Call them what you will — nutritional supplements, meal replacements, or shakes — they’re everywhere. Magazines and television commercials tout their benefits. Sections of drugstores and grocery stores are dedicated to them. They sound promising and they come in tasty flavors. But do they deliver? What’s the best one? And, most importantly, are they something you should try?
The meal replacement (MRP) industry is big business. In the 1970s, “nutrition in a can” became widely used in hospitals and nursing homes to help nourish patients who could not eat or had difficulty eating solid food. Ensure was introduced by Ross Laboratories in 1973. In 1977, SlimFast was introduced to help with weight loss, sparking the use of meal replacements to address the obesity epidemic. And who can forget Oprah Winfrey, in 1988, pulling a wagon laden with fat across the stage to demonstrate her 67-pound weight loss on the Optifast plan? In the 1990s, Ensure and other drinks such as Sustacal, Boost, and Resource were marketed to healthy adults to supplement their nutrition. Since then, meal replacements have continued to corner the market, expanding to meet a variety of nutritional needs. Meal replacements are used for many reasons and take different forms, including shakes and bars. As a result, sales have exceeded $3 billion per year in the United States.
What are meal replacements?
Meal replacements are beverages or foods that can be consumed in place of or as part of a meal. They provide a specific amount of calories, macronutrients (carbohydrate, protein, and fat) and micronutrients (vitamins and minerals). Some meal replacements are enhanced with other ingredients, such as special types of carbohydrate, probiotics, or herbs. Many are gluten fre and lactose free. While ready-to-drink shakes and powders often come to mind, bars and prepackaged meals are considered meal replacements as well.
What are the pros and cons?
You may be very tempted to try a meal replacement. Perhaps you have tried one in the past or are using one now. If so, what prompted you to try it? The appeal of these products includes:
• Ease and convenience
• No more decision-making about what to eat
• Portion and calorie control
• Helping you follow a more regular eating pattern
• Providing more balanced nutrition
• Improve blood glucose control and possibly help reduce the dose of diabetes medication
• Helping with weight loss and weight maintenance
• Providing nutrition to someone who is recovering from an illness or surgery and whose appetite is limited
In addition to these benefits, evidence supports the use of meal replacements to help with weight and diabetes management.
Meal replacements aren’t for everyone. Despite what advertisements may claim, they aren’t miracle workers. By themselves, they can’t guarantee that you’ll lose weight or that your diabetes will be easier to manage. It’s important to know all the facts on meal replacements:
• Not all meal replacements are nutritionally balanced. Some are high in calories, while others may be too high in sugar or protein.
• You may not find a meal replacement filling or satisfying.
• Meal replacements don’t necessarily teach healthy eating habits. For example, you may not learn how to make healthful choices at holidays, while traveling or at times when meal replacements are not available.
• Meal replacements will work longer-term only when used as part of an overall effort to lose weight and manage blood sugar that includes regular physical activity, record keeping, blood glucose monitoring, and medication adjustment.
• You may eventually get bored with meal replacements. Flavors are limited, and you won’t get the satisfaction of experiencing different textures and, in the case of shakes, chewing food.
• As sophisticated as some meal replacements have become, they don’t contain all the nutrients and substances found in whole foods, such as probiotics and prebiotics.
According to the World Health Organization, more than 90% of people with Type 2 diabetes are overweight or obese.
Weight loss is often a primary goal for those who have diabetes or who are at risk. One successful strategy to help with weight loss is the use of meal replacements. Shakes or bars are available in different formulas that provide varying amounts of macronutrients that can be helpful in controlling blood glucose and appetite. Several studies have shown that the use of meal replacements can definitively lead to weight loss, especially when compared to more conventional methods of losing weight.
The benefits of using meal replacements as part of a weight control regimen are similar to those already mentioned: they’re portion-controlled; they provide a specific combination of carbohydrate, protein, and fat (and in some instances, fiber); they remove the dilemma of trying to decide what and how much to eat; and they can more evenly distribute calorie intake over the course of a day. In addition, using meal replacements enhances what is known as “sensory-specific satiety.” This phenomenon refers to the decline in satisfaction from consuming a certain type of food and the renewal of appetite from being exposed to a new flavor or a new food. Think of sensory-specific satiety in this way: It’s nighttime and you wander into the kitchen and open the refrigerator. You don’t really know what you want to eat, so you nibble on leftovers, then some cheese, then some ice cream; yet, you’re never quite able to satisfy that craving. But by limiting the number of available foods — in this case, using a meal replacement — you’re able to enhance or stimulate the incidence of sensory-specific satiety and end up eating less.
The landmark Look AHEAD (Action for Health in Diabetes) study used meal replacements. This multi-center, randomized controlled trial looked at whether intentional weight loss reduced cardiovascular outcomes in overweight people who had Type 2 diabetes. Participants in the intensive lifestyle intervention arm of the study met with a counselor and attended monthly group sessions for the first four months. They could use a meal replacement shake for breakfast and lunch and a bar for a snack. Dinner options included a conventional meal or a prepackaged dinner (another form of meal replacement). During months five through 12, participants could continue to use meal replacements. After one year, 68% of participants in the intensive group had lost at least 5% of their initial body weight, compared to just 13% in the usual care group. At eight years, the percentages were 50.3% versus 35.7%. While physical activity, record keeping, and counseling were part of the study, meal replacements were found to help those in the intervention group lose weight.
Meal replacements can be helpful in improving diabetes control by aiding weight loss. Improved blood glucose levels generally go along with losing weight. Apart from weight loss, meal replacements can be effective if you’re aiming for improved blood sugar and A1C levels. Here’s how.
• Breakfast skipper? Not eating breakfast can make it challenging to balance your blood sugars, even later in the day. Having a meal replacement in the morning is a way to easily fit balanced nutrition into your schedule and get you on the right track to better blood sugars.
• Too busy to eat regular meals? Your schedule may not always allow you to take time to eat a healthy lunch or dinner. Skipping meals or eating at irregular times can throw off your blood sugar readings. When time is tight, a meal replacement provides a balance of nutrients to help smooth out your blood sugars and keep your appetite in check.
• Trying to even out your carbohydrate intake? Consuming a steady amount of carbohydrate at your meals and snacks can make it easier to keep blood sugar levels in line. If you’re struggling to count carbs and be consistent, consider using a meal replacement shake or bar to help ensure that you balance your carb intake with your diabetes medication and your level of physical activity.
How to choose
If you’re interested in trying a meal replacement, either in place of a meal or as a snack, it’s always a good idea to first talk with a dietitian. He or she can help you choose one that best meets your needs and preferences. Not all meal replacements are alike. Many provide too much of one nutrient, such as protein, and not enough of others, such as carbohydrate. Some may contain too many calories and too much sugar, making them no different than a candy bar. In general, choose a meal replacement that contains, per serving:
• Between 180 and 250 calories for a meal, or 80 to 150 calories per serving for a snack
• 10–15 grams of protein
• 5–10 grams of fat from primarily healthy, unsaturated fat
• less than 2 grams of saturated fat
• 0 grams of trans fat
• No more than 300 mg of sodium
• 3–6 grams of fiber
• One-third to one-half of your daily vitamin and mineral needs
• Resistant starch or modified maltodextrin, types of carbohydrate that are digested more slowly, helping with glycemic control
The amount of carbohydrate in meal replacements varies widely. Always read the Nutrition Facts label for the total number of carbohydrate grams to choose one that fits closely with your goals. Some meal replacements contain sugar alcohols, types of carbohydrate that aren’t completely digested. Sugar alcohols aren’t always well tolerated and may cause gastrointestinal symptoms including gassiness, bloating, and diarrhea.
While many meal replacements are lactose free and gluten free and others are kosher, you should still read the ingredient list before purchasing and consuming any type of meal replacement product, especially if you have a food allergy or intolerance or a specific dietary requirement.
Using meal replacements
If your goal is to lose weight, meal replacements are generally used to replace one or two meals per day. Many people find that using a meal replacement at breakfast and lunch works best; they then consume a balanced, healthful meal of “real” food at dinner. Small snacks can be added between meals, as needed. Depending on your nutritional needs, you may need to include other sources of calories at a meal if you’re using a meal replacement. For example, lunch could consist of a shake along with a salad and perhaps a piece of fruit.
Meal replacements can be used in addition to a meal if your goal is to gain weight or if you need to improve your nutritional status due to a recent illness, for example. You might also eat one between meals to help boost your calorie intake. Nutrition bars that contain fewer calories than a meal shake are good choices for snacks.
If you’re not sure which meal replacement is best for you or how to use it as part of a diabetes eating plan, consult with a dietitian. You may need to check your blood sugars more often to see how the meal replacement affects your levels. And if you are losing weight, there’s a good chance that you might need less diabetes medication or insulin. Be sure to let your health-care provider know if you are using meal replacements; he or she will be able to adjust your diabetes treatment plan accordingly.
Want to learn more about meal replacement products? See “Meal Replacements and Shakes” for nutritional information and read “Meal Replacement Products: Do They Work? (Part 1)” and “Meal Replacement Products: Do They Work? (Part 2).”