Are the marketing claims true? Are they calorie bargains or calorie rip-offs? That's the ongoing question with claims on food packages proliferating and food manufacturers looking for any angle to increase sales. Here are the results of two of my latest investigations.

PLANTERS NUT-RITION DIGESTIVE HEALTH MIX

Claims: "Keeping it running smoothly gets a little easier with our fiber-filled Digestive Health Mix, a succulent blend of pistachios, almonds, tart cranberries, crunchy granola clusters and sweet cherries which helps promote digestive health."

Ingredients: Pistachios, almonds, dried cranberries, whole-grain rolled oats, sugar, brown sugar, dried cherries, high-fructose corn syrup, modified cornstarch, vegetable oil, inulin (natural extract from chicory root), molasses, salt, natural flavor, baking soda, soy lecithin. Contains: pistachios, almonds, soy.

Nutrition information (serving size 32 grams): 150 calories, 8 g fat, 45 mg sodium, 17 g carbs, 3 g dietary fiber, 11 g sugars, 4 g protein.

Facts: "In sufficient quantities, inulin improves digestive health by helping to alleviate constipation, increasing the rate at which digested foods move through the intestine and stimulating the growth of healthy bifidobacteria in the intestine. Inulin 'feeds' the healthy bacteria, allowing them to out-compete some possibly detrimental bacteria in the intestine. Other health benefits of inulin include better blood lipid profiles, thus reducing the risk of heart disease, and improved mineral absorption and bone health," say Mary Ann Johnson, spokeswoman for the American Society for Nutrition and professor of nutrition at the University of Georgia. Inulin is a "prebiotic," which means it boosts the growth and activity of the good bacteria in the intestines that may promote regularity.

Additionally, the first four ingredients in the product are pistachios, almonds, dried fruit and whole oats, all of which naturally contain fiber to help with regularity, says Dawn Jackson Blatner, spokesman for the American Dietetic Association.

Fiction: "The inulin is 11th on the ingredients list after three types of sweeteners (sugar, brown sugar, high-fructose corn syrup), and I don't know if that would be a therapeutic amount of inulin," says Blatner. In fact, research shows that five to 10 grams of inulin may be needed for a measurable health benefit, adds Johnson. The nut mix contains only 0.2 grams of inulin per 32-gram serving (about an ounce).

Concerns: The consumer wishing to avoid added sugars will see that this product has four sources of added sugars: sugar, brown sugar, high-fructose corn syrup and molasses. While nuts and dried fruits are healthy in moderation, these foods would need to be limited to 1-2 ounces daily because of the relatively high calorie content: 150 calories per ounce. Most sedentary adults need only about 1,800 to 2,400 calories daily, so a few handfuls of this snack would contribute a large number of calories, Johnson says.

The serving size here is 1 ounce, or one-eighth of the container. With 150 calories per serving, it is important to portion wisely and not just snack out of the container, because the calories can add up fast. In addition, this product alone is not enough to promote healthy digestion: We need a fiber-rich diet, plenty of water and exercise to get the best effects.

The bottom line: "There is no evidence to support these claims," says Dr. Gerard E. Mullin, director of gastroenterology at Johns Hopkins Hospital. Blatner adds: "Don't rely on this to be the key to healthy digestion; instead, eat a wide variety of high-fiber foods such as whole grains, fruits, vegetables, beans and nuts, and drink plenty of water."

MUSCLE MILK (WWW.CYTOSPORT.COM)

Claims: "Muscle Milk helps grow muscle faster than gainers, whey or even creatine. This increased muscle growth is possible because Muscle Milk is the first product patterned after nature's ultimate anabolic food — human mother's milk. Locked within human mother's milk are long-held secrets to muscle growth potential previously considered impossible."

Ingredients: Special protein and lipid formulas EvoPro and Leanlipids, fructose, cocoa powder maltodextrin, vitamin and mineral mix, GCC (proprietary endogenous creatine precursor consisting of glycocyamine, betaine anhydrous), natural and artificial flavors, acesulfame potassium, sucralose, soy lecithin (more information on the CytoSport Web site).

Nutrition information (serving size, 11 ounces): 220 calories, 11 g fat (4.5 g saturated), 250 mg potassium, 110 mg sodium, 9 g carbs, 1 g fiber, 21 g protein.

Facts: According to Lona Sandon, a professor of nutrition at the University of Texas Southwestern Medical Center at Dallas, "Science exists behind the need for these proteins, but it is being simplified and applied to the promotion of muscle growth of an adult human for which human milk is not intended." And according to sports nutritionist Nancy Clark, this is a product "convenient for athletes who don't take responsibility for grocery shopping."

Fiction: What you get in this supplement you can get from eating real food. Animal-based protein from meat, milk and eggs provides the body with all the essential amino acids necessary for muscle growth. "Milk is an excellent source of leucine, which promotes muscle growth. Amino acids found in human milk intended for infants do support muscle growth, but their main function is to build antibodies for the immune system. Also, muscle growth must be stimulated by challenging the muscle with resistance. Simply drinking this supplement without resistance exercise will not provide much benefit," Sandon says.

Concerns: The calories. This is a very concentrated source of calories, making it easy to overdo. Plus it has a lot of multisyllable ingredients.

Bottom line: "Research has shown that when drunk after exercise, a glass of regular low-fat chocolate milk promotes muscle recovery and growth similar to the recommendations and claims of this product," Sandon says.

Charles Stuart Platkin is a nutrition and public-health advocate, and author of "Breaking the FAT Pattern" (Plume, 2006). Sign up for the free Diet Detective newsletter at www.dietdetective.com.