What was once a rest stop on the way to vegetarianism is now Hollywood's hottest diet. The pescatarian regimen—basically a vegetarian approach supplemented by fish and shellfish—is a low-fuss way to stay on the chic-eatery circuit and reap some serious benefits: It can help you lose weight, build muscle, and even improve your sex life.Little wonder, then, that this dietary lifestyle has become the choice of in-the-know, health-conscious celebrities like Olivia Wilde, David Duchovny, Common, and Ben Stiller. Top TV trainer Jillian Michaels feasts on fish-and-veggie combos, and on New Girl, the frequently shirtless Schmidt (Max Greenfield) announced on Thanksgiving that he was, for the most part, "a refined and enlightened pescatarian."
The schools of fish lovers are swelling, and the reasons are both simple and compelling. For starters, there's weight loss. Consider this: A 6-ounce sirloin delivers about 50 grams of protein—along with 360 calories and 16 grams of fat (6 of which are saturated). You get the same protein boost from 6 ounces of yellowfin tuna, for only 221 calories and 1 gram of fat. Says Dr. Sarah Samaan, a (pescatarian) cardiologist and the author of Best Practices for a Healthy Heart: "It can be hard to get enough protein with a vegetarian diet, and some of the veggie protein sources like beans and soy can bloat you." Fish eaters may also have lower incidences of certain cancers (prostate among them) than vegetarians, according to researchers from the University of Oxford. Plus, fish are the best source of omega-3 fatty acids—which lower heart-disease risk and contribute to brain health. You'll have better sex, too, since the high omega-3 content in fish increases nitric-oxide production, improving erectile function. Hooked yet?

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5 WAYS TO BE A BETTER PESCATARIAN

THINK SMALL
Mercury levels rise as you move up the food chain, which is why you should rarely eat large carnivores like swordfish, king mackerel, and shark. The best way to minimize your ingestion of toxins? Eat fingerling fish like herring, sardines, and anchovies.

GO GREEN
Unsustainable seafood tends to have more mercury, studies show, which may cancel out omega-3 benefits. The Seafood Watch app from Monterey Bay Aquarium helps you find sustainably caught or farmed fish.

MIX IT UP
To minimize your toxin intake and maximize your nutrient intake, vary your seafood diet. Pile on the small, cold-water fish; eat high-cholesterol picks, like shrimp and squid, only once a week; and avoid PCB-heavy options, such as Atlantic or farmed salmon, altogether.

CHOOSE THE RIGHT SIDES
Pineapples, bananas, mangoes, papayas, and oranges may be helpful in blocking some mercury absorption. Pair your fillets with a fruity salsa.

TRY SMOKING
Preserved fish, such as smoked trout, makes a good main-course-salad topper (add mustard dressing) and a healthy, tasty swap for sausage in a hash.

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