Your nutrition questions answered.

Is a vegetarian diet always best in terms of health and weight control?

The fact is that "a vegetarian diet contains the fundamentals for reducing the risk of heart disease, high blood pressure, diabetes, cancer, stroke and obesity," says Joan Salge Blake, registered dietitian and nutrition professor at Boston University and author of "Nutrition & You."

In general, "Vegetarians do not consume animal flesh, such as beef, pork, chicken, fish or seafood. Lacto-ovo vegetarians consume both milk and eggs, in addition to eating a plant-based diet of whole grains, fruits and vegetables. Lacto vegetarians will eat milk products, such as cheese, milk and yogurt, in addition to their plant-based diet, but they do not eat eggs. Vegans consume no animal products whatsoever, which means no eggs, milk, butter or gelatin," explains Anne VanBeber, associate professor and chairwoman of the Department of Nutritional Sciences at Texas Christian University.

One of the main reasons vegetarian diets are healthier is that they're typically lower in fat and cholesterol, higher in fiber and more moderate in protein and calories than other diets. Plus, fruits, vegetables, whole grains, legumes and nuts contain a variety of antioxidants known to promote health and prevent the onset or promotion of disease.

However, simply eliminating meat and animal products does not mean one's diet is automatically lower in fat and calories or higher in health-promoting nutrients, according to VanBeber.

"Not all vegetarian diets are created equal," says Janet Brill, author of "Cholesterol DOWN."

"Vegetarian diets require careful planning to ensure consumption of all the nutrients required for good health. Highly restrictive, poorly planned vegetarian diets could lead to deficiencies in protein, calcium, iron, vitamin B-12 and zinc, to name a few. What's more, just because the diet is vegetarian does not ensure weight control. One could still create a calorie excess (eating more than one expends) on this type of diet, which would result in weight gain," she said.

For instance, those vegetarians who consume dairy products have to make sure they don't overload on full-fat cheeses. Ounce for ounce, the cheddar on top of the cheeseburger has more calories and heart-unhealthy saturated fat than the burger, said Salge Blake.

VanBeber has other concerns as well: Care must be taken to improve the absorption of the nonheme iron from plant foods, to prevent anemic conditions. Vitamin C-rich foods should be included in all meals to enhance the absorption of nonheme iron found in foods such as whole grains, legumes, raisins, molasses, spinach, broccoli and almonds.

Bottom line: "Moving toward a plant-based diet is one of the best ways to boost your health, protect against disease and keep your weight in check," says Brill. "Just make sure to do your homework."

What does it mean when a food product claims it's a "high" or "good" source of a nutrient?

According to the U.S. Food and Drug Administration, which regulates those terms, the terms "high" and "good" focus on nutrients for which higher levels are desirable. To qualify for the "high" claim, the food must contain 20 percent or more of the recommended daily value for that nutrient in a serving. "Good source" means a serving contains 10 percent to 19 percent of the daily value for the nutrient. Approved synonyms for high are "rich in" or "excellent source."

Is there a special order used for the ingredients list on a food label?

The label is regulated by the FDA, which requires food manufacturers to list ingredients in "descending order of weight (from most to least)." So, if you want to limit added sugar, you probably don't want to see added sugar (e.g., corn syrup, high-fructose corn syrup, fruit juice concentrate, maltose, dextrose, sucrose, honey or maple syrup) on the list at all, but even in a worst-case situation, it should not be one of the first several ingredients.

Will artificial sweeteners make you fat?

Recent research has made us all wonder if we're doing ourselves more harm than good by drinking diet soda — are we?

"Animal research suggests the possibility that the dissociation of sweet taste from calories makes it tougher for the appetite center to track calorie intake," says Dr. David L. Katz, a professor at the Yale School of Public Health, who also says that artificial sweeteners might be feeding our "sweet tooth."

"The more sweet we consume, the more we need in order to feel satisfied. Artificial sweeteners may bump some sugar and calories out of the way immediately, but at the cost of cultivating a preference for ever-sweeter food (the commonly used artificial sweeteners range from 300 to 1,200 times sweeter than sugar)," he adds. The problem is that those calories might sneak back in elsewhere.

Bottom line: Still nothing definitive other than a few studies, but I would use artificial sweeteners sparingly.

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.