7. Tuna (and Other Large Fish)
Tuna is a rich source of protein and omega-3s, but it can also contain high levels of mercury, a heavy metal that can damage the brain, kidneys, and nervous system. Mercury accumulates in large predatory fish over time, making regular tuna consumption risky — especially for pregnant women and children.
Mercury poisoning symptoms include impaired vision, muscle weakness, coordination problems, and cognitive decline. Long-term exposure is particularly harmful to unborn babies, leading to developmental delays and birth defects.
Not all tuna is equally dangerous. Canned light tuna generally has lower mercury levels than albacore or bluefin varieties. Still, experts recommend limiting tuna intake to 2–3 servings per week and varying your seafood choices.
To stay safe, stick to smaller fish like salmon, sardines, or tilapia. They offer similar nutritional benefits without the mercury buildup. Pregnant women should consult a healthcare provider about safe seafood guidelines.
