Aragon on Fish Oil

Remember the fat free 80s?  Aragon does:
"No worries, though, these (muffins, cookies, candies, weight gain products) were virtually fat-free! What we were led to believe was that fat-free products equated to fat-free physiques. Unfortunately, that was far from the truth."

Then the fat shoe fell:

During the 1980’s national obesity rates started to drastically climb. Large behavioral trend studies such as the National Health and Nutrition Examination Study (NHANES II & III), the Behavioral Risk Factor Surveillance System (BRFSS), and the Calorie Control Council Report (CCCR) collectively showed a 31% increase in overweight prevalence from 1976-1991. What is the punch line? This increase in weight was accompanied by an 11% decrease in percentage of calories from fat (from 41.0% to 36.6%). The most recent report by the BRFSS shows a further decrease in fat intake to 33%, accompanied by an increase in obesity from 11.6% to 22.1%. This is a 90.5% increase in US obesity from 1990-2002[1]. It’s obvious that dietary fat is not the evil culprit in the expansion of the population’s waistline.

http://www.wannabebig.com/supplements/fish-oil-just-the-facts/

Good fats bad fats:

Stearic acid, an SFA abundant in meat & milk fat, has been consistently observed to actually reduce blood platelet aggregation [2]. This is a good thing. In contrast, trans fats (found in high concentrations in commercially baked goods as well as processed & fried foods) have been observed to negatively impact blood lipids by not only lowering HDL, but increasing LDL as well [3]. 

Ironically, experimental research exists on healthy humans showing the least fat was oxidized on the MUFA fat dietary treatment, and the most fat oxidized on a trans fat diet [4]. This result echoes what has been seen in rats as well. It appears that the tighter the control of the study, the less “superior” unsaturated fats turn out to be for any presumed effect on body composition compared to SFA. Throw in the fact that a reducing SFA intake and increasing the degree of unsaturation of fatty acids in the diet reduces testosterone levels [5], and then you have yet another wrinkle in the mix.

Omega 3s are not all the same:

Consumption of EPA and DHA has an appreciable number of positive health effects, including decreases in blood platelet aggregation, lowered blood pressure, enhancement of smooth muscle function, decreased inflammation, alleviation of dyslipidema, and treatment of mood disorders [6-9]. There is also emerging evidence pointing to the benefits of omega-3 fatty acids on bone health [10].

What's Normal?  Why don't we get a "normal" amount of omega 3/6?

Archaeological research postulates that humans were biologically designed to thrive on a diet whose ratio of omega-6 to omega-3 fatty acids was approximately 1:1, and unlikely greater than 4:1. Today, consumption of n-6 to n-3 fatty acids is estimated at roughly 25:1 [11]. This is due in part to a predominance of omega-6 oils available commercially in our food supply (corn oil, sunflower oil, safflower oil, refined packaged grain products & pastries) and a relative minority of omega-3 sources (fatty marine fish such as salmon, mackerel, herring, and flaxseed oil, walnuts, & small amounts in canola oil).

Industrial production of omega-6-rich animal feeds has also resulted in animal tissues (livestock, eggs, and cultured fish) rich in omega-6 and poor in omega-3 fatty acids. This disproportionately high intake of omega 6’s biases our physiology towards thrombosis, hyperlipidemia, and vasoconstriction. The reverse of those effects occurs simply by increasing the proportion of omega-3 fats.

Is there a dark side to omega 3s?

EPA and DHA have a well-documented ability to suppress the body’s immune response. Although not as consistent as the immune effects, data also exist on the ability of EPA and DHA to increase bleeding time and oxidation.

Quick hits:

Fish oil is one of the few supplements that actually have a substantial body of scientific evidence backing it up.

It’s common and perfectly acceptable for products to contain slightly more EPA than DHA.

I would also error on the side of safety and keep [fish oil pills] refrigerated.

There’s a widespread belief that ALA from flaxseed is worthless for increasing EPA/DHA since the conversion is inefficient. However, Harper’s team recently observed 3g ALA/day (from 5.2g flaxseed oil) raise plasma EPA levels by 60% at the end of a 12-week trial [22].

Aragon's summary:  Looking at the body of evidence as a whole, fish oil (or increased fish consumption) has great potential for improving cardiovascular health. But for reducing body fat, the effects are minor to nonexistent.