The Fish Oil - Styrofoam Battles

Putting a competitor’s fish oil (omega-3 fatty acids) capsule in a styrofoam cup and having an audience watch the cup disintegrate is a bizarre demonstration that has, for several years, been played around the world by many multilevel marketers.

Styrofoam is soluble in many organic compounds including acetone and fish oil, although its rate of solubility in these compounds may differ.

The claim of superiority for their product only invited the competition to rebut by equating the solubilising capacity on styrofoam to solubilising cholesterol* in the body. This led to the challenger(s) raising fears of the dissolved styrofoam causing cancer which then necessitated the intervention of the health authorities.

There are two types of omega-3 fatty acids on the market for human consumption based on the chemical structure: those in triglyceride (TG) form and those in ethyl ester (EE) form.

Omega-3 fatty acids naturally exist in TG form, while those in EE form are obtained from the TG form by molecular distillation.

The benefits of having omega-3 fatty acids in EE form are two-fold.

First, since it is synthesized from fish oil that goes through several purification steps, the EE form does not contain any contaminants, which are of concern when consuming fish [1].

The second benefit is that the EE form can be highly concentrated (it could be as pure as 98% EPA and DHA) and these concentrated forms are often used for therapeutic applications [2].

In a further purification step, EEs can be converted back into their natural TG state. This additional step incurs extra cost, thus the higher price that the processors demand.

However, the re-esterified fish oil does not automatically qualify as pharmaceutical grade. Stringent control of not only the purification process but also the manufacturing facilities and environment and the concentration of EPA and DHA and the impurities is required to meet the standards set by the European Pharmacopoeia.

Interestingly, GlaxoSmithKline's Lovaza, currently the only FDA-approved fish oil, is available in the EE form. The reason is simple, all available clinical data on human trials to support its application for registration as a prescription drug is based on the EE form. Lovaza is not yet available in our country.

Research examining the bioavailability of the two omega-3 fatty acid forms showed that they are both readily digested in the intestines and absorbed and incorporated into the body's lipid system.

Krokan and coworkers studied the enteral absorption of EPA and DHA in EE form in comparison to natural fish oil (in TG form) of equivalent doses in healthy male volunteers for 14 days and concluded that there was no difference in enteral bioavailability of EPA and DHA from either the synthetic EE of EPA + DHA or the natural fish oil [3].

However, Dyerberg J et al [4] recently working with 72 apparently healthy volunteers found that the 24 volunteers who were put on re-esterified fish oil had improved blood levels of eicosapentaenoic acid (EPA) plus docosahexaenoic acid (DHA) compared to the rest who were on natural fish oil and EE fish oil.

From a nutritionist's point of view, regardless of the chemical forms of these omega-3 fatty acids, they are all well absorbed and utilized in the body. Even though there are discrepancies in regard to their absorption and organ incorporation in the literature, we must keep in mind that there are numerous factors that could influence this in the human body, such as the composition of the meal (especially the fat content), one's physical and heath status and age as examples.

Since omega-3 fatty acids in supplements are well tolerated by humans, slight variation in their bioavailability should not be a significant concern for casual consumers who aim to meet the daily recommended omega-3 fatty acid intakes for health maintenance and preventive care. The choice of one form of fish oil over the other is only a matter of affordability.

However, for therapeutic purposes, more precise dosing is required considering the target health problem, subject's age and health status, and if there are any complications that need to be addressed (e.g., drug interactions).

Aside from complicated applications of therapeutic uses of high purity omega-3 fatty acids, health supplements containing fish oil do provide a convenient way for consumers to meet the daily recommended intake levels of this group of essential fatty acids.

References

[1] Most of the widely available supplements contain little or no mercury, dioxins or PCBs. Test results for various fish oils can be found on the International Fish Oil Standards Web site.

[2] Yong Li and Bruce A. Watkins. Bioavailability of omega-3 fatty acids in fortified food products. Purdue University.

[3] Krokan HE, Bjerve KS, Mork E. The enteral bioavailability of eicosapentaenoic acid and docosahexaenoic acid is as good from ethyl esters as from glyceryl esters in spite of lower hydrolytic rates by pancreatic lipase in vitro. Biochim Biophys Acta 1993;1168:59-67.

[4] Dyerberg J, Madsen P, Møller JM, Aardestrup I, Schmidt EB. Bioavailability of marine n-3 fatty acid formulations. Prostaglandins Leukot Essent Fatty Acids. 2010 Jul 16. [Epub ahead of print]

* DOES FISH OIL DISSOLVE CHOLESTEROL?

Triglycerides and cholesterol are separate types of lipids that circulate in your blood.

Blood level of trigylcerides and cholesterol (usually of high density lipoprotein cholesterol— often called good cholesterol and low density lipoprotein cholesterol —often called bad cholesterol) is often used as an indicator of whether someone is likely to have a heart attack or stroke caused by blockage of blood vessels or hardening of the arteries (atherosclerois).

Although it's unclear how, high triglycerides may contribute to hardening of the arteries or thickening of the artery walls (atherosclerosis) — which increases the risk of stroke, heart attack and heart disease.

Fish oil lowers triglycerides level and is used together with diet and exercise to slow or prevent the accumulation of fat in the inner lining of your blood vessels.

Recent evidence from cellular and molecular research studies indicates that the cardioprotective effects of omega-3 fatty acids result from a synergism between multiple, intricate mechanisms.

These mechanisms involve antiinflammation, proresolving lipid mediators, modulation of cardiac ion channels, reduction of triglycerides, influence on membrane microdomains and downstream cell signaling pathways and antithrombotic and antiarrhythmic effects.

(Adkins Y, Kelley DS. Mechanisms underlying the cardioprotective effects of omega-3 polyunsaturated fatty acids. Journal of Nutritional Biochemistry published online 12 April 2010)

THE BOTTOM LINE

The fish oil market has boomed in recent years, riding on a wave of studies pointing to the cognitive and heart health benefits of the lipid ingredient. You can expect more colourful but confusing battles between multilevel marketers of fish oil as they compete for market share. This only underscores the importance of seeking the advice of health professionals like doctors and pharmacists on health supplements.