Meal replacement shakes and products can help take the guesswork out of what and how much to eat, which can may make it easier for some people to lose weight. It helps minimize the need to count calories, points or carbohydrates and limits the choices you have to make when on a diet. Some types of shakes may be more effective than others for this purpose, however, and you can take certain steps to help make it more likely that you maintain any weight you lose while using these products. Be sure to check with your doctor before starting any weight-loss diet to make sure it is safe for you.
Meal Replacement Shake Effectiveness
Anything that helps you eat fewer calories throughout the day can help with weight loss, including drinking a meal replacement shake instead of eating a higher-calorie food-based meal. A review article published in the International Journal of Obesity and Related Metabolic Disorders in 2003 found that diets using meal replacements that are vitamin and mineral fortified, for one or two meals, which contain between 800 and 1,600 calories per day, can safely help you lose a significant amount of weight and improve the risk for obesity-related diseases. If you don't get bored with the shakes and return to eating a more regular diet, these shakes can result in a significant amount of weight loss. In a study published in The Central European Journal of Medicine in 2014, 72 percent of participants lost at least 5 percent of their starting weight by using meal replacements for 12 months, and about 19 percent of participants lost 15 percent of their starting weight.
Best Type of Meal Replacement
Choosing meal replacement shakes with a higher protein content may help you maintain more muscle while losing the same amount of weight overall, according to a study published in Nutrition Journal in 2008. The more muscle you have, the higher your metabolism, so maintaining muscle during weight loss is important in helping to limit weight regain. If you're using protein shakes for meal replacement, look for those that have at least 15 grams of protein per serving and don't contain hydrogenated oils, artificial sweeteners or high-fructose corn syrup.
Choosing a meal replacement shake that's low in fat may not be the best idea, as low-fat products tend to be higher in sugars, which isn't good for weight loss purposes. A low-carbohydrate high-fat meal replacement may be better for fat loss than a moderate-carbohydrate low-fat meal replacement, according to a study published in the International Journal of Food Sciences and Nutrition in 2007.
Those who have a tendency to snack will be happy to note that a study published in the International Journal of Obesity in 2005 found that people lose about the same amount of weight if they follow a meal replacement program with or without snacks as long as they stick to the same caloric intake per day.
Compared to Weight Loss Diets
Meal replacement shakes may be just as effective, or more effective, than food-based diets for weight loss. During the course of a 40-week study published in Nutrition Journal in 2010, 62 percent of participants who used a meal-replacement diet lost at least 5 percent of their original weight compared to just 30 percent of people who followed a food-based reduced-calorie diet. Another study, published in The Journal of Nutrition in 2004, found that using meal replacements for two meals and eating a low-fat dinner was just as effective as following a structured weight-loss diet using regular foods from the grocery store and those who used meal replacements were more likely to stick to their diet.
Chance of Regaining Lost Weight
It isn't easy to maintain a significant amount of weight loss regardless of what type of diet you use to lose weight. A study published in Obesity in 2014 found that people who followed a low-energy-density diet without using meal replacements were more likely to be able to maintain a weight loss of about 13 pounds than those who used meal replacements either with or without a low-energy-density diet. A low-energy-density diet involves eating mainly foods that are lower in calories per gram, such as nonstarchy vegetables, fruits, broth-based soups and lean protein foods.
You can take some steps to help maintain any weight loss you achieve through the use of meal replacement shakes, however. A study published in Eating Behaviors in 2014 noted that people who used certain behavior changes, such as regularly weighing themselves, using step counters and continuing to use meal replacements, only regained 14 percent of the weight they lost on a meal replacement diet after a year, compared to a weight regain of about 56 percent for those who didn't take these steps.
In Combination With Other Strategies
Dietary changes alone will provide similar benefits to a combination of diet and exercise in the short-term, but a combination of diet and exercise is more likely to result in longer-term weight loss, according to a review article published in the Journal of the Academy of Nutrition and Dietetics in 2014. Exercise has a number of weight-loss benefits, but adding a weight-loss supplement probably won't increase the benefits of a meal replacement diet. A study published in the Journal of Strength and Conditioning Research in 2011 found that people using a meal replacement once a day and exercising three days a week, including resistance training and 30 minutes of cardio, experienced decreases in body fat and increases in strength, but that adding a thermogenic weight loss supplement didn't help further these benefits. If you try to lose weight without doing any resistance training, you'll lose about 25 percent muscle instead of mostly fat.
Safety and Effectiveness for Diabetics
Meal replacement shakes can sometimes be high in sugar and carbohydrates, which has led to some concern that they may not be appropriate for people with diabetes or metabolic syndrome. However, a study published in Diabetes Education in 2008 found that using portion-controlled meal replacements resulted in greater weight loss and less weight regain after 1 year for diabetics than a standard food-based diet. According to a review article published in Diabetes Spectrum in 2013, the American Diabetes Association agrees that meal replacement shakes can help diabetics lose weight, but notes that it may not be possible to maintain this weight loss if the use of the meal replacement shakes is discontinued after weight loss. The article recommends that diabetics look for shakes that have no more than 2 grams of saturated fat and no trans fat and that the carbohydrates per serving meet the individual's goals for carbohydrate consumption. In those with metabolic syndrome, as in the general population, a high-protein meal replacement diet may help you lose weight and improve your symptoms better than a standard-protein meal replacement diet, according to a study published in Diabetes/Metabolism Research and Reviews in 2010.
Fitting Shakes Into a Healthy Diet
It isn't advisable to drink meal replacement shakes for more than two meals per day unless you're on a medically supervised diet. Meal replacement diets typically recommend drinking shakes for breakfast and lunch and then eating a balanced low-fat dinner. Once you've reached your goal weight, you can't go back to the same eating habits as before, or the weight will come back. You'll need to transition into healthier eating habits and remember that your new, smaller body requires less food than you used to eat before your weight loss. Divide your plate equally between fruits, non-starchy vegetables, whole grains and lean protein at each meal to get about the right portion size and mix of essential nutrients. Use healthier cooking methods, such as baking instead of frying, and limit the amount of sodium, sugar and fat you consume. You'll also find it easier to maintain your weight loss if you continue exercising regularly, including both cardio and strength training.