Does Fish Oil Lower Cholesterol?

author avatar Dr. Eric Berg 02/11/2024

Fish oil is a rich source of heart-health-promoting fatty acids, but does fish oil lower cholesterol?

Evidence suggests that fish oil can help balance blood cholesterol in some people but has little to no effect in others. 

Discover the benefits of fish oils for cardiovascular health and learn why high cholesterol levels may result from eating carbs and sugars.  

Fish oil capsule with herring

What is fish oil?

Fish oil is extracted from oily fish by mechanically pressing their flesh or removing the oils using various chemical solvents.

The majority of fish oil is derived from fatty fish species such as mackerel, salmon, herring, or anchovies, and fish oil supplements have become one of the most popular dietary supplements in the U.S.

Fish oil contains high concentrations of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), two anti-inflammatory omega-3 fatty acids with impressive health benefits. 

EPA and DHA play a critical role in regulating various physiological functions. However, the body can’t produce these fatty acids and has to rely on dietary intake to maintain optimal EPA and DHA levels. 

Research published in Nutrition Journal found that most U.S. adults don’t meet their recommended oily fish intake, leaving many at risk of omega-3 deficiency, which is linked to an increased risk of cardiovascular disease, inflammation, and poor cognitive health.  

Watch the video below to learn how fish oils can help prevent heart disease. 

Understanding cholesterol 

The link between dietary habits, cholesterol levels, and heart disease risk is complex and often misunderstood.

Cholesterol is biologically important and plays a crucial role in cell membrane integrity, hormone synthesis, and vitamin D production, and a lack of adequate cholesterol can have serious health consequences.

Cholesterol isn’t water-soluble and requires specialized transport proteins that carry it through the blood. 

The two main cholesterol proteins are low-density lipoprotein (LDL cholesterol) and high-density lipoprotein (HDL cholesterol), and whether cholesterol increases the risk of cardiovascular disease depends on the type of lipoproteins it’s bound to.  


Certain types of LDL cholesterol, often referred to as bad cholesterol, can contribute to atherosclerosis, one of the leading risk factors for high blood pressure, stroke, and heart attacks.

HDL cholesterol, or good cholesterol, helps lower the risk of heart disease by removing excessive LDL cholesterol from the bloodstream.

It’s commonly believed that cholesterol-containing foods such as meat, dairy, seafood, and eggs raise cholesterol levels. However, a study published in Nutrients found that dietary cholesterol intake has no impact on blood cholesterol concentrations. 

In contrast, consuming foods with a high glycemic index, such as sugars and carbs, can significantly impact cholesterol balance by increasing LDL cholesterol levels while reducing HDL cholesterol. 

Research published in Current Atherosclerosis Reports confirms the effects of carbohydrates on cholesterol levels and concludes, “Dietary carbohydrates, particularly simple sugars and starches, can increase LDL and plasma triglyceride concentrations. Low-carbohydrate diets may have the opposite effects.” 

Cholesterol meter illustration

Can fish oil lower cholesterol?

While some research suggests that fish oil can be beneficial for lowering cholesterol, other studies fail to confirm the cholesterol-lowering effects of fish oil supplementation.

Cholesterol metabolism is complex and influenced by various factors such as dietary choices, lifestyle habits, overall health status, and genetics.

“A high-carb diet has been linked to elevated cholesterol levels,” says Dr. Berg. “However, many studies investigating the link between fish oil and cholesterol don’t consider the carbohydrate intake of the participants, which may partially explain the conflicting results.” 

Although EPA and DHA have been found to lower LDL and increase HDL cholesterol levels, their cholesterol-lowering properties may not be potent enough to overcome the detrimental effects of a high-carb diet on cholesterol balance.

Taking a fish oil supplement and following a nutritious low-carb diet like Healthy Keto® can promote balanced blood lipid levels and support a healthy body weight, associated with a lower risk of coronary heart disease, metabolic syndrome, and high blood pressure.  

Man biting on a fish oil capsule

4 benefits of fish oil

Maintaining adequate EPA and DHA intake has been associated with many benefits and may help lower the risk of serious health issues, including heart disease, inflammatory conditions, and even cancer.

Here are four benefits of fish oil.

1. Lowers the risk of heart disease 

Regardless of whether fish oil helps lower cholesterol levels, EPA and DHA have various other benefits for cardiovascular health.

A study published in Circulation found that fish oil supplementation is an effective therapeutic tool for lowering systolic and diastolic blood pressure, which can help manage or reverse hypertension, one of the leading cardiovascular risk factors associated with heart disease. 

In addition, EPA and DHA are natural blood thinners and help prevent blood clot formation, significantly lowering the risk of stroke and heart attacks.  

2. Helps reduce inflammation 

EPA and DHA are potent anti-inflammatory fatty acids, and taking fish oil can help lower chronic inflammation linked to cancer, cardiovascular disease, and cognitive decline. 

Evidence published in Journal of the American College of Nutrition found that fish oil supplementation is a potentially effective strategy to manage various inflammatory health issues, including Crohn’s disease, inflammatory bowel disease, psoriasis, and migraine headaches. 

3. Promotes cognitive health 

Omega-3 fatty acids play a critical role in maintaining brain function, and lack of adequate EPA and DHA intake can lead to neurological issues, cognitive decline, and mood disorders. 

EPA and DHA have been found to support neuronal function, enhance neurotransmitter production, and promote the exchange of oxygen and nutrients in brain cells, all of which help maintain a healthy central nervous system. 

4. May alleviate arthritis symptoms  

The body can convert EPA and DHA into anti-inflammatory compounds that help resolve inflammation, which may be especially beneficial for individuals with rheumatoid arthritis and osteoarthritis. 

A study published in Rheumatology confirms the anti-inflammatory effects of omega-3 fatty acids and suggests that fish oil supplementation can help alleviate arthritis symptoms, including joint pain, swelling, and stiffness. 

Krill and krill oil capsule

Other sources of omega-3 fatty acids

Certain types of marine algae are the primary sources of EPA and DHA for oily fish species, making algae oils and extracts an excellent alternative omega-3 source to fish oil, especially for vegetarians and vegans.

Krill oil is considered the best natural source of omega-3 fatty acids and contains EPA and DHA in phospholipid form, which is more readily absorbed into the body than the fatty acids in fish oil. 

Alpha-linoleic acid (ALA) is another type of omega-3 fatty acid that can be converted into EPA and DHA. However, conversion rates vary significantly amongst individuals, and it’s not recommended to rely on ALA intake to promote optimal EPA and DHA levels.

ALA has been found to promote brain and heart function, supports healthy vision, and plays a role in skin health. 

These foods are rich sources of ALA:

  • Flaxseed oil

  • Chia seeds

  • Walnuts

  • Hemp seed oil

  • Brussel sprouts

  • Green leafy vegetables 

Man reading a supplement label

Can you take fish oil if you have high cholesterol? 

Yes, you can take fish oil with elevated cholesterol levels.

While the effects of fish oil on cholesterol balance may vary, omega-3 fatty acids can help improve overall cardiovascular health by lowering blood pressure, decreasing inflammation, and improving blood vessel function.

However, it’s best to discuss the use of fish oil supplementation with a healthcare provider if you have imbalanced blood lipids to determine the appropriate dosage and arrange for regular blood tests to evaluate the impact of fish oil on your cholesterol levels.

Downsides of fish oil

Fish oil supplementation is generally considered safe and not associated with adverse side effects if taken in appropriate doses.

However, EPA and DHA are blood thinners, and taking fish oil supplements can increase the risk of excessive bleeding in individuals taking blood-thinning medication or those with bleeding disorders. 

In addition, fish oil has blood-pressure-lowering properties, and taking fish oil supplements can cause dangerously low blood pressure if combined with anti-hypertensive medications.  

In some cases, fish oil supplements can have an unpleasant fishy aftertaste or cause bad breath, and taking fish oil with food can help minimize these issues.   

Fish oil capsules in fish shape

Key takeaways

Fish oil has various impressive benefits for cardiovascular health, but does fish oil lower cholesterol? 

While fish oil has been shown to lower cholesterol in some individuals, it appears to have little to no effect in others, which may be related to genetic factors or a high-carb diet.

Although fish oil supplementation is generally considered safe, EPA and DHA are natural blood thinners and shouldn't be combined with blood-thinning medications to minimize the risk of excessive bleeding.  



1. Can fish oil lower cholesterol?

Yes, fish oil has been found to lower cholesterol in some people. 

However, there appears to be a subset of individuals that don’t benefit from fish oils’ cholesterol-lowering effects, which may be related to genetic factors or dietary habits such as a high-carb diet.  

2. Why is fish oil good for your heart?

Fish oil is a rich source of omega-3 fatty acids, which profoundly benefit heart health as they help reduce inflammation, promote healthy blood pressure, and improve blood vessel function.

In addition, omega-3 fatty acids may help lower cholesterol levels and prevent the formation of blood clots, which helps prevent strokes and heart attacks. 

3. What is the best type of fish oil?

The best type of fish oil contains between 250 and 500 milligrams of the omega-3 fatty acids eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA).

It’s best to opt for fish oil that has been purified, is free of heavy metals and other environmental pollutants, and has been tested and certified by a trusted organization such as the United States Pharmacopeia (USP). 

4. Should I take fish oil if I have high cholesterol?

Fish oil can help lower cholesterol in some individuals but may be less effective in others.

If you consider taking fish oil to promote balanced cholesterol levels, it’s crucial to consult a healthcare provider to determine the correct dosage and arrange for regular blood tests to evaluate the effects of fish oil on cholesterol levels.

5. What reduces cholesterol quickly?

The best way to reduce high cholesterol is to follow a nutritious, low-carb diet, consume plenty of heart-healthy omega-3 fats, and engage in regular physical activity.

In addition, certain supplements such as turmeric, red rice yeast, bile salts, and vitamin B3 can promote balanced blood lipid levels and reduce high cholesterol naturally.  

6. Who shouldn’t take fish oil?

Individuals with blood clotting disorders and those taking blood thinning medication shouldn’t take fish oil due to its blood thinning properties that can increase the risk of excessive bleeding.

Fish oil also has blood-pressure-lowering effects and can cause dangerously low blood pressure if combined with anti-hypertensive drugs. 








Healthy Keto Guide for Beginner

FREE Keto Diet Plan