By Dr. Mercola
If you've been a long-time reader of my site, then you probably know just how much I value getting sufficient omega-3 fats in your diet. In a perfect world, you can get all the omega-3s you need from fish, but because majority of the fish supply is now contaminated with heavy metals like mercury, then you'll have to resort to other sources to provide you with this valuable nutrient.
One of my personal favorites for omega-3 supplementation is high-quality krill oil. In this article, you'll discover the wealth of benefits you can get from krill oil, the ideal dosage for your health requirements and why it's a hundred times better than typical fish oil.
What Is Krill Oil and Where Does It Come From?
Krill oil is a marine oil that is known for providing animal-based omega-3 fats, antioxidants and beneficial substances known as phospholipids1 – this last item is particularly important, as it plays a significant role in the absorption of these nutrients (more about this later). It is harvested from krill (Euphausia superba), a small shrimp-like crustacean.
The humble krill only measures about two inches in length – but don't let its size fool you. Krill is a crucial component of the global food chain, as it serves as the fuel that keeps the Earth's marine ecosystems consistently running. While it feeds on microscopic, single-celled plants called phytoplankton, hundreds of different creatures – birds, squids, other fish and even whales – feed on krill in turn.
There's said to be 85 known krill species, with the numbers ranging from 125 million to 6 billion tons around Antarctica (although they're also found in oceans off of Japan and Canada2). At specific times in a year, the krill congregate in very dense swarms that they can be visible from space.3
Aside from being highly sustainable, krill are also known for their longevity – they can live from five to 10 years,4 which is amazing, considering they're very heavily hunted. This is why Antarctic krill oil is a good and eco-friendly choice for an omega-3 supplement.
Krill Oil Versus Fish Oil: What Makes It Stand Out
As opposed to krill oil, fish oil is extracted from oily, cold-water fish, particularly their liver. Common examples of fish oil sources are herring, halibut, mackerel, salmon, albacore tuna and cod, which may be deep-ocean farmed or wild-caught. In some instances, fish oil is extracted from seal or whale blubber.5
While often interchanged, there are also notable differences between the two; yet if you thoroughly examine them, you'll note that krill is surely the superior option. Here are some reasons why krill oil is better than fish oil:
Has a higher potency – Krill oil not only has 48 times the antioxidants as fish oil, but also has a higher potency in its metabolic effects, meaning you need far less to reap the benefits.
One study published in the Lipids journal confirms this, wherein subjects taking krill oil only required 63 percent of what those taking fish oil had to consume to achieve the same results.6
Is free of contaminants – The fish from which fish oil is extracted are often contaminated with heavy metals and mercury.
Krill does not pose this risk because of their small size and due to the fact that they're at the bottom of the food chain.
Has phospholipids – As mentioned, the phospholipid factor definitely plays a significant role in how krill oil is absorbed by your body.
Omega-3 fatty acids are water-soluble but cannot be transported in your blood while in their free form.
Thus, they need phospholipids – something that krill oil readily has, but fish oil doesn't. This is why krill oil is 10 to 15 times better absorbed than fish oil.
Contains phosphatidylcholine – Composed partly of choline, a precursor for acetylcholine that sends nerve signals to your brain, and trimethylglycine, which has liver-protective effects, phosphatidylcholine is necessary for better absorption of omega-3 nutrients.
If you opt for fish oil, your liver still needs to find and attach it to phosphatidylcholine, so that it can be better utilized. But since krill oil already has phosphatidylcholine, it's then more superior in terms of bioavailability.
Is less prone to oxidation – Krill oil has astaxanthin, making it more stable and less likely to oxidize in your body.
Meanwhile, fish oil, which does not have astaxanthin, is more prone to oxidation, leading to the formation of free radicals, and increasing your need for antioxidants.
More environmentally sustainable – Krill harvesting is a stringently monitored process, and while there are claims saying that krill oil supplements are depleting the ocean's supply, the fact is that only 1 to 2 percent of the overall krill biomass is harvested per year.
Another research also found that krill is superior to fish oil in terms of its influence on genetic expression and metabolism. A 2011 study published in the journal Frontiers in Genetics took a look at the livers of mice given krill oil versus those fed fish oil.7 The researchers found that krill oil enhances glucose metabolism in the liver, promotes lipid metabolism and helps regulate the mitochondrial respiratory chain – all of these effects are not seen in the fish oil group.
Furthermore, krill oil decreases cholesterol synthesis, while fish oil increases it. This means that krill oil will help lower your cholesterol and triglyceride levels and increase energy production, but fish oil does not offer either of these benefits. Yet, this is just the tip of the iceberg in terms of how krill oil does wonders for your body.
How Does Your Body Use the Omega-3s From Krill Oil?
What primarily gives krill oil its many health advantages is its omega-3 fatty acids. Omega-3s are polyunsaturated fatty acids (PUFAs) that are used by your body for various functions, such as digestion, blood clotting, muscle activity, memory and cognitive function, visual acuity and much more. They are also particularly important for proper cell division and function of cell receptors.
However, your body cannot produce omega-3s, hence, they need to be acquired from your diet. Most people would contest that omega-3s can be derived from plant sources too, like chia, hemp and flaxseeds, but the omega-3s that you get from krill oil and fish are far more beneficial.
This is because the omega-3s in plant foods are in the form of alpha-linolenic acid (ALA). ALAs are short-chained PUFAs that need a particular enzyme for them to be converted to eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) – long-chain PUFAs that are more bioavailable and beneficial.
Norwegian scientist Nils Hoem, PhD., who specializes in omega-3 phospholipids, explains it further. According to him, short-chain fatty acids are simply food that provide a source of energy for the body. Meanwhile, long-chain PUFAs like EPA and DHA are structural elements that are the building blocks of your cells. This is the most significant difference between these two types of omega-3s.
EPA and DHA are known for their numerous biological effects, particularly their anti-inflammatory benefits. Plus, they play a role in communication within the cell and between the cells. DHA in particular is very essential, since it's a component of every cell in your body and is crucial to brain health.
Please take note that I'm not vilifying plant-based omega-3s. ALA is a very healthy fat with its own useful purpose. Your body needs it – but not in excessive amounts and not as crucially as EPA and DHA, which come from krill and other sources.
Krill Oil's Many Health Benefits
So what exactly does krill oil do for your health? For starters, it's been said to help with at least two dozen diseases and health issues, such as:
Cardiovascular disease and hyperlipidemia (Krill oil may help lower blood pressure, triglyceride levels and LDL (bad) cholesterol levels, while raising HDL (good) cholesterol levels)8,9
Neurological/cognitive dysfunction (This includes brain aging, memory loss and learning disorders. It may also be helpful for ADHD, dyslexia and autism, as well as Parkinson's disease)
Inflammation – It also helps reduce C-reactive protein10
Osteoarthritis and rheumatoid arthritis (RA)12,13
Metabolic syndrome,14(This includes obesity, type 2 diabetes and fatty liver)
Dysmenorrhea and premenstrual syndrome (PMS)15
Preventing premature delivery and promoting brain development in infants
Autoimmune diseases like nephropathy and lupus
Of course, if you include omega-3 fats in the equation, then this list would greatly expand. In particular, omega-3s may help:
• Improve endothelial function (which helps promote growth of new blood vessels)
• Boost your mood
• Reduce your risk of Alzheimer's disease
• Maintain bone health
• Reduce your risk of death from all causes
Studies on Krill Oil Confirm Its Potency
Many of the mentioned benefits above have been well-backed by scientific research. Here are a few notable examples:
• Reduced cholesterol levels - An animal study published in the Journal of Animal Physiology and Animal Nutrition found that rats given krill oil supplements for six weeks reduced their cholesterol levels by 33 percent.18 In a separate study,19 this time conducted on patients taking statins, taking krill oil along with statins and a low-fat diet reduced cholesterol levels by 20 percent.
• Improvements in osteoarthritis and RA patients – A study conducted on patients with these ailments found that those who took 300 mg of krill oil daily had reduced pain, inflammation, stiffness and functional impairment after just seven days. Better improvements were seen after 14 days.20
• Metabolic syndrome – A rat study looked at the risk factors linked to metabolic syndrome, particularly endocannabinoids, which stimulate your cannabinoid receptors and produce a variety of physiologic processes. The researchers found that mice that had increased endocannabinoid levels (after being fed an unhealthy diet) had a significant reduction after taking krill oil.21
Krill Oil Dosage: What's the Ideal Amount?
One study concluded that a daily dose of krill oil at 300 milligrams can already provide anti-inflammatory benefits.22 However, much higher doses, up to 1,000 mg, may be safe for adults. I recommend consulting the product label on your krill oil supplement to find out the ideal dose for your age.
You should also take a krill oil supplement that's recommended for your age group. For example, there are particular krill oil supplements that are specifically made for children. Ideally, take krill oil in the morning or with your first meal of the day.
Krill Oil May Have Some Side Effects
One of the most common complaints against fish oil is that it leaves behind a fishy aftertaste or results in reflux or belching of fishy flavors.23 However, this effect is significantly reduced in krill oil, as long as you purchase a high-quality brand. Even so, take note that some krill oil brands (particularly poor quality ones) may also cause side effects like heartburn, upset stomach, bad breath, nausea and loose stools.24
While krill oil is generally safe for most people, it is still important to consult your physician if you are suffering from any illness or taking any medication before taking this supplement (or any dietary supplement). Krill oil is also safe to take (and even an advantage) for pregnant women and breastfeeding mothers, however, consult your physician prior to taking it.
If you are taking anti-coagulants like Warfarin or any other blood thinners, or have a blood coagulation disorder, do not take krill oil. There may be dangers as well for people who have allergies to seafood who take krill oil.
The Best Sources of Krill Oil: Here's What to Look for When Buying This Supplement
When looking for a krill oil supplement, I advise that you only purchase one that has been certified by the Marine Stewardship Council (MSC). This non-profit organization aims to transform the seafood market to a sustainable basis and it does this by recognizing and rewarding fisheries that follow sustainable fishing practices.
When the krill oil is MSC-certified, it means that every part of the manufacturing process – from the krill harvesting to how it is manufactured – has gone through a high global standard, ensuring that the product is truly sustainable. The MSC also has a chain of custody traceability program, which seafood providers can renew on a yearly basis. In additional, keep an eye out for these other factors:
• The krill oil must be produced using Antarctic krill, which is the most abundant.
• It should be free of heavy metals, dioxins, PCBs and other contaminants.
• It should be cold-processed, which preserves its biological benefits. Avoid krill products that use hexane to extract the oil – unfortunately, many popular krill oil brands use this dangerous chemical agent.
• The krill oil should be encased in hard capsules instead of soft gels, as the latter allows more oxygen to enter, promoting oxidation. Even if krill oil naturally contains astaxanthin that can reduce oxidation, these hard capsules add another protective layer, giving you a product that's optimally fresh and effective.
Krill Is King When It Comes to Omega-3s, but Here's Another Great Choice You Can Try
A high-quality krill oil supplement outperforms fish oil in terms of efficiency, sustainability and cost. However, you may also want to get this valuable nutrient from certain types of seafood, particularly those that have not been contaminated with heavy metals and other pollutants. One of the best sources is wild-caught Alaskan salmon. Small fish types like anchovies and sardines are also wonderful options, and is highly recommended for those who truly need an omega-3 boost.
Frequently Asked Questions (FAQs) About Krill Oil
Q: Is krill oil safe?
A: Yes, krill oil is generally safe for most people. However, certain individuals, such as those who have seafood allergies, have a blood clotting disorder or taking anticoagulants must refrain from using this supplement, as it can have severe effects on their health.
Q: What is krill oil used to treat?
A: Over two dozen health conditions are said to benefit from krill oil, including cardiovascular disease, osteoarthritis and rheumatoid arthritis, kidney disease, cognitive or neurological dysfunction and autoimmune diseases.
Q: How much krill oil should you take per day?
A: One study found that 300 mg of krill oil per day can already provide you with anti-inflammatory benefits.25 However, taking higher doses up to 1,000 mg may be safe for adults as well. Please consult the product label to find out the ideal dose for your age.
Q: Can krill oil cause heartburn?
A: Some krill oil brands may cause heartburn. To avoid this, take krill oil along with a full meal. If this does not work, try reducing the dose or stop taking the product for a while.26
Q: Is there mercury in krill oil?
A: There is no mercury in krill oil. This is because krill, which is at the bottom of the food chain, feeds on phytoplankton. It does not consume mercury-contaminated fish.
Q: Is krill oil the same as omega-3?
A: Krill oil is a marine oil extracted from krill, a shrimp-like crustacean, while omega-3s are polyunsaturated fatty acids (PUFAs) that are used by your body for various functions. Hence, krill oil is not directly synonymous to omega-3s, technically speaking, but it does contain these beneficial fatty acids, particularly DHA and EPA.