatty acids (PUFA), but not monounsaturated fatty acids (MUFA) or saturated fatty acid (SFA) suppress the expression of genes involved in lipogenic transcription and are better activators of PPAR-a,g (Moussavi et al, 2008). Furthermore, unsaturated FAs have higher oxidation rates than does long-chain SFAs and the length of the carbon chain of SFAs is inversely correlated with the oxidation rate (Moussavi et al, 2008;McDonald et al, 1980).…”

Trans fatty acids and weight gain

“…However, a recent review suggested that it may be not so much the amount of fat as the type of fat that should be considered. 10 Trans fatty acids (TFAs) are monounsaturated fatty acids (MUFAs) or polyunsaturated fatty acids (PUFAs) that contain at least one double bond in the trans configuration, rather than the usual cis configuration found in most lipids. This configuration may occur either as a result of microbial fermentation in the rumen (leading to the presence of TFA in dairy products or the meat of ruminants) or through the process of hydrogenation (giving rise to TFAs in spreadable fats that are commonly used in the baking industry).…”