Eating Too Much Seafood: Understanding the Health Risks

Seafood is a staple in many diets around the world, offering a wealth of health benefits from omega-3 fatty acids to essential minerals. But can there be too much of a good thing? If you've ever wondered what happens if you overeat seafood, you're not alone. Many people wonder if there’s a limit to how much seafood is healthy, especially with popular options like prawns, crabs, and lobsters.

While seafood is packed with nutrients, consuming certain types in excess can lead to increased exposure to heavy metals like mercury. However, making mindful choices and moderating portions can significantly reduce this risk. Let’s dive into the health aspects of consuming seafood.

How Much Seafood is Too Much?

Seafood is packed with essential nutrients, but consuming large quantities could lead to some undesirable side effects. Many types of seafood, particularly larger fish like tuna, swordfish, and certain shellfish, can contain high levels of mercury. Eating too much seafood, especially these types, may increase your exposure to heavy metals, which can have serious health consequences over time.

The Singapore Food Agency (SFA) conducts regular tests to ensure that locally available seafood contains safe levels of heavy metals, including mercury. The SFA also suggests prioritising seafood with lower mercury content for better health outcomes for regular consumption.

Potential Side Effects of Overconsumption

Overeating fish or shellfish can lead to several side effects. Below are a few key risks to be mindful of:

Mercury Poisoning:

Consuming seafood that is high in mercury can have significant health risks. Mercury is a heavy metal found in various fish and shellfish, particularly larger species like sharks, swordfish, and certain types of tuna. 

Mercury can accumulate in the body when consumed in excessive amounts, leading to mercury poisoning. Symptoms may include fatigue, memory loss, and concentration difficulties. In severe cases, long-term exposure can result in neurological damage, affecting motor skills, vision, and hearing. Pregnant women and young children are particularly at risk, as mercury can adversely impact foetal and early childhood development.

Cholesterol Concerns:

While seafood such as prawns and lobsters are often chosen for being low in saturated fat, they can be relatively high in cholesterol. For individuals managing cholesterol levels, overconsumption of these seafood varieties may pose risks. Elevated cholesterol, particularly low-density lipoprotein (LDL) cholesterol, can lead to heart-related issues, including increased risk of heart disease and stroke.

Therefore, those with a history of high cholesterol or related cardiovascular conditions should be cautious about their intake and consult with healthcare providers for personalised dietary advice.

Shellfish Allergies:

Shellfish allergies are among the most common food allergies, and consuming large quantities of shellfish like crabs, prawns, or squids can increase the risk of an allergic reaction. Symptoms can vary among individuals, including mild discomforts such as hives, itching, or gastrointestinal issues. In more severe cases, exposure can trigger anaphylaxis, a life-threatening condition that requires immediate medical attention. 

Individuals with known allergies should be particularly vigilant and consult with an allergist . It's also important to note that shellfish allergies can develop at any age, even if someone has previously consumed shellfish without issues.

Certain types of seafood present unique challenges when overconsumed. Let’s look at the possible disadvantages of eating prawns, crabs, and squids:

• Crabs: While a delicious source of protein, eating too many crabs can increase your intake of sodium and cholesterol. For people with high blood pressure or heart conditions, this can pose risks.
• Prawns: Although prawns are a low-fat option, they are high in cholesterol, which can lead to heart issues if eaten too frequently.
• Squids: Rich in protein and low in fat, squids can be a healthy choice. However, frying it can make it calorie-dense and hard on the digestive system when eaten too often.

How to Enjoy Seafood Safely? 

When eaten mindfully, seafood can still be a healthy and delicious part of your diet. Here are a few tips for safe consumption:

Choose Lower-risk Seafood

Opt for seafood like salmon, cod, haddock, and scallops [link], all of which have lower mercury levels compared to larger species. These options are also rich in omega-3s and offer a variety of flavors and textures for diverse meal planning.

You can also opt for smaller fish like sardines, anchovies, tilapia, and shellfish such as shrimp, clams, and oysters. These seafood options also tend to have lower mercury levels and contaminants due to their shorter lifespans and lower position on the food chain.

Incorporating a variety of these lower-risk options into your diet allows you to enjoy the health benefits of seafood without the concerns associated with larger, high-mercury species.

Monitor Portion Sizes

Sticking to 2-3 servings a week can help you balance your intake and minimise potential risks. Health experts recommend consuming 2-3 servings of seafood per week, where a single serving is typically about 85-115 grams (3-4 ounces) of cooked fish.

This portion is about the size of a deck of cards or the palm of your hand. Pregnant women, children, and those who consume large quantities of seafood should particularly focus on lower-mercury options like salmon, sardines, and tilapia. High-mercury fish, such as swordfish and king mackerel, should be consumed less frequently to minimise health risks.

Select Sustainable Seafood

Knowing more about seafood sustainability is an ocean-friendly choice while still enjoying the health benefits of these bounties. 

Look for seafood with eco-certifications like the MSC EcoBlue label to support sustainable fishing practices and protect marine ecosystems.

Eating Seafood: A Balanced Seafood Diet is Key