The oil that strengthens your body by reducing fat, inflammation, and cellular stress

HISTORY IN BRIEF

• Krill oil reduced liver fat, deep abdominal fat, and triglyceride levels in obese mice, demonstrating that it helps reverse key factors in fatty liver disease.
• Krill oil reduced oxidative stress and activated natural antioxidant enzymes, helping cells protect themselves from damage caused by fat overload.
• Krill oil improved insulin sensitivity because it reduced insulin levels and increased adiponectin, a hormone that helps the body burn fat and use sugar properly.
• The omega-3s in krill oil differ from those in fish oil because they are bound to phospholipids, making them easier to absorb and more effective at fighting inflammation and fat accumulation.
• Krill oil outperformed a prescription cholesterol drug on several important markers and did so without producing side effects, making it a safer way to restore metabolic health.

By Dr. Mercola

Fatty liver disease is one of the earliest, and most overlooked, signs that your metabolism is malfunctioning. It often appears without warning, damages the liver without you even realizing it, and sets the stage for insulin resistance, obesity, and heart disease. Yet, most people don’t realize they have it until it’s in an advanced stage. But it’s not all bad news. Recent research has uncovered targeted, natural solutions that can help reverse this trend. One of the most promising solutions is krill oil, a source of omega-3 fatty acids that many people are deficient in.

Krill oil not only masks symptoms but also helps restore the biological factors that promote fat accumulation, inflammation, and oxidative stress at their source. Discover how this marine oil, unlike standard fish oil, helps protect the liver, optimizes cholesterol metabolism, and supports antioxidant defenses.

Krill oil fights fat, inflammation, and oxidative stress all at the same time

A 2024 study published in  Nutrients  examined the effects of krill oil supplementation in mice with diet-induced obesity and metabolic dysfunction.^¹  The aim was to see if krill oil could reduce fat accumulation in the liver, optimize cholesterol levels, and decrease oxidative stress—all important factors in fatty liver disease and cardiovascular risk. The researchers also analyzed whether compounds in krill oil interfere with specific enzymes that promote cholesterol synthesis and fat storage.

The animals used in the study were fed a high-fat diet to simulate obesity and metabolic damage:  the mouse model was designed to reflect what happens in humans who consume high-fat, high-calorie foods. These animals gained weight, accumulated visceral and liver fat, and developed blood markers associated with poor metabolic health.

Krill oil was administered at a dose of 400 milligrams (mg) per kilogram (kg) daily for 60 days. Researchers tracked changes in blood cholesterol levels, triglyceride levels, liver enzyme levels, and markers of oxidative stress to assess the effects of krill oil.

• Krill oil reduced liver fat and total triglyceride levels in a dose-dependent manner:  Mice given krill oil experienced a significant reduction in liver fat storage, with decreases in both liver weight and deep abdominal fat, similar to visceral fat in humans. Intracellular triglyceride levels also decreased when krill oil was added to the diet. Liver triglycerides decreased from 0.73 mg/dL in obese mice to 0.59 mg/dL after krill oil supplementation. This suggests that krill oil either directly reduces fat production or increases fat breakdown in the liver.

• Krill oil significantly reduced oxidative stress within liver cells:  Researchers analyzed the symptoms of cell damage caused by the breakdown of fats. Mice fed a high-fat diet had elevated levels of this damage, but krill oil helped reduce it. Krill oil also stimulates the body’s natural defense systems, such as enzymes that help break down harmful substances and protect cells.

• Krill oil improved insulin sensitivity in obese mice:  Insulin resistance was measured using the HOMA-IR test, one of the most reliable ways to assess how well the body handles insulin. A low score reflects good insulin sensitivity.

Krill oil significantly reduced this score, along with serum insulin levels, demonstrating that it helped the body respond better to insulin and process glucose more effectively. Adiponectin levels also increased (this hormone promotes insulin sensitivity and fat metabolism). On the other hand, leptin, which promotes fat storage, decreased.

The strongest effects came from how krill oil modified important enzymes and proteins:  krill oil had its greatest impact on changing the function of certain enzymes and proteins in the body. This oil reduced the activity of the main enzyme the liver uses to produce cholesterol, the same enzyme targeted by statin medications, but without the side effects. Krill oil also reduced a protein that signals the body to produce more fat.

The omega-3 fatty acids in krill oil are more bioavailable than those in fish oil.

Unlike fish oil, which carries omega-3s bound to triglycerides, krill oil binds eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) to phospholipids, the fat molecules that form the outer layer of cells. This makes it easier for cells to absorb and integrate them into their membranes. Therefore, although krill oil contains less EPA and DHA than fish oil by volume, it delivers more of them to the body where they are truly needed ^.

Krill oil also contains astaxanthin, a powerful antioxidant that resists rancidity.  Astaxanthin not only gives krill oil its deep red color, but it also has a significant protective effect. The structure of astaxanthin makes krill oil much more stable and resistant to oxidation than standard fish oil, which easily becomes rancid.

Krill oil matched or outperformed a lipid-lowering drug:  Researchers compared krill oil to fenofibrate, a drug used to lower cholesterol. ³  On many important markers, including LDL cholesterol, liver triglycerides, and antioxidant status, krill oil performed as well as or better, without producing the side effects seen with drugs like fenofibrate.

• Krill oil helped restore balance in multiple systems at once:  What’s most impressive is that krill oil didn’t just address one problem, but also improved fat metabolism, cholesterol management, oxidative stress, and inflammatory signaling. This kind of multi-targeted action is highly beneficial. This makes krill oil ideal for people suffering from metabolic dysfunctions, fatty liver, or insulin resistance.

How to reverse fatty liver and metabolic damage naturally

If you have symptoms of fatty liver, weight gain, or blood sugar problems, it’s not just a matter of eating less or exercising more. These are signs that your metabolism is under stress, and the solution begins with restoring balance at the cellular level.

Fat accumulation in the liver, along with insulin resistance and inflammation, doesn’t happen quickly; it’s the result of mitochondrial dysfunction, poor fat metabolism, and oxidative damage. But there are steps you can take today to change that.

1. Add krill oil to your daily routine. It works differently than fish oil:  if you take fish oil, consider replacing it with krill oil. Unlike fish oil, krill oil binds omega-3s like EPA and DHA to phospholipids, the same type of fat that makes up cell membranes. This means your body absorbs it better where it needs it most—in the liver and cells. In the study, krill oil reduced liver fat, improved insulin sensitivity, and reduced oxidative stress in just 60 days. ⁴

2. Eat more foods that support fat metabolism, especially fatty fish:  If you prefer food-based sources, prioritize wild-caught fish such as Alaskan salmon, sardines, anchovies, and mackerel. These are rich in omega-3 fatty acids and low in contaminants. Obtaining omega-3s from food gives your body the tools to control inflammation and support fat processing, particularly in the liver.

3. Avoid low-quality omega-3 supplements that do more harm than good:  Most fish oils on the market are prone to oxidation, meaning they easily become rancid, especially if stored improperly. Rancid oils produce harmful compounds that promote inflammation rather than reduce it. Krill oil is naturally protected by astaxanthin, an antioxidant that prevents it from breaking down and becoming toxic.

However, keep in mind the omega-3 paradox, where more isn’t always better. High doses, especially those from supplements, have been linked to an increased risk of atrial fibrillation, a serious heart rhythm problem.^⁵ You don’t need very high doses to reap the benefits. Whenever possible, take a food-first approach and moderate your krill oil supplement intake—just enough to support liver repair and heart health, but without overdoing it.

4. Eliminate vegetable oils to balance your fat intake:  If you frequently consume processed foods made with soybean oil, canola oil, corn oil, or sunflower oil, you flood your body with linoleic acid (LA), which worsens inflammation and negates the benefits of omega-3s. Replace these oils with healthier options like tallow, ghee, and butter from grass-fed animals, and get your omega-3s from good-quality sources like krill oil or fatty fish.

5. Boost your body’s natural antioxidant defenses:  Oxidative stress has a significant impact on liver damage and insulin resistance. Krill oil not only reduces damage but also helps activate the body’s antioxidant systems, including powerful enzymes that cleanse within cells and break down harmful substances before they cause problems. To further support this process, consume antioxidant-rich foods such as berries, herbs, and colorful vegetables.

If you’re struggling with belly fat, low energy, or increasingly high blood sugar levels, these aren’t random symptoms—they’re actually connected. Krill oil is a simple, science-backed tool that helps address the root causes, not just the symptoms. Use it as part of a broader lifestyle change that nourishes your body instead of overwhelming it.