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Rating Alternative Diets for Seniors


Slim Fast Diet for Seniors

Though there are lots of liquid diets around -- some of which are medically supervised and some, like Slim-Fast, which are not -- they all basically offer quick weight loss by substituting a sweet-tasting nutritionally fortified shake or bar for a meal.

Quick Take

  • A liquid diet plan that centers around meal replacements and snacks
  • Incorporates three servings of fruits and at least four servings of vegetables into the daily diet plan
  • Offers two calorie levels: 1,200 and 1,500 calories a day

This Diet Is Best For

People who like the taste of Slim-Fast products and find the convenience of a portable meal-replacement shake or bar appealing

Who Should Not Try This Diet

Anyone who doesn't like fruit or milk shakes or needs to eat more volume at meals to feel satisfied. It's not for people who need counseling or other dieters to talk to, since it provides no face-to-face encounters for support.

The Premise

In the past, liquid diets developed a bad reputation because dieters were restricting their intake to only 500 to 800 calories a day and getting sick -- even dying -- as a result of their weight-loss efforts.

But the liquid diet industry has cleaned up its act, and now companies like Slim-Fast, which has been around for more than 25 years, offer a safer program. Like many other diet programs, today Slim-Fast offers an online dieting community complete with an online weight-charting tool, coupons, a personal food and exercise diary, chat sessions with registered dietitians, a weekly newsletter, and the opportunity to hook up with an online Slim-Fast Buddy. There is no one-on-one counseling, however, either on- or offline.

The Rationale

Most liquid diets imply, if not promise, quick weight loss, suggesting you can satisfy your sweet tooth and curb your appetite at the same time with liquid meal replacements. Slim-Fast falls into that category, though as liquid diets go, it's one of the more responsible plans.

Total calories don't go below 1,200 a day, and the plan includes lots of fruits and vegetables in addition to the Slim-Fast foods and snacks. Liquid diets are appealing because of their simplicity and convenience. For some people, that simplicity and convenience spell success.

Eating on the Slim Fast Diet

Slim-Fast's meal replacements make up two meals a day during the weight-loss phase of the plan. Buying the company's products, which include Ready-to-Drink shakes, Snack Bars, Meal-On-The-Go Bars, Slim-Fast Powders, Breakfast and Lunch Bars, and Juice-Based Ready-To-Drink Shakes (they contain only four percent real juice), then, is mandatory.

You can find the products for sale online as well as in most supermarkets and drugstores. The 11-ounce shakes are the main attraction and cost about $1.25 each. The meal replacement bars cost about $1.00 each. Though dairy products are not part of the basic diet plan, the meal replacements are fortified with calcium, vitamin D, and riboflavin, as well as fiber.

The products are low in fat (only about one to three grams per shake), but they also are high in sugar. The one "real meal" a day allowed during the weight-loss phase consists of 4 to 6 ounces of poultry, fish, or lean meat; 1/2 baked potato; 1-1/2 cups steamed vegetables; a large salad; and a piece of fruit. In addition to a Slim-Fast snack, two pieces of fruit are allowed as snacks each day.

As the dieter reaches goal weight, the plan allows regular foods at two meals a day, with a Slim-Fast meal replacement at only one meal a day. However, there is no instruction for weaning yourself away from Slim-Fast products altogether, leaving dieters dependent on the products forever.

What the Experts Say

The Slim-Fast diet should result in weight loss. But dieticians question whether any liquid diet can actually train people to eat right, which is what changing your eating habits should be all about, says Keith Ayoob, Ed.D, R.D., pediatric nutritionist and associate clinical professor in the pediatrics department at the Albert Einstein College of Medicine of Yeshiva University. Losing weight is simply a benefit of eating right, he says.

If you follow the plan as suggested, a 1,200- to 1,500-calorie diet should result in a gradual weight loss for most people. However, for anyone who is extremely overweight, 1,200 to 1,500 calories may be too low to begin with and no formula is given for increasing the calorie level. Slim-Fast's informational brochures do mention physical activity, but they don't emphasize it enough.

Slim-Fast's diet may be a useful starting point for some people who need a gimmick to get them going, but it offers very little education or advice about entering the real world of fast food, restaurants, and family get-togethers, nor does it offer tips for permanently adjusting eating habits. Because the diet is centered around Slim-Fast products, with only one "real meal" a day, your diet could fall short of fiber (even though Slim-Fast products have some fiber added) and lead to constipation.

Though the products are also fortified with a variety of vitamins and minerals, they don't contain all the disease-preventing phytonutrients found naturally in food. Most of the products are also quite high in sugar -- not good if you've already got high blood sugar or insulin resistance.

In addition, the Slim-Fast products are fortified with iron, a nutrient you don't need more of now that you're 50 or older. And if you opt for the 1,200-calorie-a-day plan, it's unlikely to provide all the nutrients your body needs without a multivitamin supplement.

Calorie quota: 1,200-1,500 a day

Yes: Slim-Fast products, fruits, and vegetables

No: Regular foods at two meals a day; sweets, other than Slim-Fast shakes and bars

Other similar diets: Cambridge Diet

The TOPS diet for seniors will be discussed in the next section. Continue to the next page to find out what "TOPS" means.

To learn more about senior health, see:


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