Recently, meal-replacement bars, powders and beverages have been touted as a popular way of providing nutritious options for today's busy lifestyles, as well as aids for weight loss and poor appetite.

Although these products fill a specific dietary niche - providing an abundance of vitamins and minerals - their overuse can lead to sub-optimal blood-sugar control and a disparity in the ratios of vital nutrients. They are not for everyone. If you do use them, use them properly.

Eat, Drink and Be Wary

When choosing a meal-replacement item, keep in mind your purpose for using it. Is your time limited? If so, meal replacement on an occasional basis may be helpful to you.

Liquid meal replacements may also be useful to the athlete who is too nervous or upset to eat during a competition. Meal replacements are certainly convenient, but they are also expensive. An alternative may be to make a homemade blender drink of skim milk, fruit, low-fat yogurt and ice. A meal with similar calories and carbohydrate to a meal replacement drink could be a glass of milk and a piece of fruit or a piece of toast with a slice of low fat cheese.

Losing Weight

Are you looking to these items as a means to lose weight? The idea of having one drink instead of a whole meal in order to lose weight seems pretty straightforward, but weight loss is not as simple as just reducing a few calories at one time.

When we replace a proper lunch with one cup of a beverage or a one- or two-ounce meal-replacement bar, we don't fill our physical and psychological need for food. These items at a mealtime probably don't register in our minds as food, and we may feel that we are depriving ourselves. The result: we end up grazing through the cupboard in the late afternoon and eating more at supper or throughout the evening.

Although it's true that these items can result in initial weight loss, research shows that permanent weight loss is not usually achieved. For one, we do not generally change our everyday eating habits. Once we lose the weight, we often return to our old eating habits and regain the weight. Second, if we are accustomed to eating a big lunch and start having just a drink, our body says, "Hey, you're starving me - I'd better conserve more energy." Our metabolism slows down. When we resume eating normally, we gain weight.

Has your appetite and weight declined, and it is hard for you to eat foods at this time? If so, meal-replacement beverages may be helpful to help maintain your weight. You may want to select ones of higher-caloric value to help you regain some of that weight and improve your overall health. If this is the case, you may wish to still try to eat foods that are easier to consume at meal times (e.g., soups, hot cereals or casseroles) and sip on meal replacement beverages between meals to help provide extra calories.

Not all products on the market could be compared in this article, so always check the label to see what you are getting (see chart). Some bars, for example, brag about being "low fat." However, most of their calories are likely to come from sugar. Bars that contain a lot of fruit or fruit filling will be higher in sugar.

Due to the high sugar content, replacing a meal with a beverage or bar could cause you, as a person with diabetes, to experience high blood glucose. This rapid increase may result in prolonged elevated blood glucose. If, however, the beverage or bar also contains protein and fiber, your blood glucose may not rise quite so quickly. Many bars and beverages specifically intended for people with diabetes often incorporate these nutrients to prevent rapid blood sugar increases after consuming them.

A Slim-Fast Scare

In a recent article ("Slim Fast Scare,"), John Hooper, 69, of Coronado, California, explained a frightening experience he had with Slim Fast. After taking his regular 5 units of Humulin R 30 minutes before lunch, Hooper drank a glass of Slim Fast with milk instead of his usual sandwich and milk.

"I carefully read the label and figured out that it was almost identical to the sandwich in calories, carbs and sugars," wrote Hooper.

Later that afternoon, Hooper laid down for a nap. After a couple of hours, his wife was unable to wake him. When the paramedics arrived, he had a blood sugar of 22 mg/dl.

In addressing Hooper's problem, Marion Franz, MS, RD, CDE, of Nutrition Concepts by Franz, Inc. in Minneapolis, Minnesota, said that the "duration" of the glucose response can differ, and may well have been less for Hooper's lunch of Slim Fast versus his usual lunch.

"Therefore, the peak insulin response from [Hooper's] Regular insulin would occur as [his] blood-glucose levels were dropping. It may also be that the carbohydrate content of the Slim Fast lunch was less than [Hooper's] usual lunch. It sounds. more likely that there was not enough glucose from the carbohydrate [Hooper] ate when the Regular insulin was at its peak activity."

The Importance of Always Testing

It is a good idea to check your blood glucose one to two hours after having one of these meal-replacement items. By comparing the results with your normal range and discussing them with a diabetes educator you can better assess the effects of these foods on your diabetes control.

Meal Replacement Bar and Beverage Comparisons