My mother told horror stories of her teenage years. She was so thin that other kids tossed her around like a baseball bat. She drank gallons of whole milk and cream, trying vainly to gain weight.

Don't despair. It is possible for most people to gain weight. We're looking for a healthy weight gain, not just adding body fat. That means, instead of loading up on junk foods and high-fat nutritional nightmares like cookies and candies, treating yourself to nourishing foods that will help you add muscle and body mass. How? With these easy tips:

• Eat three meals every day. Yes, this means you need to get up in time for breakfast, that you can't skip lunch, and that dinner actually needs to be prepared and eaten.
• Eat three snacks every day. That's right: midmorning, midafternoon and evening. In order to gain weight, you need to fuel your body at regular times. The easiest way is to set up a schedule of three meals and three snacks.
• Stop drinking non-caloric beverages. That includes diet soda, and plain coffee or tea. You're looking for calories, right? Choose skim or 1 percent milk (we want healthy calories, not fat, so avoid milk with higher fat contents), 100 percent fruit juice or sports drinks.
• Choose calorie-dense foods. That means eating potatoes, corn or peas instead of celery and carrot sticks. Or choosing a banana or cranberry juice instead of an apple or orange juice. Granola cereal is more calorie-dense than puffed rice. Read food labels for the serving size and the calories, and make it a habit to routinely choose foods that are higher in calories.
• Expand your meals. Each meal should include some type of starchy food (potato, rice, pasta, bread, cereal), fruits and vegetables, and a protein source (chicken, red meat, fish, tofu, peanut butter, legumes, eggs, cheese). Use two or three teaspoons of margarine or salad dressing with each meal to add moderate amounts of fat without going overboard.
• Exercise. Regular exercise and activity will help your body gain muscle and not unwanted fat. Thirty minutes of daily activity is plenty to get your system moving yet not so much that you're burning up tons of calories. If you are more active, you'll need to increase your calorie intake.