By Dr. Mercola
For many years now, my favorite source of omega-3 fats has been krill oil. Every time a new study about krill oil hits the journals, its list of health benefits grows longer and the differences between fish oil and krill oil become more pronounced.
Krill oil is often compared to fish oil as a source of animal-based omega-3 fats.
But krill consistently comes out on top in the research—and the latest study published in the July 2011 issue of Frontiers in Geneticsi is no exception. This study compared the livers of mice fed krill oil to those fed fish oil by looking at the gene expression triggered by each.
Researchers found that krill oil is VASTLY superior to fish oil when it comes to influencing your genes. What do your genes have to do with your metabolism? Everything! Every aspect of your metabolism is controlled by how your genes express themselves.
New Study Shows Krill Oil Flips on Key Metabolic Genes
Genes have "switches" that can be flipped on and off, which control virtually every biochemical process in your body. And nutrients like omega-3 fats control those switches. Your liver plays a major role in controlling how your body uses carbohydrates and lipids, utilizing omega-3 and omega-6 fats to sense your nutritional state and influence gene expression accordingly.
Fatty acids help to direct key metabolic processes such as glucose production, lipid synthesis, cellular energy, oxidation, and dozens of others. We now know that various types and sources of omega-3 fat affect liver tissue differently, which is what this study was designed to examine.
Krill oil actually influences your metabolism and genes to improve! The referenced study found that, although both fish oil and krill oil contain omega-3s, they differ greatly in how they affect the genes controlling your metabolism. Krill oil:
- Enhances glucose metabolism in your liver, whereas fish oil does not
- Promotes lipid metabolism, whereas fish oil does not
- Helps regulate the mitochondrial respiratory chain, whereas fish oil does not
- Decreases cholesterol synthesis, whereas fish oil increases it
So, krill will help lower your triglyceride and cholesterol levels and increase your energy production, whereas fish oil does neither and in fact may even raise your cholesterol level, according to the latest research. According to the researchers:
"Elevated hepatic glucose production is associated with metabolic disease in humans (Natali and Ferrannini, 2006), and we observed that krill oil supplementation favorably alters the expression of genes regulating hepatic glucose metabolism."
Prior studies show that krill oil may lower your blood glucose level by increasing glucose uptake by tissues other than your liver. In another study that directly compared krill oil with fish oil, krill oil was significantly more effective in reducing liver triglyceride levels. These studies all suggest krill oil may offer significant benefits for those with the metabolic dysregulation seen in obesity and type 2 diabetes—which is a problem of epidemic proportions in today's world.
Omega-3 fats affect your cellular health and DNA chiefly by how they influence your cell membranes. It is these cell membranes that are critical in switching your genes on and off, because the membranes contain receptors that respond to hormones and other agents, and these are affected by the fatty acids on their surface. Your cell membranes contain EPA, DHA and phospholipids, and all help to shuttle molecules into and out of your cells. Therefore, having ample high quality fatty acids in your system is crucial to keeping your cell membranes working like well-oiled little machines.
Other Advantages of Krill
It is important to understand that krill oil has a number of other advantages over fish oil:
- Some studies have shown that krill oil may be 48 times more potent than fish oil. This means you need far less of it than fish oil, as confirmed by a 2011 study published in the journal Lipidsii.
- This is because krill oil contains phospholipids, so the omega-3 fats are already in the form that your body can use. This bioavailability means krill oil is absorbed very quickly and crosses your blood-brain barrier, so is able to reach important brain structures. Also, phospholipids are one of the principle compounds in high-density lipoproteins (HDL), which you want more of.
- Fish oil is quite prone to oxidation, and oxidation leads to the formation of free radicals. Consuming free radicals further increases your need for antioxidants. Fish oil is weak in antioxidant content, whereas krill oil is rich in antioxidants. Krill oil contains astaxanthin—probably the most potent antioxidant in nature—which is why it is so stable and resistant to oxidation.
- Many, if not most, fish and fish oil are now contaminated with mercury and other heavy metals; even fish that is thousands of miles away from coal plants and other environment-polluting industries. Antarctic krill is not prone to this contamination.
- Krill is also far more sustainable as a food source than is fish because it's the largest biomass in the world, making krill harvesting one of the most sustainable practices on the planet.
Could Omega-3 Deficiency be Killing More People than Breast Cancer?
Three studies in 2009 showed that omega-3 fat deficiency might cause or contribute to up to 96,000 premature deaths each year. Compare that number to the estimated 40,000 women who die from breast cancer in the U.S. annuallyiii, and the implications of omega-3 deficiency become quite clear.
Omega-3 fats from krill have been shown to be far more effective than fish oil in reducing fat levels in your heart and liver. The latest study adds to the mountain of research that krill oil can lower your risk for metabolic syndrome, obesity, type-2 diabetes, and cardiovascular disease.
In one study, krill oil was found to reduce fat levels in the hearts of rats by 42 percent, compared to just two percent for fish oil. Similarly, krill was found to reduce fat in the liver by 60 percent, compared to 38 percent for fish oil. The buildup of fat in your liver can lead to insulin sensitivity, metabolic syndrome and eventually full-blown type 2 diabetes, just as the buildup of fat in your heart can predispose you to a heart attack.
Krill Oil Can Also Help Protect Your Brain
Some omega-3 fats—especially DHA—are critical for your nervous system, particularly your brain. DHA is converted into substances called neuroprotectins. Alzheimer's disease is associated with a shortage of these neuroprotectins. Fats make up about two-thirds of your brain tissue. Myelin, the protective sheath that covers your neurons, is composed of 30 percent protein and 70 percent fat. These fats are not just important for adults. Omega-3s are crucial for proper brain and eye development in infants and children.
Two different studies have shown that taking 800 to 900 mg of DHA per day for 16 to 24 weeks resulted in significant improvements in memory, verbal fluency scores, and rate of learning.
Low concentrations of EPA and DHA are known to accelerate cognitive decline and increase your risk for mood swings and mood disorders. Those suffering from depression have been found to have lower levels of omega-3 in their blood, compared to nondepressed individuals. A 2010 study involving 46 depressed elderly womeniv concluded that omega-3 supplementation can improve quality of life and effectively treat depression.
According to a report published in 2007 in the Alternative Medicine Reviewv, DHA and EPA in krill oil can lessen a variety of brain and mental disorders, including autism and dyslexia. DHA also protects your cells from gene mutations that can lead to brain diseases such as Parkinson's and some forms of Alzheimer's disease, by preventing "misfolding" of certain proteins that occur as a result of those mutations.
Krill Oil is a Potent Anti-Inflammatory
A major reason krill oil has such impressive benefits is that it powerfully reduces inflammation in your body. They produce compounds called resolvins and protectins, which help quell inflammation before it can do too much damage to your tissues. Several studies have been published on the remarkable effectiveness of krill oil in combating inflammation-related disorders, such as arthritis.
One 2011 study in the Journal of Clinical Nutrition found that women with the highest omega-3 levels had a 44 percent reduced risk of dying from inflammatory diseases. Studies have proven krill oil's ability to reduce pain, stiffness, and functional impairment in people with inflammatory disorders in just one to two weeksvi and reduce the symptoms for both rheumatoid and osteoarthritis sufferersvii, viii.
The Verdict is in: Krill Oil May Help with Literally DOZENS of Diseases
GreenMedInfo.com now lists more than than 25 different diseases krill may help prevent or reverse. Of course, if you extend the search to include everything related to omega-3 fats, the list of benefits expands even more, since the gifts of krill oil include everything known to be good about omega-3s. The implications are truly profound, and I'm sure you'll be seeing much more krill research in the future. The following table includes links to a number of studiesspecific to krill oil, by disease. There is much more information about krill and omega-3 fats on the GreenMedInfo website.
A Final Note on Krill Oil Supplements
Please remember that I don't advocate taking large amounts of supplements. It is far better to receive you nutrients from food. If it weren't for the polluted waterways of the world, I would recommend getting your omega-3 fats from fish rather than supplements, but unfortunately, most fish are now so contaminated with mercury and other toxins, I just cannot recommend it any longer.
As you can see from the research above, animal-based omega-3 fats are essential for optimal health. I recommend you consider taking a high quality omega-3 supplement, and I think krill oil is your best option.
The only kind of krill oil I recommend is from genuine Antarctic krill. Look for a brand that is cold-processed, which preserves its biological benefits. Please make sure that hexane is not used to extract the oil from the krill as some of the most popular krill oils on the market use this dangerous chemical agent. It should also be free of heavy metals, PCBs, dioxins and other contaminants. You should also make sure the krill you take is harvested in compliance with international conservation standards.