Krill are small crustaceans that live in oceans all over the world. Similar in appearance to shrimp, krill are an important link within the food chain since they feed primarily on phytoplankton, and in turn, are fed upon by whales, seals, penguins, squid, and fish.
Derived from the tissues of the Antarctic species (Euphausia superba), krill oil provides similar health benefits as fish oil but is considered to be easier for the body to absorb, is more sustainably fished, and is less likely to be contaminated with mercury and other heavy metals since they are on the bottom of the food chain.
Krill oil is also structurally and chemically unique, with a distinct mechanism of action and a range of antioxidants not found in typical fish oils.
Read on to discover the phenomenal health benefits of krill oil:
1. Krill Oil is an Excellent Source of Omega-3 Fatty Acids
Omega-3 fatty acids play an integral role in the function of cell membranes throughout the body. They help make hormones, bind to receptors to regulate genetic function, and modulate inflammatory processes. These polyunsaturated fats have been widely studied for their potential health benefits which include cardioprotective properties, infant neuro development, protection from cognitive decline, and cancer prevention.
Because the human body cannot synthesize omega-3 fatty acids, we must obtain them from food or dietary supplements. Two types of omega-3 fats – Eicosapentaenoic acid (EPA) and Docosahexaenoic acid (DHA) – are present only in fish and other marine animals.
Although eating seafood or supplementing with fish oils will provide both EPA and DHA, krill offers an alternate (and sometimes superior) source of these omega-3 fats. Compared with other fish, krill is composed of 17.4% EPA – higher than trout (4.8%), salmon (7.2%) and shrimp (14.9%). The DHA value of krill is 12.4%, higher than trout and salmon, and only slightly below shrimp.
One important distinction between fish oil and krill oil is bioavailability. Studies on the absorption of DHA and EPA in humans and animals indicate that the bioavailability of krill oil is higher than that of fish oil.
The enhanced absorption of krill oil may be due to its mechanism of delivery. While the omega-3 fats in fish are delivered via triglycerides (fats the body uses for energy), krill’s EPA and DHA content is bound to phospholipids – a type of lipid found in cells. Phospholipid omega-3 fatty acids are water loving and disperse easily in stomach fluids. Triglyceride omega-3s, on the other hand, are hydrophobic, don’t disperse quickly, and tend to float on top of stomach fluids.
2. Krill Oil is Rich in Antioxidants
According to an analysis published in Nutrition Reviews, each 100 gram serving of krill contains the recommended daily value for vitamin E and vitamin B12, with lesser amounts of vitamin A, riboflavin, niacin, folate, and vitamin B6.
Krill is also a rich source of astaxanthin, a type of carotenoid with a blood red hue. It originates in microalgae and yeast fungus that undergo stressful conditions (lack of nutrients, increased salinity in the waters, and excess sunshine), creating astaxanthin. When sea creatures, like shrimp, crab, salmon, and krill, consume the microalgae, it alters their appearance to give them their red or pink coloring.
Astaxanthin is a potent antioxidant with a several-fold stronger free radical scavenging activity than vitamin E and beta carotene. A review of the health benefits of astaxanthin found that it provides photo protection against UV light, preserves eye and skin health, fights inflammation, boosts immune response, protects against neurodegenerative diseases, bolsters heart health, and possesses anti-cancer properties.
3. Krill Oil for Chronic Inflammation
While acute inflammation in essential to the healing process during an infection or injury, chronic inflammation, lasting many months or years, can do long-term damage to your heart, brain, and other organs. Prolonged inflammatory processes in the body have been linked to heart disease, cancer, and Alzheimer’s disease.
In a study published in 2007, researchers recruited 90 patients diagnosed with one or a combination of cardiovascular disease, rheumatoid arthritis, and osteoarthritis to determine the effect of krill oil on inflammatory conditions. The participants were provided with 300 mg of krill oil daily, to be taken over the course of 30 days.
Measuring C-reactive protein (CRP), a marker for inflammation in the blood, krill oil reduced CRP by over 19% in 7 days and more than 30% by day 30. Compared to the placebo group, CRP levels had increased by 25% in the same period. Additionally, the krill group reported a 28.9% reduction in pain, a 20.3% reduction in stiffness, and a 22.8% reduction in functional impairments – in just one week.
4. Krill Oil is Cardioprotective
Omega-3 fatty acids have been extensively studied for their effects on heart health. Both EPA and DHA have been found to reduce a number of risk factors associated with coronary heart disease, including preventing arrhythmias, lowering heart rate and blood pressure, decreasing platelet aggregation, and reducing triglyceride levels.
Looking at krill oil specifically, a meta-analysis published in 2017 found that people who supplemented with krill oil had significant reductions in LDL (or bad) cholesterol and triglycerides and higher levels of HDL (or good) cholesterol.
Although krill oil tends to contain lesser amounts of DHA and EPA than some fish oil supplements, it appears that krill oil provides similar benefits for heart health but at a lower dosage. The paper, published in Archives of Medical Science, compared high dosage pure omega-3 supplements (2,000 mg) with krill oil (1,000 mg) and found that, while both sources improved triglyceride plasma levels, pure omega-3 was more efficacious. However, only krill oil was capable of significantly improving HDL cholesterol levels.
5. Krill Oil Boosts Cognitive Function
Omega-3 fatty acids play an important role in brain health at every stage of life. From the womb to adulthood, obtaining omega-3 fats in the diet directly influences brain development, neuroplasticity, memory-related learning, and complex cortical processing. In older adults, omega-3 supplementation helps maintain cognitive function into old age.
Because the omega-3 fats in krill oil are derived from phospholipids, researchers investigated how it might impact the brain differently than omega-3 triglycerides. The 2013 study recruited 45 healthy men between the ages of 61 to 72 to receive either krill oil, sardine oil (which is rich in triglyceride omega-3 fats), or placebo for 12 weeks. While both krill and sardine oil supplementation showed improvements during memory and calculation tasks compared with placebo, krill oil activated cognitive functions more effectively than sardine oil.
Additionally, the antioxidant astaxanthin found in krill oil appears to have a neuroprotective effect on the brain by neutralizing free radical damage and oxidative stress associated with dementia and cognitive decline.
6. Krill Oil for the Management of Premenstrual Syndrome
Affecting 80% of women, premenstrual syndrome (PMS) is a collection of physical and emotional symptoms that occur 1 to 2 weeks prior to menstruation. While over 200 symptoms have been identified, the most common are abdominal pain, bloating, breast tenderness, depression, mood swings, fatigue, headaches, and difficulty sleeping. PMS may be caused by a combination of factors including hormone imbalance, increased inflammation, and chemical changes in the brain.
To evaluate the anti-inflammatory and analgesic effects of krill oil on the symptoms of PMS, 70 women diagnosed with PMS supplemented with either 2,000 mg of krill oil or omega-3 fish oil for 90 days in a 2003 study. Covering three menstrual cycles, the volunteers completed self-assessment questionnaires on day 1, day 45, and day 90. While both fish oil and krill oil had a similar effect on reducing abdominal pain, swelling, weight gain, and bloating, krill oil alone had a significant benefit for all emotional symptoms (depression, irritability, stress, feeling overwhelmed), as well as breast tenderness and joint pain.
Where To Buy Krill Oil
Although krill is considered one of the most abundant species on the planet with an estimated 420 million to 700 million metric tons of krill in the Antarctic ocean alone – we should still be careful to purchase brands of krill oil that are sustainably sourced – like this bottle by Spring Of Life.
While krill oil is generally safe and well tolerated with few side effects, supplementing with omega-3 fatty acids can increase the effects of blood thinning medications (like aspirin and warfarin) so speak with your doctor before taking krill oil or other types of fish oil. And since krill is technically a shellfish, people with shellfish allergies should not take krill oil.