I'll Have the Swordfish, Please

The swordfish feeds by ambushing barracuda, tuna, mackerel, flying fish, and squid. It is also a tasty alternative to steak if you're worried about your heart—but you shouldn't eat it often.

By Terry Dunkle

I took Mary and the kids out to dinner the other night, and there on the fancy-schmancy menu was a porterhouse steak. I was tempted to order it, but it reminded me of my friend and former co-worker, Dr. John Renner.

John was president of the National Council Against Health Fraud and loved to expose quacks. He was so smart, I hired him as chief medical officer of an online daily personalized news service that I was building.

At first, John was just a pleasant voice on the phone—we'd never met. Then one day he traveled from his home in Independence, Missouri, to my office in Connecticut. While waiting for him at the airport, I noticed a grossly overweight man—at least 350 pounds—trying to drag a suitcase through a door that wouldn't stay open. I jumped up to hold the door. "Are you Terry?" he asked. It was John.

As we walked to my car, John, between gasps for breath, told me that his weight had been normal until eight years earlier, when he broke a hip in a riding accident and was laid up for months. His corpulence embarrassed him, and as a physician he knew it was dangerous.

Like so many of us, however, John he had trouble resisting the call of his stomach. At dinner, after polishing off a porterhouse steak with mashed potatoes and gravy, he asked the waitress to bring him a hot-fudge sundae topped with whipped cream and nuts. When it arrived, he lifted his spoon, grinned at me, and confided, "I like to be good to myself."

One morning about two years later, John was emptying a plastic watering can into a potted plant in his office when he felt a pain in his chest. He died during emergency heart surgery. He was 68.

There was no way I could order the porterhouse after thinking about John. But I still craved something I could sink my teeth into. Like John, I wanted to be good to myself—only in a way that was perfectly healthful.

And suddenly I found it, hiding on the back page of the menu: swordfish.

Swordfish eyes are heated for better hunting. (University of Hawaii)

I love swordfish, not just for its nutritional properties but also for what the animal represents. Xiphias gladius (Latin for "sword fish") is a mighty hunter. It has no enemies, not even sharks. It grows to 14 feet and 1000 pounds by ambushing tuna, barracuda, mackerel, flying fish, and squid.

Since squid are jet-propelled, it takes a nimble fish to catch them. Swordfish snap them up like flying popcorn. A swordfish can sprint as fast as 54 miles per hour—thanks in part to a recently-discovered gland on their head that spreads a layer of drag-reducing oil on their skin.

The secret isn't just speed, however. Nor is it intelligence—a swordfish's brain is smaller than a grape. Swordfish also carry special equipment akin to our night-vision goggles.

Wrapped around each of the swordfish's eyes is a special organ that generates heat—enough to warm the retina by 25 degrees F. Heated retinas have a faster "shutter speed," making them better at spotting movements. At cold depths, where the eyes of other fish scan at five frames per second, the swordfish scans at 40—fast enough to detect the flicker in a TV screen. Nothing can escape it.

My swordfish steak came to the table on a big plate with a dollop of salsa and a colorful spring salad. Criss-crossed by grill marks and glistening with juice, it cut just like a beef steak. But since it hadn't been overcooked (the easiest way to ruin swordfish), it was more tender than the finest porterhouse you could order at Sparks or any other fancy New York steakhouse.

It outshone the porterhouse nutritionally, too. Look at this comparison:

Porterhouse Steak vs. Swordfish (6-oz Serving)

As you can see, swordfish is much lower in calories and fat—especially saturated fat, which clogs arteries and causes heart attacks and strokes. What's more, swordfish is rich in omega-3 fish oils, which offer almost magical protection for the heart. In a 2003 study that followed 2033 heart-attack victims for two years, the death rate among those who ate fish twice a week was 29-percent lower than those who didn't.

You shouldn't eat swordfish more than once a week, however—and if you're pregnant or under 16, not at all. Reason: As a predator at the top of the food chain, a swordfish concentrates mercury in its flesh. Ingesting too much mercury can be harm your brain, heart, kidneys, lungs, and immune system.

Still, a swordfish steak now and then is a delicious alternative to a fatty slab of beef. If you're skeptical, next time you fire up the Weber, try this easy recipe from Chuck, the Fishing Chef. How I wish I'd shown it to John!

Grilled Swordfish with Citrus Salsa

This dish is not only healthful, but colorful. And although it requires at least an hour of marination beforehand, it cooks in just a few minutes. Be careful not to overcook. Serve with a fine chardonnay or pinot noir.

4 seven-ounce swordfish steaks
3 oranges, peeled and diced
2 limes, peeled and diced
1 lemon, peeled and diced
1 cup red, green, and yellow bell
   peppers, diced
1 medium red onion, diced
1/2 cup black beans, cooked
1-1/2 T cilantro, chopped
1 T mint, chopped
1 T sugar
1 fl oz rice wine vinegar
Salt and pepper to taste

Mix all the ingredients except the swordfish, and marinate for one to two hours. Brush the swordfish with oil, and grill just until the juices run clear. Top the swordfish with the citrus salsa. Serve with rice and a salad.