Fish vs Fish Oil Supplements: Which Is Better for Your Health?

Fish oil capsules are some of the most consumed health supplements in the world. Around 20% of US adults older than 60 years regularly swallow the oily beads, likely with the belief that the oil inside provides some cardiovascular or neurological benefit.

And it might; the omega-3 fatty acids the oils purport to contain certainly have their health perks – at least, according to numerous studies conducted on people consuming oily fish; studies on omega-3 supplements have been less forthcoming.

This discrepancy raises questions: Are fish oil supplements actually as beneficial as oily fish? Or is the unfiltered flesh of the scaly animals nutritionally superior? Or, purified and lab-certified, do the supplements have the edge regarding health and safety?

To get some answers, Technology Networks posed these questions to Dr. Leigh Frame, an associate professor of clinical research and chief wellness officer at George Washington’s School of Medicine and Health Sciences.

But first, what are oily fish?

The most commonly eaten fish fall into one of two categories: white or oily.

White fish keep their fatty oils in their livers, leaving the rest of their flesh white and flaky. Examples include cod, haddock and monkfish. Oily fish store their fatty oils all over their bodies – up to 30% of their fillets can consist of fatty acids. Examples include salmon, anchovies and sardines.

Decades of research have linked the consumption of DHA and EPA to better cardiac health. Indeed, the American Heart Association recommends people eat two servings of fatty fish per week.

“Omega-3 fatty acids, particularly EPA and DHA, play a critical role in cardiovascular, cognitive, and overall health,” Dr. Frame told Technology Networks.

Plenty of people, however, don’t have the appetite for two weekly portions of mackerel, which is where the $3.08 billion global fish oil supplement market comes in.

But is this kind of substitution equally healthy? After all, as Dr. Frame points out, fish fillets contain more beneficial compounds than just omega-3 fatty acids.

Nutrition

“Whole fish provides a broad spectrum of nutrients beyond omega-3s, including high-quality protein, vitamins (e.g., vitamin D, B12), and minerals like selenium and iodine,” Frame said.

“For example, fatty fish such as salmon, mackerel and sardines are nutrient-dense and support overall health.”

Dietary selenium helps reduce inflammation and prevent lipid oxidation and platelet aggregation. Iodine is crucial for thyroid regulation.

“Fish oil supplements, on the other hand, are concentrated sources of EPA and DHA. Studies suggest that the bioavailability of omega-3s may be slightly higher from supplements (in triglyceride or re-esterified triglyceride forms) compared to ethyl ester forms often found in some fish oils. However, eating whole fish delivers additional synergistic benefits from its other nutrients.”

Potency

So, fish flesh comes with more beneficial nutrients. But, as Frame highlights, supplements can pack a higher dose of DHA and EPA – a factor that could be relevant for consumers keen on the acids’ anti-inflammatory properties.

“Fish oil capsules offer a consistent and measurable dosage of EPA and DHA, which is particularly beneficial for individuals with specific health conditions, such as high triglycerides or inflammatory disorders,” Frame said. “For instance, clinical trials often recommend doses of 2–4 grams per day of EPA and DHA to achieve therapeutic effects. Consuming this amount through fish alone may be impractical.”

“Conversely, a typical serving of fatty fish provides around 500–1000 mg of EPA and DHA, meeting general dietary recommendations for healthy adults but may not suffice for those with higher needs.”

Potential contamination

This high potency can also come with a question of purity. After all, much of the oceans are (unfortunately) contaminated with low levels of harmful substances like mercury and microplastics. If properly processed, fish oil supplements might just contain fewer of these pollutants, per gram, than fish fillets.

“Whole fish may contain environmental contaminants such as mercury, PCBs [polychlorinated biphenyls] and dioxins, particularly in larger, predatory species like tuna and swordfish,” Frame added. “Regulatory bodies advise consuming fish lower in the food chain (e.g., salmon, sardines) to minimize exposure.”

“Fish oil supplements, if molecularly distilled, can significantly reduce contaminants. Quality control is crucial, as not all supplements undergo rigorous purification processes. Look for third-party certifications, such as the International Fish Oil Standards (IFOS), to ensure purity and potency.”

Environmental cost

Aside from the impact fish oil can have on their health, consumers may also be concerned about the impact the products have on the environment.

“Overfishing and bycatch are major concerns with whole fish consumption, particularly for species like salmon and tuna,” Frame said. “Sustainable sourcing is vital, and organizations like the Marine Stewardship Council (MSC) certify responsibly harvested fish.”

The global appetite for fish oil tablets is also taking its toll on the oceans, even endangering the Peruvian anchovy. Many supplement manufacturers rely on anchovies for their raw materials. Regulations are in place to preserve anchovy juveniles and ensure future generations, but several companies known to flout these regulations are still operating in Peruvian waters.

Technological innovation, like algae genetically engineered to produce omega-3 fatty acids, may be one solution to this crisis.

“Fish oil production also has an environmental footprint, but advances in algae-based omega-3 supplements offer a more sustainable alternative,” Frame said.

“Algae-derived EPA and DHA supplements are plant-based, eliminating concerns about overfishing and reducing environmental impact.”

Conclusion

Ultimately, there’s no firm winner in the fish vs fish oil debate; they each have their respective benefits that appeal to different kinds of consumers.

“The choice between fish and fish oil supplements depends on your health priorities,” Frame surmises. “For a balanced diet rich in diverse nutrients, consuming whole fish is ideal, provided sustainable and low-contaminant species are chosen. For individuals with specific health needs or dietary restrictions, fish oil supplements offer a targeted and practical way to achieve optimal omega-3 intake.”

“Consulting with a healthcare provider can help tailor recommendations to your needs.”