Article

N-6 Fatty acids and cardiovascular health: A review of the evidence for dietary intake recommendations

Nutritional Epidemiology Research Unit, UMR INSERM U557, INRA U1125, CNAM, UP13, CRNH-IdF, Faculté SMBH, 74 rue Marcel Cachin, 93017 Bobigny, France.
The British journal of nutrition (Impact Factor: 3.45). 09/2010; 104(6):788-96. DOI: 10.1017/S0007114510002096
Source: PubMed

ABSTRACT

n-6 PUFA are well known for their critical role in many physiological functions and seem to reduce risks of CHD. However, some argue that excessive consumption of n-6 PUFA may lead to adverse effects on health and therefore recommend reducing dietary n-6 PUFA intake or fixing an upper limit. In this context, the present work aimed to review evidence on the link between n-6 PUFA and risks of CVD. Epidemiological studies show that n-6 PUFA dietary intake significantly lowers blood LDL-cholesterol levels. In addition, n-6 PUFA intake does not increase several CVD risk factors such as blood pressure, inflammatory markers, haemostatic parameters and obesity. Data from prospective cohort and interventional studies converge towards a specific protective role of dietary n-6 PUFA intake, in particular linoleic acid, against CVD. n-6 PUFA benefits are even increased when SFA intake is also reduced. In regards to studies examined in this narrative review, recommendation for n-6 PUFA intake above 5 %, and ideally about 10 %, of total energy appears justified.

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    • "It is also argued that higher dietary intake of n-6 PUFA may lead to a competition between n-6 and n-3 metabolism resulting in a reduced production of anti-inflammatory molecules from n-3 PUFA.[47] However, in human subjects, higher intakes of n-6 fatty acids do not appear to be associated with elevated levels of inflammatory markers and there are no data from human studies that support a detrimental effect of dietary n-6 fatty acids on coronary heart disease.[4849] The present results are in contrast to customary assumption that high intake of n-6 fatty acids antagonizes the anti-inflammatory effects of n-3 fatty acids. "
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