The Medical Minute: Dieting for health calls for important decisions

July 29, 2003

By John Messmer, M.D.
Penn State Milton S. Hershey Medical Center

It's beach season and your swimsuit doesn't fit as well as last year. You're eating more fruit but for some reason the weight keeps piling on. Frustrating, isn't it?

Eating properly and maintaining a normal weight does not have to be difficult and confusing, but you will have to make some important decisions about your goals. Unfortunately, when it comes to eating healthy, you can't have your cake and eat it too -- at least not much of it.

How much should you weigh? More than half of us are overweight, defined as a body mass index (BMI) over 25, and a third of us are obese (BMI over 30). BMI is a measurement based on height and weight as it relates to body fat. The higher the BMI, the greater the risk a person has to develop additional health problems. Calculate your BMI at

If you need to lose weight, you must first accept that you eat too much. You may think you eat correctly, but if you are overweight, your total calorie intake exceeds the energy you burn. While there are genetic predispositions to being overweight or underweight, if everyone in your family was overweight, it's because everyone ate too much, not because it's normal for your family.

We get fat because in prehistoric times, food supplies dwindled in the winter. Those who were able to gain weight efficiently were more likely to survive to raise a family. Most people died of disease or injury before age 40, so heart attacks and diabetes were not much of a concern. Because we carry this legacy in our DNA, we must use our brains to overcome our genetics.

So what should you eat? Almost all food found in nature is acceptable in moderation. The key is balance -- a little fat, protein and carbohydrate in every meal -- and quantity.

Protein builds body structure and comes from meat, fish, nuts, soy and seeds. Since most protein has fat with it, most of us do not need to add fat to our diets. The type of fat, however, is important. Proteins from fish, grains, lean meats and nuts will give us the proper types, amount and balance of fats. Another bonus from protein and fat: they take longer to metabolize and tend to reduce hunger later. When we use oils, which are liquid fats, we should choose olive, corn, safflower and canola. Solid fats such as butter and margarine have more saturated fat -- use those sparingly.

Carbohydrates are starchy foods like bread, cereal, fruit, vegetables, pasta, and grains such as rice, which we use for energy. Too little and we burn our stored body fat for energy -- we feel full but sluggish. Too much carbohydrate and we convert the excess into stored fat.

Counting calories is time consuming and difficult for most people. Instead, keep portions small and include a little protein and carbohydrate in every meal. If you are trying to lose weight, you may need to tolerate a little hunger initially. After all, you are trying to make your body burn the fat. For the first few days of a reduced calorie diet, your body is trying to tell you that it can't maintain the current weight with what you are eating. That's good, because that's what you're trying to do. By the third or fourth day on lower calories, your body realizes this is the new routine and it doesn't bother you so much. Consistency is critical -- if you eat properly most days, but eat extra one day, you will not lose weight. Proper diet means every day.

What about snacks? If you are trying to lose weight, you should forget about snacks. Anything with calories adds up -- if you have snacks you will have to eliminate nutritious foods to keep your daily total down. Don't get into the trap of bargaining with yourself by saying such-and-such food is "healthy" or "low fat" so it's OK to snack on it. The bottom line is, the extra calories will prevent weight loss. If you are at the proper weight and wish to have entertainment foods, keep portions small or you will regain weight. Remember that the word "diet" means every day nutrition; if your diet is too high in calories, you will gain weight.

What about exercise? Unless you are an athlete, exercise alone won't allow you to meet your goals. You still must cut calories to lose weight. Walking or running a mile burns 100 calories but you must reduce intake by 500 calories a day to lose a pound a week. To lose weight through exercise alone, you would need to spend at least an hour every day exercising vigorously without increasing your food intake. Exercise helps, but it does not substitute for calorie reduction.

How about the Atkins diet, Zone diet, grapefruit diet, and all the other special diets? Sure, you can lose weight on any of them, but are you willing to follow the regimen for the rest of your life? If you stop the plan and resume your usual habits, you will soon be back to your usual weight. If you need help when trying to lose weight, choose a method such as TOPS or WeightWatchers that uses regular food and teaches you how to plan types of food and quantity so you can eat properly for life.

Don't bother with over the counter weight loss products -- they don't work and some can be dangerous. Though people claim success with them, studies show that anyone who actually loses weight has reduced calories and almost everyone regains their lost weight in a year. Prescription weight loss agents can help reduce appetite or prevent absorption of some fat, but weight losses are limited and the medication must be continued indefinitely to keep the weight off. Surgery is only for those who need to lose a lot of weight as soon as possible for health reasons.

The benefits of a good diet and proper weight include reduced risks of diabetes, many cancers, heart disease, Alzheimer's disease and degenerative arthritis. Children are developing diabetes because of rampant obesity, and health insurance costs are rising in part to pay for the care of those with obesity related diseases. It's never too late to feel and look better -- start now to develop good eating habits for a lifetime.

(Media Contacts)

Last Updated March 20, 2009