Protein Meal Replacement Shakes for Weight Loss: Review
Meal replacement shakes offer a simple way for you to control your calories without taking the time to plan low-calorie meals and snacks. Since these formulated beverages are not ‘real food,’ they are best suited for temporary or occasional use.
Meal replacements shakes are meal substitutes that come in two main forms: ready-to-drink and powdered mixes. Powdered mixes are formulated to be combined with water or milk prior to drinking. Nutrient content varies but even those designed for weight loss should meet about 20 to 25 percent of your daily requirement for calories and the macronutrients (carbohydrate, protein and fat). These products are typically vitamin and mineral fortified, though the amount in each shake varies depending upon factors such as type and brand. There are many varieties available such as low-carbohydrate, light, high-protein and lactose-free. There are also meal replacement shakes designed to meet the needs of individuals with specific health conditions, such as low bone mass. Though many meal replacement shakes do not contain as much carbohydrates as you would consume in a typical meal, their protein content is comparable, and high in quality. They are formulated with whey, casein, soy or, less commonly, egg or egg white protein.
Meal replacement protein shakes to lose weight
An adequate to high protein intake, particularly in conjunction with a reduced-carbohydrate diet, is effective for fast weight loss. Carbohydrates, especially fiber-rich complex carbohydrates, are essential for energy and fueling your daily activities. However, protein-rich meal replacement shakes for weight loss are often low in carbohydrate, total fat and calories per serving. Most ready-to-drink meal replacement shakes and reconstituted powdered protein shake mixes for weight loss provide about 250 calories or less per drink. Main ingredients usually include milk or a whey, egg, casein or soy protein isolate or a blend of different proteins; sugar or artificial sweeteners; cocoa (if the flavor is chocolate); and fat in the form of unsaturated oils and/or the building blocks of fats (mono-, di- or triglycerides). Other ingredients usually include natural and artificial flavorings and vitamin-mineral blends. Popular ready-to-drink protein shakes for weight loss include Slim Fast and Boost. Examples of powdered protein shake mixes include EAS Myoplex Lite, Slim Fast and Met-Rx Lite. Check this link to learn about meal replacement plans available at All About Weight.
Whey protein weight loss
Whey is a high-quality protein naturally found in cow’s milk (along with casein). According to the Whey Protein Institute, whey proteins comprise about 20 percent of the total milk protein. Whey protein is more soluble than casein protein and has a higher protein quality rating. For example, whey has a high biological value (BV) which means that it is more easily and readily broken down and used by your body. The benefits of whey appear to go beyond that and some research indicates it is beneficial for your immune system and weight control. In a recent study published in August 2011 in the Journal of Nutrition, ninety overweight or obese subjects participated in a double-blind, randomized clinical trial to determine the difference in the effects of consuming supplemental whey protein, soy protein, and an isoenergetic amount of carbohydrate on body weight and composition. This study lasted 23 weeks. Although lean body mass did not differ among any of the groups, waist circumference was significantly smaller in the whey protein group versus the other groups. Fasting ghrelin, a hormone that stimulates appetite, was lower in participants consuming whey protein versus the soy or carbohydrate.
The objective of another recent research study was to determine the effect of low-dose whey protein-enriched water beverages on after-meal satiety and total caloric intake. Among the beverages, the low-dose, whey protein-enriched water beverages significantly altered short term after-meal satiety. The participants, obese women, felt fuller for two hours after drinking these beverages but the effect did not last longer than two hours, thus not effecting caloric intake later in the day. However, the results are promising and warrant further examination. Supplemental whey protein may, over time, positively alter body composition, enhance satiety or a feeling of fullness after ingestion and aid in appetite regulation.
- Baer DJ et al. Whey protein but not soy protein supplementation alters body weight and composition in free-living overweight and obese adults. J Nutr. 2011 Aug; 141(8): 1489-94. Abstract available: http://www.ncbi.nlm.nih.gov/pubmed/21677076
- Heymsfield SB et al. Weight management using a meal replacement strategy: meta and pooling analysis from six studies. Int J Obes Relat Metab Disord. 2003 May; 27(5): 537-49. Abstract available: http://www.ncbi.nlm.nih.gov/pubmed/12704397
- Poppitt SD et al. Low-dose whey protein-enriched water beverages alter satiety in a study of overweight women. Appetite. 2011 Apr; 56(2): 456-64. Abstract available: http://www.ncbi.nlm.nih.gov/pubmed/21255627
- WebMD: Protein Shakes: http://www.webmd.com/diet/protein-shakes