Garlic vs. Fish Oil: Which is Better for Your Health?

October 5, 2025 •

4 min read

According to the World Health Organization, cardiovascular diseases are the leading cause of death globally. Both garlic and fish oil have long been studied for their potential to support heart health and reduce inflammation, but the question remains: which is better, garlic or fish oil?

Quick Summary

This article compares garlic and fish oil based on their primary active compounds, health benefits, and specific effects on cardiovascular markers like cholesterol and triglycerides. It breaks down the key differences to help you decide which supplement aligns best with your wellness goals.

Key Points

Targeted Benefits: Fish oil primarily targets high triglycerides, while garlic is more effective at lowering total and LDL cholesterol.
Mechanism of Action: Fish oil's benefits come from omega-3 fatty acids (EPA and DHA), whereas garlic's come from sulfur compounds like allicin.
Blood Pressure and Inflammation: Both supplements offer benefits for blood pressure reduction and provide anti-inflammatory effects.
Potential for Combination: For certain health concerns, particularly broad cardiovascular support, combining garlic and fish oil may offer synergistic effects.
Interaction with Medications: It is crucial to consult a doctor before combining supplements, as both can have blood-thinning properties that may interact with anticoagulant medications.
Consider Side Effects: Garlic can cause bad breath and upset stomach, while fish oil can lead to a fishy aftertaste and digestive issues.
Informed Choice: Your best choice depends on your specific health goals and which risk factors you need to address most effectively.

Comparing Garlic and Fish Oil: A Deep Dive into Key Differences

When it comes to natural supplements for cardiovascular health, garlic and fish oil are two of the most popular contenders. Each boasts a long history of traditional use and is backed by scientific studies for its unique health properties. However, their mechanisms of action and primary targets within the body differ significantly, meaning one may be better suited for specific health concerns than the other. Understanding these differences is key to making an informed choice about your supplementation strategy. While fish oil is known for its omega-3 fatty acids, EPA and DHA, garlic's primary bioactive compound is allicin, a sulfur-based antioxidant.

The Health Benefits of Garlic

Garlic's benefits are largely attributed to its sulfur compounds, most notably allicin, which is released when the clove is crushed or chopped.

Blood Pressure Regulation: Research has consistently shown that garlic supplementation can lead to a significant reduction in blood pressure in individuals with hypertension. It helps relax blood vessels and promotes smoother blood flow.
Cholesterol Management: Studies indicate that garlic can modestly reduce total and LDL ("bad") cholesterol levels, though its effect on HDL ("good") cholesterol is less pronounced.
Antioxidant and Anti-inflammatory Properties: The antioxidants in garlic help protect the body's cells from oxidative stress and reduce inflammation. Aged garlic extract (AGE) is particularly rich in stable bioavailable antioxidants.
Immune Support: With natural antimicrobial, antiviral, and antifungal properties, garlic has long been used to support the immune system and help fight off infections.

The Health Benefits of Fish Oil

Fish oil is a rich source of the essential omega-3 fatty acids eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), which the body cannot produce on its own.

Triglyceride Reduction: One of fish oil's most well-documented benefits is its ability to significantly reduce high triglyceride levels.
Cardiovascular Support: Omega-3s help reduce inflammation, lower blood pressure, and slow the development of arterial plaque. They also help prevent the blood from clotting too easily.
Brain and Eye Health: DHA is a crucial component of the brain and retina, and omega-3s are associated with cognitive function and eye health.
Joint and Mental Health: Fish oil has anti-inflammatory properties that can help manage symptoms of rheumatoid arthritis. Some research also suggests a link between omega-3 intake and reduced symptoms of anxiety and depression.

Comparison Table: Garlic vs. Fish Oil

To help clarify the core differences, here is a detailed comparison of garlic and fish oil based on their primary benefits and mechanisms.


Feature	Garlic (Allicin)	Fish Oil (Omega-3s)
Primary Bioactive	Allicin and other sulfur compounds	EPA (eicosapentaenoic acid) and DHA (docosahexaenoic acid)
Main Target	Cholesterol metabolism, blood pressure regulation	Triglyceride reduction, inflammation control
Cholesterol	Can lower total and LDL cholesterol levels.	Does not reliably lower LDL; can sometimes raise it slightly.
Triglycerides	Minimal direct impact; primarily affects cholesterol.	Significantly and reliably reduces high triglyceride levels.
Blood Pressure	Modest reductions in both systolic and diastolic pressure.	Slight reduction, most notable in individuals with high blood pressure.
Anti-inflammatory	Contains general anti-inflammatory antioxidants.	Contains potent omega-3s that are known anti-inflammatory agents.
Side Effects	Bad breath/body odor, stomach upset.	Fishy aftertaste, digestive issues, potential bleeding risk.

Can you take garlic and fish oil together?

For some health objectives, particularly heart health, combining garlic and fish oil may offer synergistic benefits. A 1997 study found that a combination of garlic and fish oil had a more pronounced beneficial effect on serum lipid levels than either supplement alone, by combining garlic's cholesterol-lowering effects with fish oil's triglyceride-lowering capabilities. For example, the garlic can help counteract the modest increase in LDL cholesterol that fish oil can sometimes cause. However, it is crucial to consult a healthcare provider before combining supplements, especially because both can have blood-thinning effects, which is a concern for those on anticoagulant medications.

How to choose the right supplement for you

The right choice between garlic and fish oil depends on your specific health concerns and goals. If your primary issue is managing high cholesterol, garlic may offer a more direct benefit. For those with high triglycerides, fish oil is the clear winner. If you are looking for broad cardiovascular protection that addresses multiple risk factors, a combination may be most effective, but always under medical supervision. Furthermore, consider potential side effects and interactions. Individuals who experience gastrointestinal discomfort from garlic might prefer fish oil, while those bothered by the fishy aftertaste of omega-3 supplements might lean towards garlic.

Conclusion: Which is the winner?

There is no single winner between garlic and fish oil, as their strengths lie in different areas. The best supplement depends on your individual needs. Garlic is a powerful antioxidant with proven effects on blood pressure and cholesterol, while fish oil excels at lowering triglycerides and providing potent anti-inflammatory benefits. For comprehensive heart health support, combining them may offer the most robust benefits, but this should be discussed with a doctor to avoid contraindications, particularly if you take other medications or have a history of bleeding disorders.

For High Triglycerides: Choose fish oil.
For High Cholesterol: Choose garlic.
For Both: Consider taking them together under medical guidance.
For Anti-inflammatory Effects: Both are beneficial, but fish oil's omega-3s are particularly powerful.

Ultimately, a healthy diet, regular exercise, and consultation with a healthcare professional are the most effective strategies for maintaining optimal cardiovascular health. Supplements should be viewed as an aid to, not a replacement for, these fundamental healthy habits.

Frequently Asked Questions

Yes, many studies show that taking garlic and fish oil together can be beneficial for cardiovascular health, as they address different risk factors. However, you should consult a doctor before combining them, especially if you are taking blood-thinning medication, as both have blood-thinning properties.

Garlic has been shown to be more effective at lowering total and LDL ("bad") cholesterol levels than fish oil. Fish oil's main impact on lipids is reducing triglycerides, not cholesterol.

Fish oil, specifically its omega-3 fatty acids EPA and DHA, is significantly more effective at reducing high triglyceride levels than garlic.

Aged garlic extract (AGE) undergoes a process that converts the unstable allicin into stable, bioavailable compounds. This can result in a more potent antioxidant and anti-inflammatory effect compared to some raw or powdered garlic forms.

While fish oil supplements provide concentrated omega-3s, eating fish offers additional nutrients and is often recommended for overall health. However, some prescription-strength fish oil supplements contain higher doses of omega-3s than can be obtained from diet alone and are specifically approved for managing very high triglycerides.

Common side effects of garlic supplements include bad breath, body odor, and potential stomach upset. These are often related to the allicin content.

Fish oil can cause a fishy aftertaste, digestive issues, and in high doses, an increased risk of bleeding. Taking enteric-coated capsules can help minimize the fishy burps.

Both garlic and fish oil have anti-inflammatory properties, but fish oil's omega-3s (EPA and DHA) are widely recognized as potent anti-inflammatory agents that can help manage conditions like rheumatoid arthritis.