What Happens if You Eat Too Much Tuna?

Eat Too Much Tuna

Tuna, a common food in many diets, is famous for its high levels of omega-3 fatty acids, protein, and various important nutrients. Nevertheless, overindulging in this seemingly nutritious fish can result in unforeseen health problems, prompting the important query: “What are the consequences of excessive tuna consumption?” 

High Mercury Content

Firstly, tuna contains a substantial amount of mercury, which is a natural element found in various water sources. Regrettably, elevated amounts of mercury can have negative effects on one’s well-being. 

Tuna TypeMercury LevelToxicity Level
Light/Canned TunaLowSafe
AlbacoreMedium-HighModerate Risk
BigeyeHighHigh Risk

If you consume too much mercury, it can accumulate in your blood and cause mercury poisoning, which mainly affects the nervous system. An individual may experience mood swings, memory problems, tremors, and reduced physical strength. Pregnant women are particularly at risk as excessive levels of mercury can harm the developing brain and nervous system of the fetus. 

Omega-3 Fatty Acids Imbalances

Although omega-3 fatty acids play a crucial role in maintaining heart health and brain function, an excessive intake of these acids can cause an imbalance with omega-6 fatty acids within the body. This discrepancy may result in a higher likelihood of bleeding, compromised immunity, and potential elevations in LDL (low-density lipoprotein), commonly referred to as ‘bad’ cholesterol. 

Saturated Fats and Cholesterols

Tuna also contains a notable amount of saturated fats and cholesterol, especially if consumed with mayo or oils, which are often found in tuna salads or sandwiches. A diet high in these fats can lead to an increased risk of heart disease and stroke.

Sodium Content

Processed tuna products like canned tuna are typically high in sodium. Excessive sodium intake is linked to hypertension, heart disease, and stroke. It can also lead to kidney damage by causing a high amount of calcium in urine, which may contribute to the formation of kidney stones.

Negative Environmental Impacts

Aside from health concerns, overconsumption of tuna contributes to overfishing, which threatens the stability of marine ecosystems. According to scientific studies, drastic reductions in populations of certain tuna species are already evident due to overfishing.

Safe Tuna Consumption Practices

According to the FDA and EPA, an optimal amount of tuna for adults is 8-12 ounces (2-3 servings) of a variety of seafood per week, focusing on fish lower in mercury such as canned light tuna, salmon, and shrimp.


Although tuna is unquestionably a healthy food, it is important to consider the negative effects of consuming too much. By monitoring portion size and how often it is eaten, people can still enjoy the nutritional advantages it offers. Additionally, making conscious decisions as consumers can play a role in maintaining the sustainability of tuna and other fish species in our oceans. 

Reyus Mammadli

As a healthy lifestyle blogger for over 10 years, I couldn't pass up healthy eating and diet reviews. I prefer to write small, understandable articles and guides for visitors, to answer the question clearly and concisely and to give the reader a starting point for further actions to improve their diet and health in general.

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