The Diet Detective: 4 Summer Fruits Packed With Vitamins

Peaches

Why: They are sweet, don't raise blood sugar levels and are very low in calories.

Health Perks: One peach delivers 10 percent of the vitamin C you need and 2 grams of fiber. And peaches have a low glycemic load.

Nutrition: Serving size—one medium (2 2/3-inch diameter), calories 58, total fat 0.4g, total carbohydrate 14.3g, dietary fiber 2.2g, sugars 12.6g, protein 1.4g.

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Seek Out: According to Green, "Make sure that the stem end is yellow or cream-colored. Also, look for a well-defined crease and a pleasingly sweet fragrance. They should be soft to the touch."

Avoid: "Make sure that the peach doesn't have 'green shoulders' around the stem, suggesting premature picking. A deep, red-brown color, softening of the fruit or shriveling of the skin at the stem indicates it's over-ripe," advises Green. Never squeeze peaches: They bruise.

Storage: Don't store in the refrigerator or in sunlight. One of the better ways to ripen peaches is to place them in a brown paper bag, fold the top and leave them for a day or so.

Interesting: Peaches are originally from China, where they are considered a symbol of longevity.

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Cantaloupe

Why: One-quarter of a melon (about 15 cantaloupe balls) has only 70 calories or so, and there is nothing like a sweet piece of cantaloupe on a hot summer day.

Health Perks: It's low in calories and high in the antioxidant beta carotene, vitamins A and C and a good source of vitamins B6 and B3 (niacin), folate and potassium.

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Nutrition: Serving size: 1/4 of a large melon (about 6 1/2" in diameter), calories 69, total fat 0.4g, cholesterol 0mg, sodium 33mg, total carbohydrate 16.6g, dietary fiber 1.8g, sugars 16g, protein 1.7g.

Seek Out: Fragrant, symmetrical melons, heavy for their size, with a yellow or cream undertone and no bruises. "Another indicator is the stem: If it still has one and it won't come off easily, chances are it's not ready to eat," says Parker. Additionally, the skin color between the netting should be yellowish-buff, yellowish-gray or pale yellow—not green.

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