Why is salmon only 4 star health rating?

December 31, 2025 •

4 min read

According to the Australian Health Star Rating system, some foods with healthy fats, like salmon, can receive a lower score due to their fat content, explaining why is salmon only 4 star health rating in some contexts. This happens despite its well-documented benefits from omega-3s, vitamins, and protein.

Quick Summary

Salmon's perceived 4-star rating can stem from strict rating systems that penalize high-fat foods and concerns over contaminants and farming practices, particularly with farmed varieties. Its significant health benefits often outweigh these factors for most consumers.

Key Points

Rating System Flaws: Certain scoring methods, like the Australian Health Star Rating, can penalize salmon for its healthy fat content, resulting in a lower-than-expected score.
Farmed vs. Wild Differences: Much of the health concern stems from farmed salmon, which can have higher levels of contaminants and a less favorable omega-3 profile than wild salmon.
Contaminant Concerns: Both farmed and wild salmon can contain pollutants like PCBs and low levels of mercury, but the amount is generally low and well-regulated.
Nutritional Powerhouse: The immense benefits of salmon, including heart-healthy omega-3s, high protein, and essential vitamins and minerals, often outweigh the minor risks for most people.
Sourcing Matters: Opting for certified sustainable wild-caught or responsibly farmed salmon helps mitigate environmental and health risks associated with certain aquaculture practices.
Sodium in Smoked Salmon: Processed options like smoked salmon often contain high levels of sodium, a factor that can lower its overall health profile for those monitoring salt intake.
Low Mercury Levels: Salmon is considered a low-mercury fish, especially compared to larger predatory species, making it a safe option for regular consumption.

The Context Behind the "4-Star" Label: Understanding Scoring Systems

When people question, “why is salmon only 4 star health rating?” they are often referring to a specific, context-dependent scoring method, not a universal health standard. A prime example is the Health Star Rating (HSR) system used in Australia and New Zealand, a voluntary front-of-pack labeling system designed to provide a quick comparison of similar packaged foods. The HSR calculator awards points for healthy components like protein, fiber, and fruit/vegetable content, but deducts points for 'risk nutrients' such as saturated fat, sugar, and sodium.

This is where the calculation can get tricky for salmon. Though packed with heart-healthy polyunsaturated and monounsaturated fats, salmon is a naturally high-fat food. In the HSR system, all fat, including healthy fat, increases a product's overall energy (calorie) count. Consequently, a product rich in healthy fats, like salmon, may receive a lower score than a less nutritious, low-fat alternative. This scoring anomaly does not reflect salmon's overall nutritional superiority, but rather highlights a flaw in how certain systems evaluate whole, unprocessed foods.

Examining the Differences: Farmed vs. Wild Salmon

Beyond specific rating systems, the distinction between farmed and wild salmon is a major factor in its overall health perception and public debate. While both types are excellent sources of nutrients, there are notable differences in their composition and potential risks.

Factors Influencing Salmon's Health Profile

Contaminants: Some studies have found higher levels of pollutants like polychlorinated biphenyls (PCBs) and dioxins in farmed salmon compared to wild. These contaminants accumulate from the fishmeal and fish oil in their processed feed. Both wild and farmed salmon, however, are typically low in mercury compared to larger predatory fish.
Antibiotic Use: In some farmed fish operations, antibiotics are used to combat diseases that can spread in crowded pens. This practice contributes to concerns about antibiotic resistance. However, many countries, like Norway, have significantly reduced their antibiotic use due to effective vaccination strategies.
Nutritional Differences: The diet of farmed salmon can result in a different nutritional profile. Wild salmon, with its natural diet of small fish and krill, tends to be leaner and have a more favorable omega-3 to omega-6 fatty acid ratio. Farmed salmon is often higher in total fat and calories, and can have a less ideal omega ratio due to plant-based components in its feed.
Environmental Impact: Aquaculture, while providing a source of protein that alleviates pressure on wild stocks, has its own environmental challenges. These include pollution from fish waste and uneaten food, as well as the risk of escaped fish disrupting local ecosystems.

A Balanced View: Weighing Benefits Against Risks

Despite these considerations, the overwhelming consensus among health experts is that the benefits of including salmon in your diet far outweigh the potential risks for most people. Salmon is a nutritional powerhouse, rich in several key nutrients essential for human health.

The Proven Benefits of Salmon

Omega-3 Fatty Acids: Salmon is one of the best dietary sources of the long-chain omega-3s EPA and DHA, which are crucial for heart and brain health, and have potent anti-inflammatory effects.
High-Quality Protein: As an excellent source of protein, salmon helps in repairing tissues, maintaining muscle mass, and supporting bone health.
Essential Vitamins and Minerals: It provides significant amounts of B vitamins (especially B12) for energy and nervous system function, as well as vitamin D for bone health and mood regulation. It is also loaded with selenium, an antioxidant that supports thyroid and immune function.
Astaxanthin: The carotenoid antioxidant that gives salmon its pink color, astaxanthin, is linked to numerous health benefits, including reduced risk factors for heart disease and protection for the brain and nervous system.

How to Choose the Healthiest Salmon

To navigate the differences and make the healthiest choice for you and the planet, informed decisions are key. The following comparison highlights the typical characteristics of wild versus farmed salmon.

Comparison Table: Wild vs. Farmed Salmon


Feature	Wild Salmon	Farmed Salmon
Contaminants	Typically lower levels	Potential for higher levels due to feed
Omega-3s	Better omega-3 to omega-6 ratio	Less ideal omega ratio due to diet
Fat Content	Generally leaner, lower total fat	Higher fat content, often with more omega-6s
Diet	Natural diet of smaller fish and krill	Processed feed, often with plant-based ingredients
Cost	Typically more expensive	More widely available and budget-friendly

For conscientious consumers, looking for certifications like the Marine Stewardship Council (MSC) for wild-caught salmon or the Aquaculture Stewardship Council (ASC) for responsibly farmed salmon can help ensure your choice was produced with environmental and ethical considerations in mind.

Conclusion: Beyond the Star Rating

The perception that salmon is only a "4-star" health food is an oversimplification. The rating is a product of specific calculation systems, like the HSR, that can misinterpret the value of healthy fats. While there are legitimate differences between farmed and wild salmon, including potential variations in contaminant load and environmental impact, these concerns are weighed against salmon's robust nutritional profile. For the majority of people, incorporating salmon into a balanced diet provides significant benefits for heart, brain, and overall health. The key is to make informed choices based on sourcing and preparation, and to understand that a single star rating doesn't tell the whole nutritional story.

For more detailed information on fish consumption, including mercury levels, consult reputable sources like the EPA and FDA. EPA-FDA Fish Advice

Frequently Asked Questions

The reasons can include specific rating systems penalizing its healthy fat content, concerns over pollutants in some farmed varieties, and potential environmental impacts of aquaculture.

Generally, wild salmon is leaner and has a more favorable omega-3 to omega-6 ratio. Some studies have also found higher levels of contaminants like PCBs in farmed salmon, though regulations aim to minimize this.

While contaminants like PCBs and mercury exist, their levels in salmon are typically low, especially in wild varieties. For most people, health authorities agree the benefits of eating salmon far outweigh these minor risks.

The health rating typically applies to the raw food item itself. However, preparation methods matter. For example, smoking adds significant sodium, which can lower its overall health profile for those with certain conditions.

No, salmon is considered a low-mercury fish, with levels significantly lower than larger predatory fish like swordfish and certain types of tuna.

Look for sustainability certifications from organizations like the Marine Stewardship Council (MSC) or Aquaculture Stewardship Council (ASC), which indicate responsible practices. You can also opt for wild-caught salmon when possible.

Not necessarily. The rating context is key. Salmon is a highly nutritious food, and for most people, the benefits from its omega-3s, protein, and vitamins make it a very healthy dietary choice. The best approach is an informed one.

Due to low levels of mercury and other contaminants, salmon can be enjoyed frequently as part of a balanced diet, but moderation is advised. For example, the FDA recommends 2–3 servings of fatty fish like salmon per week, especially for pregnant women.