Tom Cruise is revving up for Mission: Impossible 4, and OK! magazine claims to know his “secret weapon.”

It’s an “extreme tuna diet.”

Really.

According to a “source” for OK!, “Tom eats two large tuna servings a day — alternating between raw sashimi and cooked tuna steaks, which he loves to grill at home.”

Fourteen tuna servings per week? That sounds like… a lot.

Is the dish about Cruise and fish true?

“No,” a rep for the actor tells us, adding, “Where do they get this stuff?”

Gossip Cop isn’t sure. Sometimes we think the tabs print rumors just for the halibut.

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