| KEY TERMS Gluten— An elastic protein found in wheat and some other grains that gives cohesiveness to bread dough. Some people are allergic to gluten and cannot digest products containing wheat. Lactose— A sugar found in milk and milk products that produces lactic acid during the process of fermentation. Some people cannot digest lactose and must avoid products containing milk. Liquid meal replacements (LMRs)—A general term for prepackaged liquid shakes or milk-like drinks intended to substitute for one or more meals a day as part of a weight-loss regimen or source of nutrition for people who cannot eat solid foods. Metrecal— The first product marketed as an LMR for weight reduction, introduced in 1960 by Mead Johnson. Satiety— The quality or state of feeling comfortably full. It is sometimes used as a criterion for evaluating people’s satisfaction with diets or diet products. Smoothie— A blended beverage resembling a milkshake in texture but often made with nondairy ingredients. Slim-Fast and other diet product companies market prepackaged smoothies as well as shakes. |
Description
Function
Benefits
Precautions
Risks
Research and general acceptance
Questions to ask your doctor
Resources
What is the Slim-Fast?
Slim-Fastis the trademarked brand name of both a line of diet products and a weight-management program known as the Slim-Fast Optima Diet. Slim-Fast Foods, the manufacturer of the diet products, was acquired by Unilever N.V., a company headquartered in the United Kingdom, in 2000. Slim-Fast diet shakes are perhaps the best-known products in the line, which also includes snack bars, meal bars, smoothies, cookies, and powders for reconstituting by mixing with skimmed milk. The Slim-Fast diet plan is sometimes categorized together with other plans based on liquid diet products as a liquid meal replacement or LMR diet. LMR diet products themselves are a major business in the United States, reported in 2006 to account for over $1 billion in consumer purchases each year. What are the Origins of the Slim-Fast?
Although Slim-Fast as a specific product was introduced only in the early 1980s, LMR products as a type have been on the North American market since 1960, when Mead Johnson, a company better known as the maker of such baby foods as Pablum and Dex-tri-Maltose, introduced a liquid diet formula called Metrecal. Metrecal was packaged in 8-oz cans, each containing 225 calories’ worth of product. The dieter
was supposed to drink four cans daily, for a total of 900 calories.
Metrecal itself was a rebranded food product originally designed for hospital patients or other invalids unable to digest solid foods. Named Sustagen, the liquid meal substitute consisted of a mixture of skimmed-milk powder, corn oil, and soybean flour, supplemented with vitamins and minerals. When Mead Johnson found that patients reported feeling comfortably full on Sustagen and were satisfied with it as the equivalent of a meal, the company decided to rename their product Metrecal and market it as a diet food in 1960. In the mid-1960s the company introduced Metrecal cookies, nine of which made a meal, as an alternative to the liquid formula.
Metrecal lost much of its market in the 1980s as a result of competition from Slim-Fast, which cost much less and was aggressively promoted in the mass media. In addition to lower price, the original Slim-Fast products tasted much better to most consumers than Metrecal, which had a noticeably chalky taste—so much so, in fact, that one team of researchers in Philadelphia used Metrecal to test its effects on the concentration of gastric acid in patients diagnosed with peptic ulcer. In addition to a more pleasing taste, the original Slim-Fast formula came in a wider variety of flavors and included breakfast and lunch meal bars as well as the canned shakes and a powdered formula that the dieter could mix with skimmed milk at home.
In the early 2000s, Slim-Fast lost some of its popularity due to widespread interest in the Atkins diet. The company replaced the sugar in its original liquid formula with Splenda, an artificial sweetener, and added an additional gram of fat to the formula in order to help dieters feel fuller longer. Another modification to the earlier formula was increasing the proportion of nonsoluble dietary fiber, which also increases the dieter’s feeling of satiety. The new line of Slim-Fast LMRs is called Slim-Fast Optima Hunger Control Shakes. In addition, the company has added several lines of specialized diet products for dieters with lactose intolerance, dieters interested in a low-carbohydrate weight-control plan, and dieters who prefer a high-protein diet. As of 2007, there are five separate lines of Slim-Fast diet products:
- Original Slim-Fast formula: available in ready-to-drink shakes, smoothies, meal bars, and powder.
- Slim-Fast Optima: available in shakes, meal bars, snack bars, and powder. Cookies, a new product, were added to this line in early 2007. Each serving of one of these products supplies about 8 grams or 14% of an average adult’s daily protein requirements. The products come in a range of vanilla, chocolate, peanut butter, coffee, caramel, and strawberry flavors, as well as various combinations of these.
- Slim-Fast High Protein: available in shakes and meal bars. These products contain almost twice as much protein (15 grams per serving) as the Optima products.
- Slim-Fast Easy-to-Digest: available only in shakes, this formula is lactose- and gluten-free, for people who cannot digest products containing wheat or milk.
- Products for a Lower-Carb Diet: available as shakes or snack bars.
| Slim-Fastproduct | Calories per serving | Protein(g) | Carbohydrates(g) | Fat(g) | Cholesterol((mg)) | Sodium(mg) | Potassium(mg) | Fiber(g) |
| Original shake | 220 | 10 | 40 | 2.5-3 | 5 | 220 | 600 | 5 |
| Easy to digest shake | 180 | 10 | 24-26 | 5 | 5 | 200 | 500-600 | 3 |
| Low-carb shake | 180-190 | 20 | 4-6 | 9 | 15 | 220-260 | 550 | 2-4 |
| High-protein shake | 190 | 15 | 23-24 | 5 | 10 | 220 | 550-600 | 5 |
| Optima shake | 180-190 | 10 | 23-25 | 5-6 | 5 | 200 | 550-600 | 5 |
| Original nutrition bar | 140-150 | 5 | 19-20 | 5-6 | 5 | 65-80 | 115-160 | 2 |
| Low-carb nutrition bar | 120 | 1-6 | 14-21 | 4.5-5 | 5 | 70-80 | n/a | 1-2 |
| High-protein nutrition bar | 190-200 | 15 | 20-21 | 6-7 | 0–>5 | 200 | 270-300 | 2 |
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