They're not sure why, however, the scientists say perhaps it's because shrimp is low in fat and contains fish oils that are good for your heart.

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The other was told to eat 30 grams of nuts (walnuts, almonds and hazelnuts) every day. (The participants were given the olive oil and nuts.) The control group was told to follow a low-fat diet consisting of fruits, vegetables, low-fat dairy products, bread, pasta and fish.

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The staples of the Volumetrics plan -- water-rich foods like brothy soups, fruits and vegetables, whole grains, low-fat dairy, lean meat, and fish -- not only help control hunger by filling you up, but they also do it on fewer calories.

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Beans, other low-fat sources of protein and certain types of fish also can reduce your risk of heart disease.

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The participants eating the low-fat diet ate three or more servings of fish or seafood a week and the same amount of fruit and vegetables as the Mediterranean diet groups.

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The most effective overall strategy to control sodium intake is to cook food at home as often as possible using fresh fruits and vegetables, grains, low-fat dairy products, fresh meat, poultry, and fish.

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It is important to take in adequate amounts of lean protein such as chicken, fish, lean red meat, egg whites, low-fat cottage cheese or a protein supplement.

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Participants in this study who ate the Med way consumed about 200 calories more per day than the participants who ate a low-fat diet heavy on bread, potatoes, pasta, rice, fruits, vegetables and fish and light on baked goods, nuts, oils and red meat.

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In general, white-fleshed fish, such as cod, tilapia, or flounder, are low in all types of fat, including omega-3s.

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The Mediterranean diet discouraged soda drinks and the low-fat diet discouraged vegetable oils, nuts, fried snacks, visible fat in meats and soup, fatty fish and tomato sauce.

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