Krill Oil is Taking the Nutritional World by Storm. Top MD Explains Why You Need it

By now you've heard all about the many benefits of omega-3 fatty acids and you know that seafood is a good source of these healthy fats. You also know you can get your omega-3s in supplement form. But if you head to a health-food store or turn down the supplement aisle at your local drugstore to pick up a bottle of omega-3s, you'll see it's far more complicated than it may seem at first. There are a number of types of omega-3s available in supplement form, including fish oil, krill oil, cod liver oil and algal oil (a vegetarian source of omega-3s derived from algae). Of these, krill oil and fish oil are the ones most of us are familiar with. But which one is better for you? Read on to see which one wins the battle of krill oil vs fish oil.

What is krill oil?

Krill oil is a nutritional supplement made from Antarctic krill — small shrimplike crustaceans that are a major food source for whales, seals and penguins.

What makes krill oil healthy?

Krill oil, like fish oil, contains lots of omega-3 fatty acids, including EPA (eicosapentaenoic acid) and DHA (docosahexaenoic acid). However, the omega-3s in krill oil have a different shape, which affects the way your body uses them.

“Traditional fish oil supplements provide omega-3s as triglycerides, while krill oil provides them as phospholipids,” explains Sonali Ruder, DO, a board-certified emergency-room doctor, chef and the founder of the Foodie Physician. “Phospholipids may be absorbed better by the body. But this is something that is still being researched and more studies are needed.”

Carmelita Lombera, RD, a registered dietitian and nutritionist, agrees. “Our cell membranes are made up of a phospholipid layer, so they absorb krill oil better than fish oil. One study even showed that krill oil provides the same benefits as fish oil but at a lower dosage.” That means you can save money with krill oil!

In another study, published in the journal Lipids in Health and Disease, researchers found that the omega-3s in krill oil last longer in the body than those found in fish oil.

Why is everyone talking about krill oil?

Over the last five years or so, krill oil has become increasingly popular. But why is that? Scientists point to its low environmental impact.

“Krill oil is a more sustainable product than fish oil,” Lombera explains. “One report found that krill oil is more abundant than fish oil and is one of the most sustainably managed industries in the world.

Krill oil also contains lower levels of mercury and other heavy metals compared to fish oil.

“Since krill consume algae, they don’t accumulate high levels of toxins,” Lombera adds. “And most krill oil is harvested in the Southern (or Antarctic) Ocean, which is considered one of the cleanest and most pristine environments in the world.

Choose krill oil if you want these benefits:

Now that you know where krill oil comes from and what makes it unique, let’s take a closer look at its health benefits:

Reduced risk of heart disease

Many studies have shown a link between omega-3 fatty acids and a reduced risk of heart disease. “Omega-3s have also been shown to help maintain healthy levels of HDL, or “good,” cholesterol,” Dr. Ruder says.

And while research shows that fish oil can decrease triglycerides, reduce high blood pressure and prevent plaque from forming in the arteries, krill oil may have a leg up, as it contains the powerful antioxidant astaxanthin. Astaxanthin reduces cardiovascular inflammation and may even lower triglycerides and improve HDL or 'good' cholesterol. (That's not all astaxanthin does — click to see how astaxanthin helped one woman reverse thinning hair!)

Another study found that both krill oil and fish oil reduced heart disease risk factors. But krill oil was better than fish oil at lowering triglycerides, blood sugar, and LDL or 'bad' cholesterol.

Relief from premenstrual syndrome (PMS)

A study published in Alternative Medicine Review found that krill oil relieved painful abdominal cramps and mood swings. The researchers ultimately concluded that krill oil was more effective at managing PMS symptoms than fish oil.

Better brain function

“The omega-3 fatty acids in krill oil are important for brain health and may play a role in supporting cognitive function and memory,” says Dr. Ruder.

One study, published in the journal Clinical Interventions in Aging, found that 45 seniors who took a krill oil supplement for 12 weeks had improved brain oxygen levels (a factor that's been linked to better memory) and other measures of brain function. Scientists concluded that krill oil has "the potential to bring about more beneficial effects on cognitive function.”

In another study, krill oil was shown to boost brain levels of EPA and DHA; fish oil had no effect.

Less arthritis pain

Krill oil’s anti-inflammatory benefits may extend beyond the brain and heart. One study found that taking 300 milligrams of krill oil daily lowered inflammation and relieved stiffness and joint pain.

In another study of 50 adults with mild knee pain, participants reported a significant reduction in pain during sleep and activity after 30 days, as well as an increased range of motion.

Choose fish oil if you want these benefits:

Fish oil might not be as sustainable as krill oil, but it still offers a variety of health benefits. That’s particularly true if you’re trying to achieve specific outcomes, like smoother skin, stronger bones or a sunnier mood. Let’s take a closer look at the research:

Smoother, younger-looking skin

The omega-3s in fish oil are thought to boost skin health by improving hydration and regulating the production of oils. They also help moisturize dry skin and reduce irritation caused by psoriasis and dermatitis. And one study found that fish oil can help eliminate dry skin, ward off skin cancer and speed wound healing.

Improved mood

Women are more than twice as likely to suffer from depression as men. And several studies have found that people with depression tend to have lower levels of omega-3 fatty acids in their blood.

The good news? Scientists who tested fish oil for its effects on depression have found promising results: One meta-analysis found that fish oil supplements with 60% or higher EPA content helped relieve depression. That's where it may beat out krill oil, as another study found that subjects who supplemented with krill oil didn't experience a reduction in depressive feelings after one year.

Can I take krill oil and fish oil together?

If you want to get all of the benefits listed above, it’s perfectly safe to take both krill oil and fish oil supplements — as long as you space the dosages out.

“I recommend taking fish oil in the morning,” says Lombera. “Some people find that krill oil causes stomach issues, so taking it at night might be a better option. Also, pay attention to the dosage. Taking more than 2,000 milligrams of DHA and EPA daily increases the risk of side effects, like gas and diarrhea.”

Aside from taking krill oil and fish oil at different times, always take your fish oil supplements with a snack or small meal. Lombera says taking the supplement with food helps your body better absorb fat-soluble vitamins, like A, D, E, and K.

“Some people experience fishy belching after taking fish oil supplements with a large meal,” Lombera adds. “So you might want to try having smaller meals. I also recommend storing your krill oil and fish oil supplements in a cool, dark place like a pantry or refrigerator to reduce the fishy odor and side effects.”

Are krill oil and fish oil safe for everyone?

Krill and fish oil are considered safe and present few risks, but they aren’t for everyone.

For example, if you have a blood disorder or take blood-thinning medication, talk with your doctor before taking these supplements. Fish and krill oil can increase the risk of blood clots.

Likewise, you should talk to your doctor if you have fish or shellfish allergies. She can make supplement recommendations that align with your needs.

How much krill oil or fish oil should I take?

The dosage of krill oil you should take depends on several factors, including your age, health, and aims.

The National Institutes of Health (NIH) recommends consuming 1.1 to 1.6 grams of omega-3 fatty acids daily, or a minimum of 250 to 500 milligrams of combined EPA and DHA daily. This can be obtained by eating about 8 ounces of fatty fish per week or by taking a fish or krill oil supplement.

“Starting small can help you determine the proper dosage for your body,” Lombera says. “You can begin with 800 mg of krill oil per day for the first few weeks and then increase to 1,200 mg per day for maintenance.”

If you have underlying health conditions, talk to your doctor to find out the best dosage for you, as these factors may determine how much krill oil you can take.

“For example, people with heart disease may need 1,000 mg per day, whereas people with high triglycerides may need 2,000-3,000 mg until their levels are normal,” Lombera explains.

“People with depression can benefit from higher doses –– up to 2,000 mg per day. For those suffering from inflammation and joint pain, as little as 300 mg of krill oil can provide benefits.”

What should I consider when buying krill oil or fish oil supplements?

With so many krill oil and fish oil supplements available, choosing the right one can be challenging. Dr. Ruder recommends doing your research and buying a high-quality product from a reputable source.

“There are a lot of good options out there," says Dr. Ruder. "I personally like Life Extension. They sell omega-3 products made from fish (like fish and krill oil) as well as plant-based omega-3 supplements for those who can’t or don’t eat fish. Their supplements are high-quality and contain a high amount of omega-3s per serving.”

Is krill oil or fish oil better?

“Both krill and fish oil are excellent sources of omega-3s, but fish oil tends to be less expensive and more accessible than krill oil,” Dr. Ruder says. So if budget is your main concern, fish oil will save you some money.

However, if you’re concerned about your environmental footprint or want to address some of the health problems mentioned above (like relief from PMS, for example) krill oil might be the better option.

Interested in other supplements? Check out these articles!

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This content is not a substitute for professional medical advice or diagnosis. Always consult your physician before pursuing any treatment plan.