Here’s the catch: tuna is a predatory fish, which means it sits higher up the ocean food chain. That’s a fancy way of saying it accumulates methylmercury from the smaller fish it eats.
Think of it like a game of toxic telephone—every step up the chain amplifies the mercury. And while a bite here and there is no big deal, consistent overload can lead to some not-so-fun concerns, especially for the nervous system.
So, How Much is “Too Much”?
Your body isn’t trying to ruin your lunch plans; it just appreciates a little variety. The general rule from the FDA is one to two servings a week for most adults—about the size of a deck of cards per serving.
If you’re pregnant, nursing, or feeding a small child, you’ll want to dial that back to one serving. Light tuna (like skipjack) tends to have less mercury than the big, majestic albacore or yellowfin you see seared at fancy restaurants.
