Fat Ratio in Modern Diet and It’s Complications
Today, in Western societies the ratio of Omega 6: Omega 3 consumption is about 16:1 due to the high intake of vegetable oils-soybean, corn oil, sunflower, safflower, and linseed oil, which are actually very high in Omega 6 Fatty Acid (Simopoulos & Robinson, 1999). Linoleic acid (LA) is found in high amounts in grains but, grains like flaxseed, chia, perilla, rapeseed, and walnuts are rich in Alpha-Linolenic Acid (ALA). The green leaves of plants, particularly wild plants are higher in ALA than LA. Omega-3 fatty acids modulate prostaglandin metabolism and decrease triglycerides. And, high doses consumption lowers cholesterol and have anti-thrombotic and anti-inflammatory properties. These studies have been extensively reviewed (Burr et. al.,1988).
DHA (Docosahexaenoic Acid) is found in high amounts in the membranes of brain and retina and is critical for proper neurogenesis, neurotransmitter metabolism, neuroprotection and vision. The consumption of high amounts of DHA has been associated with multiple health benefits including brain and retinal development, aging, memory formation, synaptic membrane function, photoreceptor biogenesis and function, and neuroprotection. DHA is also very essential for prenatal brain development (Niemoller et.al., 2008).
There is evidence that changes in fatty acid composition are one of the major cause for pathophysiology of major depression (Hibbeln & Salem, 1995). Changes in serotonin or 5-hydroxytryptamine (5-HT) receptor number and function caused by changes in PUFA(Poly Unsaturated Fatty Acid) provides the theoretical rationale explaining that the fatty acids acts as one of the cause for ignition of Depression as well. The increased Arachidonic acid (C20 : 4ω6) to Eicosapentaenoic acid (C20/5ω3) ratio or in simple, the imbalance in the omega-6 and omega-3 PUFA ratio in major depression may be related to the increased production of proinflammatory cytokines and eicosanoids (Hibbelnet et. al. , 1998).
There are a number of studies evaluating the therapeutic effect of EPA and DHA in major depression. Stoll and colleagues(1999)have shown that EPA and DHA prolong remission, that is, reduce the risk of relapse in patients with bipolar disorder. Conklinet et. al.,(2010) studied depressive symptoms, omega-6:omega-3 fatty acid ratio and inflammation in older adults. As the dietary ratio of omega-6:omega-3 increased, the depressive symptoms, proinflammatory cytokines (TNF-α, IL-6, and IL-6) soluble receptor also increased. The authors concluded that diets with a high omega-6:omega-3 ratio increases the risk for both depression and inflammatory diseases(Simopoulos, 2011).
