What Is Fish Oil and Where Does It Come From?

Fish oil is derived from the tissues of oily fish, such as sardines, anchovies, mackerel, and salmon. It contains concentrated forms of omega-3 fatty acids, particularly EPA and DHA, which have been extensively studied for their potential to support various areas of health.

These omega-3s are long-chain polyunsaturated fats that differ from the shorter-chain ALA (alpha-linolenic acid) found in plant-based sources like flax or chia seeds. While ALA can be converted into EPA and DHA, the process is inefficient in the human body, which is why direct intake from fish or fish oil is often emphasized.

Modern diets often contain a higher ratio of omega-6 to omega-3 fatty acids due to the widespread use of vegetable oils. Adding fish oil may help support a more balanced intake of essential fatty acids when dietary sources fall short.

Why Are Omega-3s Considered Essential Fats?

Omega-3 fatty acids are called “essential” because the body cannot produce them on its own. These healthy fats must be obtained through dietary sources such as cold-water fish, algae, or supplementation. EPA and DHA, in particular, are long-chain omega-3s that are directly involved in supporting the structure and function of cells throughout the body.

Omega-3s are incorporated into the membranes of cells, where they may help support fluidity, signaling, and nutrient exchange. They also serve as precursors to compounds that help regulate inflammatory responses, making them important contributors to balanced physiology.

EPA is often associated with cardiovascular and circulatory support, while DHA is highly concentrated in the brain and retina, where it may help support cognitive and visual function. These roles highlight the broad relevance of omega-3s in daily wellness and healthy aging.

How Fish Oil May Help Support Key Areas of Wellness

Research continues to explore the many supportive roles of omega-3 fatty acids in health maintenance. While effects vary between individuals, fish oil supplementation may help support:

• Brain and cognitive health: DHA may help support communication between neurons and promote long-term brain performance
• Cardiovascular wellness: EPA may help support healthy blood lipid levels already within the normal range and promote circulatory function
• Joint mobility and flexibility: Omega-3s may help support comfort and range of motion, particularly in active individuals
• Eye health: DHA is a structural component of the retina and may help support visual clarity
• Skin balance: Omega-3s may help support a hydrated, resilient skin barrier when paired with a nutrient-rich diet

These structure/function benefits make fish oil one of the most versatile supplements available—especially when dietary intake of fatty fish is low or inconsistent.

What to Look for in a High-Quality Fish Oil Supplement

Not all fish oil are created equal. Quality, purity, and freshness are key when selecting an omega-3 supplement. Here are several factors to consider:

Source and sustainability: Look for brands that disclose their fish species and sourcing practices. Wild-caught, small fish like sardines and anchovies are often preferred due to lower toxin accumulation and sustainability.

Molecular distillation: This process is commonly used to remove potential contaminants like mercury, PCBs, or heavy metals while preserving fatty acid integrity. Always verify third-party testing where available.

Triglyceride form: Omega-3s in their natural triglyceride form may offer better bioavailability compared to ethyl ester alternatives. Some labels clearly state this format for transparency.

Freshness and oxidation: Fish oil is sensitive to light and heat. Choose products with antioxidants like vitamin E and check for storage in dark, airtight containers. A rancid odor or taste can be a sign of poor stability.

No unnecessary additives: Clean formulations without artificial colors, flavors, or preservatives may help promote better tolerance and long-term use.

Frequently Asked Questions

How much fish oil should I take daily?

There’s no one-size-fits-all answer. Common daily doses range from 250 mg to 1,000 mg of combined EPA and DHA, depending on dietary intake and wellness goals. Always consult your healthcare provider for personalized guidance.

Can I get omega-3s from plant-based sources?

Yes, but plant-based omega-3s (like ALA from flaxseed or chia) must be converted into EPA and DHA in the body—a process that isn’t very efficient. Marine sources or algae-based DHA may be more directly supportive for some individuals.

Should I take fish oil with food?

Taking fish oil with meals that contain fat may help improve absorption and reduce the chance of fishy aftertaste. Pairing it with a balanced meal is generally recommended.

Are there any side effects to fish oil ?

Most people tolerate fish oil well. Occasional burping or mild digestive upset may occur. Choosing enteric-coated or high-quality oil may help reduce these effects.

Conclusion

Fish oil remain a reliable way to help support the body’s intake of essential omega-3 fatty acids—particularly EPA and DHA. These nutrients may help support cellular structure, brain clarity, circulatory balance, and joint comfort when used consistently and paired with a health-supportive lifestyle.

By understanding the role of omega-3s and how they function at the cellular level, individuals can make informed choices about their supplementation routines. Whether from cold-water fish or high-quality supplements, incorporating these fats may help promote long-term wellness and metabolic resilience.

Key Takeaways

• Fish oil provides EPA and DHA—omega-3s the body cannot produce on its own
• These nutrients may help support the brain, heart, eyes, joints, and skin
• Not all fish oil is the same—look for clean, third-party tested sources
• Taking fish oil with food may help support absorption and comfort
• Daily intake may help bridge nutritional gaps, especially in low-seafood diets

Disclaimer

References

1. Calder, P. C. (2015). Marine omega-3 fatty acids and inflammatory processes: Effects, mechanisms and clinical relevance. Biochimica et Biophysica Acta (BBA).
2. National Institutes of Health. Omega-3 Fatty Acids – Fact Sheet for Health Professionals. Office of Dietary Supplements.
3. Swanson, D., et al. (2012). Omega-3 Fatty Acids EPA and DHA: Health benefits throughout life. Advances in Nutrition.
4. Ghasemifard, S., et al. (2017). Comparing the efficiency of conversion of ALA to EPA and DHA in humans. Progress in Lipid Research.
5. Sarparanta, J., et al. (2018). Quality and stability of fish oil supplements. Lipids in Health and Disease.