With many contributors to the steadily rising rates of obesity and type-2 diabetes researchers are arguing that one of these could be due to the incredibly unbalanced consumption of omega-6 versus omega-3 fatty acids.
The Western diet consists primarily of "pro-inflammatory and thrombogenic" omega-6 at the expense of omega-3, a protective fatty acid. The ration of omega-6:3 used to be at about 1:1 and has skyrocketed to 16:1. The drastic proportion of omega-6 to omega-3 is the most dramatic change that has occur to the Western diet in the past 100 years. The high consumption of refined seed oils and reduction in omega-3 could be a leading cause for the increase in obesity.
The advances in modern agriculture are one of the reasons we see this trend. Grain-fed animal byproducts are higher in omega-6, whereas grass-fed animal products such as milk are richer in omega-3. This is not only contributing to an increase in obesity rates, but other chronic diseases as well.
Omega-3 fats provide fat burning signals in the body, conversely omega-6, particularly from vegetable oils, provide fat storing signals. With our bodies ratio of omega-6:3 ratio being so strongly in favor of omega-6 we are sending signals to not only store fat, but also creating inflammatory fat.
Omega-6 is specifically impacting obesity and type 2 diabetes, alone with increasing leptin and insulin resistance, waist circumference, oxidation, triglycerides, inflammation, adipose cells, and white adipose tissue. The low intake of omega-3 is leading to increased appetites, lipogenesis and obesity.
A recent NIH Women's Health Initiative study reported that high concentrations of omega-6 in blood was positively associated with increased weight gain in young women.
A certain genetic predisposition disproportionately increases omega-6 levels in the blood when linoleic acid (ex. vegetable oil) is consumed. With the genetic feature present there is a significantly greater risk for obesity and type 2 diabetes.
There needs to be a lower intake of industrial seed oils, and high emphasis on the intake of nuts, seeds and oceanic seafood, increasing the intake of ALA and EPA/DHA, not only decreasing risk of a number of chronic diseases but, weight as well.
Although there are benefits in the consumption of omega-6 it is important to not forget about omega-3 and the ratio in which the two are being consumed.
Omega-3 has benefits beyond weight loss and diabetes, but cognitive functioning and arthritis as well, and can even be crucial in fighting lung infection.