Nowadays, consciousness toward high-quality marine food products and dietary supplements has increased. There is growing interest in finding alternative marine sources with similar nutritional profiles and health benefits as fish. In recent years, krill oil has become popular as a nutritional supplement. It contains nutrients such as fat-soluble vitamins A and E, minerals, omega-3 fatty acids (n-3 PUFAs), phospholipids, and active components such as astaxanthin and flavonoids.
Krill Oil: An Introduction
This oil gets extracted from Euphausia Superba, a small crustacean in the antarctic ocean. The visible external gills and luminous organs help in distinguishing it from shrimp. It usually lives in colder regions of the sea.
Krill is the largest biomass of zooplanktons found in the ocean. It makes up 50% of the zooplankton in the ocean food chain. It serves as a feed for marine animals such as whales, seals, squids, fishes, seabirds, and humans. They have a pinkish and reddish hue due to the plankton they eat. People of Japan, South Korea, and Taiwan have been harvesting krill as a human food source since the 19th century.
The HealthifyMe Note
Krill is the most abundant type of zooplankton in the ocean. It generally serves as a feed for marine animals. Because of the plankton they consume, krills have a pinkish and reddish colour. This oil contains fat-soluble vitamins A and E, minerals, omega-3 PUFAs, phospholipids, and active components like astaxanthin and flavonoids.
- It contains a perfect amount of omega-3 fatty acids. Both EPA and DHA naturally exist in krill oil as phospholipids. Phospholipids prevent the accumulation of fats in the river.
- This oil also contains astaxanthin, a fat-soluble carotenoid that possesses antioxidant properties. Astaxanthin usually has a dark reddish-orange colour. It contributes to a pinkish hue in the native krill.
- It contains alpha-tocopherol, known as vitamin E. Alpha-tocopherol exhibits excellent antioxidant properties.
- During the extraction of krill oil, folate and vitamin B12 get lost.
- This oil shows metabolic, anti-inflammatory, neuroprotective, and chemopreventive activities.
Krill oil is available in soft gel supplements. The U.S. Food and Drug Administration has no specific recommendations on the safety or effectiveness of this oil. It is considered a dietary supplement, and one does not need a prescription to use it. The adequate dosage of krill oil gets determined by the amount of DHA and EPA omega-3 fatty acids in the supplement. Furthermore, the FDA recommends no more than 2 g of EPA and DHA daily.
Helps Lower Blood Lipid Profiles
Krill oil contains omega-3 polyunsaturated fatty acids such as DHA (Docosahexaenoic acid) and EPA (Eicosapentaenoic acid). These fatty acids effectively reduce triglyceride levels and inflammatory symptoms associated with heart disorders.
In a study of 129 subjects, researchers administered krill oil and fish oil for 7-weeks to investigate their effects on the plasma levels of EPA and DHA, serum lipids, biomarkers of inflammation, oxidation stress, and hemostasis. The subjects were healthy volunteers with normal or slightly elevated blood cholesterol and triglyceride levels. At the end of this study, plasma levels of DHA, EPA, and DPA increased in the subject group supplemented with fish oil and krill oil. No significant changes in lipid profile were there for those who had fish oil. Still, there was a notable increase in HDL cholesterol(good cholesterol) and reduced triglyceride levels in the krill oil group.
A 3-month randomised study conducted to assess krill oil’s effects on cholesterol found that it reduced the total cholesterol, LDL, and triglycerides levels while improving HDL levels. The results demonstrated that krill oil is an effective oil treatment for hyperlipidemia management. At equal or low doses, krill oil was more effective than fish oil in reducing glucose, triglycerides, and LDL levels.
The effects of omega-3 fatty acids in cardiovascular diseases are evident. It is cardioprotective and has preventive effects against cardiovascular diseases. It lowers blood pressure and triglyceride levels, the two major risk factors in cardiovascular diseases.
In a randomised controlled trial, researchers evaluated the effect of krill oil on cardiovascular disease risk factors and blood glucose control in type-2 diabetes patients. The results of this trial show that krill oil may increase HDL levels and lead to moderate improvement of cardiovascular risks and type-2 diabetes.
A study assessing krill oil’s effects on vascular inflammation and atherosclerosis had positive results. Atherosclerosis is a chronic inflammatory disease leading to stroke, heart attack, and peripheral arterial disease. Krill oil inhibits vascular inflammation. It stops plaque formation in the carotid artery by preventing the buildup of fats, cholesterol, and other substances in the artery walls.
In a study, researchers advised that one should take an adequate amount of the essential fatty acids from dietary sources rather than supplements.
Antioxidant and Anti-inflammatory Properties
Krill oil contains a high amount of vitamin E and has potent antioxidant properties. Antioxidants prevent oxidative damage by neutralising the effect of free radicals. It contains astaxanthin, a natural antioxidant, vitamin A, and omega-3 fatty acids, which show anti-inflammatory and antioxidant activities. Krill oil possesses anti-inflammatory properties due to the presence of DHA and EPA.
A study suggests that consuming krill oil and diet supplementation notably reduced arthritic scores and hind paw swelling in animals. Krill oil also reduced the symptoms of inflammatory arthritis. Studies have proven that omega-3 and omega-6 fatty acids and antioxidants in marine foods prevent the progression of neurodegenerative diseases. Studies show that astaxanthin present in krill oil can directly cross the blood-brain barrier. Astaxanthin, along with omega 3, improves the cognitive benefits and alleviates inflammation. It reduces the progression of neurodegenerative diseases such as Alzheimer’s and prevents cognitive loss.
The HealthifyMe Note
Krill oil regulates lipid metabolism, inflammation, and oxidative stress. The presence of high levels of vitamin A, alpha-tocopherol, and astaxanthin in krill oil makes it superior to fish oil in terms of biological effects. These components in krill oil make it stable and resistant to oxidation.
Krill Oil Vs Fish Oil
Since krill is also a fish, many people feel that krill oil and fish oil are similar. However, there are a number of differences between the two.
- Fish oil is obtained from tissues of cold-water oily fish such as salmon, herrings, sardines, anchovies, and mackerel. Krill oil gets obtained from antarctic krill, i.e., a small shrimp-like crustacean.
- Fish oil supplements are usually yellowish-gold in colour. Krill oil supplements are reddish due to astaxanthin, a naturally occurring antioxidant in krill oil.
- Fish oil has a higher concentration of DHA and EPA than krill oil. A study conducted to determine the bioavailability of krill oil and fish oil found that DHA and EPA from krill oil have higher bioavailability than in fish oil. Another study shows that krill oil is absorbed better than fish oil.
- Krill oil contains astaxanthin, an antioxidant. The differences between krill oil and fish oil may be due to phospholipids in krill oil and triglycerides in fish oil.
- Fish oil is unstable and highly susceptible to oxidation which further degrades the quality of the oil. Krill oil is rich in antioxidants such as astaxanthin and tocopherol, which protect the oil from oxidation and prevent it from getting rancid. The presence of antioxidants present in krill oil makes it more stable than fish oil. Krill also doesn’t have a fishy smell or aftertaste.
- There are concerns regarding the high mercury concentration and other toxins in fish. Krill oil does not have high levels of mercury and other contaminants or toxins because it comes from the bottom level of the ocean food chain.
Potential Side Effects
There is not adequate research to determine the possible side effects of krill oil. It is a dietary supplement and is reasonably safe when used for a short period in recommended doses. However, krill oil might have similar side effects as fish oil. If taken in high doses, krill oil can increase blood clotting time.
Other side effects are as follows:
- Loose stools
- Bad breath
- Upset stomach
- Acid reflux
- Suppressed appetite
- Chest pain
- Body ache
- Back pain
- Mild skin rash
Precautions and Safety Tips
Even though krill oil is a fairly safe dietary supplement, there are certain circumstances when you should avoid it. Specific conditions when one should avoid this oil are as follows
People with seafood allergies such as shellfish or shrimp should avoid eating krill oil.
Excess Consumption can be Harmful.
Do not take an excessive dose of this oil or for an extended period. Consume krill oil as directed on the label or the amount doctor prescribed for a specific condition. Excess consumption can cause weight gain, increase blood sugar levels, and increase the risk of bleeding.
Avoid it Pre and Post-Surgery.
People having surgery should stop using krill oil at least 2-weeks before the procedure. It is advised so because krill oil can slow down the blood clotting process. It can increase the risk of bleeding during and after the surgery.
Pregnancy and Lactation Care
There is no authentic information on whether krill oil is safe during pregnancy and breastfeeding. Hence, it’s better to be safe and avoid krill oil during the period. You should tell your doctor if you’re using krill oil while trying to conceive, pregnant, or lactating.
People with bleeding disorders such as coagulopathy or haemophilia should avoid using krill oil because it slows blood clotting. It increases the risk of bleeding out in people.
Anticoagulant or Antiplatelet Drugs
People taking anticoagulant or antiplatelet medicines should avoid using krill oil because it can slow down blood clotting. It can increase the risk of bleeding and bruising in them. It is advised to inform the physician before taking krill oil dietary supplements.
Consult a healthcare provider before taking this supplement if you suffer from diabetes, liver and pancreas disorders, blood clotting disorders, and underactive thyroid conditions. People taking estrogens, blood thinners, NSAIDs, beta-blockers, diuretics, or weight loss pills should inform the doctor before taking krill oil supplements. These drugs may interact with krill oil.
People who are taking antidiabetic drugs should avoid krill oil. Krill oil with antidiabetic drugs can drop blood sugar levels to a dangerously low level.
Krill oil is a relatively safe dietary supplement based on nutrient composition. It is a rich source of highly bioavailable omega-3 PUFAs and antioxidants such as astaxanthin. It is known for various health benefits such as reducing lipid levels, cardioprotective activities, neuroprotective properties, antioxidant activities, anti-inflammatory properties, and chemopreventive effects. While it has multiple health benefits, the research related to them is inadequate.
It concerns that research regarding krill oil’s health benefits, side effects, and nutritional profile is not satisfactory enough to achieve a suitable result. There’s a need for more research trials and studies to conclude to know how krill oil affects human health.
Frequently Asked Questions
Q. What does krill oil do for your body?
A. Krill oil is an excellent source of healthy fats. It contains omega-3 fatty acid that prevents the progression of cardiovascular diseases such as heart strokes and attacks. It reduces triglycerides and LDL cholesterol levels in the blood and improves blood circulation in the body. It also helps to lower blood pressure and prevent hypertensive conditions. It helps to fight inflammation and relieve arthritis and joint pain.
Q. Can I take krill oil every day?
A. Yes, you can take krill oil every day. Consult a physician about the recommended dose of krill oil and how long you can take it based on your condition. The recommended dose of krill oil is determined based on the DHA and EPA amount found in supplements. Recommended combined daily dose of DHA and EPA is between 250-500 mg.
Q. Who should not take krill oil?
People allergic to seafood such as shellfish and fish should avoid using krill oil. People who have surgery should stop using krill oil at least 2-weeks before surgery. It is advised because krill oil can slow blood clotting. It increases the risk of bleeding during and after the surgery. Pregnant or lactating mothers should also avoid krill oil due to the lack of evidence on how it may affect them or the baby.
Q. Do doctors recommend krill oil?
A. Yes, doctors do recommend krill oil as a dietary supplement. It is because of its preventive properties against cardiovascular diseases. Omega-3 fatty acids in the krill oil help delay the progression of symptoms associated with coronary heart and cardiovascular diseases. According to U.S. Food and Drug Administration, krill oil is a dietary supplement and does not require a prescription.
Q. Does krill oil make you gain weight?
A. Krill oil contains omega-3 fatty acids that are highly recommended for individuals wishing to lose body fat. It aids in weight management by reducing fat storage in the body. However, excess consumption of krill oil might make you gain weight. It is simply because krill oil is rich in fat and has high calories. Too much consumption of krill oil may increase one’s metabolic weight.
Q. Does krill oil help hair growth?
A. Yes, omega-3 fatty acids present in krill oil are very effective in fighting dry scalp and keeping the hair follicles strong. Healthy fats such as omega-3 fatty acids help with cell regrowth which is beneficial in preventing hair loss and hair damage. It nourishes the itchy scalp and reduces dandruff by regulating oil production on the scalp. It prevents premature greying of hair, improves the hair growth cycle over time, and improves hair density.
Q. Does krill oil clear arteries?
A. Yes, krill oil helps to remove plaque in the heart arteries. It reduces the growth rate of plaque that clogs blood vessels. Omega-3 fatty acids present in krill oil reduce the triglycerides levels as well as LDL cholesterol levels. It prevents the inflammation of blood vessels and the formation of blood clots which may block the arteries entirely.
Q. Can you take krill oil and vitamin D together?
A. Vitamin D is best absorbed when taken with meals that contain fats or oils. Krill oil is also rich in fat-soluble vitamins such as A, D, and E and omega-3 fatty acids such as DHA and EPA. However, there are no known interactions between omega-3 fatty acids and vitamin D3. So, it is safe to consume krill oil and vitamin D together. However, it is necessary to consult a doctor before consuming them together.
Q. Is krill oil good for your skin?
A. Yes. Krill oil contains omega-3 phospholipids, which benefit skin health. It contains astaxanthin which exhibits photoprotective properties and fights against the degenerative effects of sun damage. It reduces the appearance of fine lines, wrinkles, and hyperpigmentation. Krill oil also promotes cell regeneration which helps smoothens the skin texture and improves skin elasticity.
Q. Can krill oil raise blood pressure?
A. No, krill oil contains omega-3 fatty acids, which help reduce blood pressure. If the person is allergic to krill oil, they should avoid eating it as it increases bleeding risk, lowers blood pressure, and may impact blood sugar levels. But it certainly won’t raise blood pressure.