The Diet Detective: 3 Foods to Add to Your Summer Shopping List

Sweet Bell Peppers

Why: They're crisp, delicious, low in calories, go with almost any food, and add great color on the plate. In addition, red bell peppers have three to four times more vitamin C than citrus fruits, and green, yellow and orange bell peppers are also higher in vitamin C than citrus.

Red bell peppers are fully ripened green bell peppers. Green bell peppers are unripe and immature. Orange, yellow and purple peppers are different varieties of the bell pepper and reach their appropriate color upon ripeness. All peppers become sweeter as they ripen. Also, as an interesting side note, bell peppers contain a recessive gene that inhibits the concentration of capsaicin, which is what makes chili peppers hot and spicy.

Nutritional Information: Red bell peppers (1 cup): 46 calories; 0.45 g fat; 9 g carbs; 3 g fiber; 1.5 g protein. Green bell peppers (1 cup): 30 calories; 0.25 g fat; 7 g carbs; 2.5 g fiber; 1.3 g protein.

Health Perks: Red bell peppers are one of the best sources of beta carotene, the form of vitamin A found in plants. And red bell peppers also contain approximately 11 times the beta carotene of green bell peppers. In addition, they are an excellent source of the phytochemicals lutein and zeaxanthin, which are known to protect against macular degeneration. Bell peppers of all colors are also good sources of vitamin B6, fiber, folate, potassium and many other vitamins and minerals. And they contain the phytochemical lycopene, which has been shown to reduce the risk for certain cancers.

A 2007 study published in the Journal of Food Science compared the antioxidant activity in all four colors and found that the quantity of antioxidant phenolic compounds was greatest in red bell peppers, followed by orange, yellow and green.

Purchase Tips: Research indicates that bell peppers of all colors are among the top 10 vegetables for containing pesticide residue when grown conventionally. Therefore, it is recommended that you look for organically grown varieties.

Red Raspberries

Why: Have you eaten a sweet-tasting raspberry? It rivals any candy you can think of--and it's only 1 calorie per raspberry. Raspberries are much lower in calories than you would think--only 64 calories for 1 cup. And just 1 cup provides: 32.2 mg, or 54 percent of the recommended daily value, of vitamin C; 32 percent of your day's supply of fiber; and 41 percent of the daily recommended value for manganese, which is a trace mineral that helps to catalyze enzymes required for various body functions.

Nutritional Information (1 cup): 64 calories; 14.7 g carbs; 8 g fiber; 0.8 g fat; 1.5 g protein.

Health Perks: According to a study conducted by researchers A. Venketeshwer Rao and Dawn M. Snyder from the Department of Nutritional Sciences at the University of Toronto, Canada, and reported in the Journal of Agricultural and Food Chemistry, red raspberries contain "a wide range of polyphenolic phytochemicals (flavonoids, phenolic acids, lignans and tannins)," some of which may function as anti-inflammatory and anti-atherosclerotic and protect against LDL oxidation, thus reducing cardiovascular diseases.

Anthocyanins and ellagitannins are the major antioxidant phytochemicals present in raspberries. Ellagitannins are tannins, not commonly found in foods, which react with water to become ellagic acid, and may slow the growth of some cancer cells. Recent research has shown that the ellagic acid in raspberries is highly bio-available. Anthocyanin, the pigment responsible for the red color in raspberries, helps reduce the risk of blood coagulation, preventing the development of blood clots involved in stroke, pulmonary embolism and heart attack.