Some articles you will find on the Internet tell you that krill oil can be dangerous to take. Be a smart consumer and be aware that much of what you read on the web is opinion based or marketing based, not science based. Some articles we have seen raising fears about krill oil are doing so because they are small entrepreneurs trying to convince you to buy their fish oil product.
The potential for side effects from taking krill oil is very low, with a few exceptions, of which we make note below. The phospholipids and antioxidants typical to krill oil have been consumed by humans for centuries. Individual components, such has EPA, DHA, astaxanthin and choline have a well established need and safety profile. The EPA, DHA, and choline components can be considered conditionally essential, which means they are essential under some circumstances — our bodies cannot make enough to meet biological needs. Krill oil has also achieved affirmed GRAS status with the FDA. This means that krill oil is Generally Recognized as Safe (more on this below).
Each supplier of krill oil (as well as fish oil) must produce something called a Certificate of Analysis – an authenticated document issued by an accredited firm or individual that certifies the product has been tested for quality and purity. So, what kind of testing is done?
Microbes and krill oil
One level of testing is aimed at microbial testing, that is making sure that there is no salmonella, E. Coli or staphylococcus in the product. These are very bad contaminants and must not be detectable by standards established by the Food and Drug Administration. You may want to consider this: If you have a bottle of capsules and pour them out into your hand to remove one or several, you are actually adding various degrees of contamination from your hands to what is left in the bottle. This is why you may want to consider buying your supplements in blister packs, which isolate each capsule from the next.
Beyond these, testing is done for yeast, mold and water, which must not be present at all, or in no greater than amounts that are established as safe.
Oxidation and krill oil
Essential fatty acids, such as are found in krill oil, are susceptible to natural oxidation. This means their molecules begin to lose electrons. This is what happens to polyunsaturated oils when they begin to go rancid. The presence of antioxidants arrests this process. Krill oil contains a powerful antioxidant, astaxanthin, because krill eat Antarctic algae, which is very rich in the astaxanthin found underneath the sea ice.
Vitamin E, another antioxidant, is also present in krill oil formulations, some brands more than others. Vitamin E, which is not naturally present in fish oil and therefore must be added, is the first antioxidant to begin to arrest the oxidation process. Generally, the quantity of astaxanthin digested in the process of fighting oxidation in krill oil supplements is about 5-10 percent per year. Some brands have as little as 0.1mg, whereas others have as much as 4mg per gram of oil.
There are tests for rancidity, as well. Rancidity level in krill oil is tested using a measure that is stated as a number indicating “totox value.” In order to be compliant with standards established by GOED (The Global Organization for EPA and DHA Omega-3), totox value must not be more than 26. The krill oil being produced by one supplier, Azantis, for instance, has a tested totox value of 14.8, far below the necessary threshold.
Heavy metals and krill oil
As for contamination with heavy metals (lead, mercury, arsenic, etc), there are standards set by the United Nations World Health Organization, the Environmental Protection Agency and others as to how many parts per million any substance that is to be ingested can contain. There has been a growing public awareness about the content of such contaminants in seafood of all kinds. The major sources of mercury in virtually all the world’s oceans (including the Antarctic) include the world’s coal-burning power plants, automobile emissions, and gold and mercury mining. Because of these, mercury can now be found in virtually all seafood in varying amounts. As for dioxins, It is estimated that 96 percent of those present in the environment originate from air emissions.
The major problem with such contaminants is that they persist in the environment and accumulate in the food chain – smaller fish are eaten by bigger ones, which are then eaten by bigger ones, and so on, until the concentrations reach levels dangerous to the human system.
So, what about krill? Because krill is at the very bottom of the food chain, and because krill eat algae, these contaminants don’t accumulate in the krill’s system as much as they do in predators higher up the food chain.
Krill oil products are relatively free of dioxins and PCBs. This is, in part, due to the krill’s place in the food chain – it does not readily accumulate toxins. Consider this: Krill has a short life span, perhaps as short as two years, and reproduces quickly, replacing the biomass. Compare this with Bluefin tuna, which lives for many years and eats a lifetime’s worth of fish from lower on the food chain. The amount of these contaminants in seafood is really dependent on where in the food chain they exist and how long they live.
Proper krill oil processing also serves to reduce PCB contaminants. In general, krill suppliers should be, and are probably testing their product for dioxins and PCBs. One krill oil supplier reports that their krill contains PCBs in the very low parts per trillion level (ppt), and below detection for some of the more harmful PCBs. The US Food and Drug Administration has set the tolerance level for PCBs in fish at 2 parts per million(ppm). The nearly undetectable levels of PCB in krill supplements easily fall within the FDA safety standards. In fact, you are likely to consume more PCBs in a serving of fish than in a capsule of krill oil. If you are concerned about PCBs, you should check with your supplier for a statement of PCB content.
Read much more about the subject of krill oil and PCBs here, as well as the controversy surrounding a California Proposition 65 lawsuit against fish oil and krill oil makers.
GRAS status for krill oil
Several krill oil producers have sought and achieved what is called GRAS status (Generally Recognized as Safe) with the U.S. Food and Drug Administration. GRAS status allows an ingredient to be used as an additive to foods. Krill oil components – such as phospholipids, choline, and astaxanthin – are all GRAS ingredients. Krill oil itself has now been recognized as GRAS, and is being used in development of medical foods and as a food ingredient.
An ingredient with GRAS status is not subject to premarket review and approval, if it meets certain qualifications. There are two pathways for achieving GRAS status (for something that is not on the grandfathered GRAS list): GRAS Notification and GRAS Affirmation. The latter is an expensive process ($50,000-$70,000) that involves assembling a panel of qualified experts who review the science and declare that the ingredient is adequately shown to be safe under the conditions of its intended use. The FDA looks at the facts and opinions, and issues its statement.
GRAS Notification requires that a company notify the FDA of its intention to use the product in food, and show that it is safe under the conditions of its intended use. The FDA looks at the facts and opinions, and issues a statement that it either doesn’t question the basis for the notifier’s GRAS determination, or that the notice doesn’t provide a sufficient basis for GRAS status (indicating it may have questions about the safety of the substance).
To date, one krill oil provider has achieved GRAS Notification for its product, and another has received GRAS Affirmation.
Krill oil is safe to take
All the components within krill oil are safe (but see "Precautions" below). As with all supplements, obtain your krill oil from a quality manufacturer that is willing to follow the standards set for fish oils, as well as adopting the newest standards set by GOED. They should be willing to submit a statement of purity, based on their certificate of analysis.
There will likely be products on the market of lower quality. If you do just a little homework and look for products that have been carefully tested, you will be able to be able to derive the benefit inherent in this unique product.
One important tip: for greatest efficacy, check the ‘use by’ date on the label. The amounts of nutrients stated on the label are meant to reflect what should be in the krill oil after two years of shelf life, so be sure the 'use by' date must not have been past.
Another good tip: Don't refrigerate krill oil. The cold air begins to break down the gelatin capsules, which will cause the inner liquid to leak out, and many will consider the odor to be unpleasant.
Krill oil precautions or negatives
So far, the only dangers hinted at in krill oil research are if you are taking anti-coagulants such as Warfarin (Coumadin) or high-dose aspirin, due to the blood-thinning properties of krill oil. Therefore, suppliers routinely recommend consulting a physician and undergoing testing prior to using krill oil – it's a lawyer thing. But if you have a seafood allergy, or if you’re pregnant or breastfeeding, it really would be wise to at least consult a physician before taking krill oil.