I have been a registered dietitian long enough to see nuts go up and down the nutrition roller coaster. When I was a kid, I ate a lot of nuts, especially when they were left over after my folks' bridge parties! Then low-fat diets came in and nuts went out because they are high in fat. Today, nuts are in again, and nut lovers like me are thrilled! The Dietary Guidelines for Americans put nuts in the same food group as meat because, like meats, they contain protein. But unlike meats, nuts also supply fiber, a nutrient that is essential for a healthy digestive tract. They are a top source of vitamin E, a vitamin that helps protect cells throughout the body from everyday damage. Nuts are rich in monounsaturated fat, a type of fat that is recommended in the Dietary Guidelines. "Emerging research shows that nuts can boost health in several ways," says Liz Ward, R.D., a nutrition consultant and author of "The Pocket Idiot's Guide to the New Food Pyramids." "Eating almonds, for example, may help lower total cholesterol and LDL cholesterol in people with high blood cholesterol and in people with normal cholesterol." Scientific evidence suggests that nut eaters may also have a lower risk of developing heart disease. Ms. Ward points out that many consumers are surprised when they discover nuts can be part of a weight-maintenance plan. "Dieters usually avoid nuts because they are concentrated in fat and calories. It's possible that because nuts are satisfying, people who eat them may find they automatically cut back on other foods." How can you eat nuts without overdoing it? Practice portion control. Limit nuts to about one ounce-24 almonds, 18 cashews, 49 pistachios or 14 walnut halves -three or four times per week. Once you've taken your portion, put the jar or bag away! (Keep nuts fresh by storing in the freezer or refrigerator.) Ask Mindy Q: Do peanuts have the same health benefits as other nuts? A: Even though peanuts actually are a legume, their nutrition profile is similar to that of tree nuts. Peanuts contain monounsaturated fat, protein, fiber and important vitamins and minerals. Studies show that peanuts can be enjoyed as part of a heart-healthy and weight-loss diet.