What’s Involved: Dieters replace one or more meals with drinkable formulas, which are usually sold as a liquid or powder. These tend to be low in calories—but high in nutrients.
What You Need to Know: If you decide to try one of these plans, you’ll probably find that they’re easy to use and may help you lose weight.
But most people who try these diets regain the pounds as soon as they start eating solid foods again. Also, these diets do not teach people how to make healthy food choices—a necessary skill for maintaining weight.
In addition, experts agree that it’s healthier to get nutrients from food rather than a formula or supplements. Scientists still don’t know exactly how fruits, vegetables, fiber, and other foods help keep you healthy. But they know it involves a complex interaction among vitamins, minerals, and various disease-fighting compounds. So, people on liquid diets may be missing out on important nutrients.
Both approaches to weight loss may promote rapid weight loss, but not permanent fat loss. They are associated with medical problems including sensitivity to cold, brittle nails, fatigue, diarrhea or constipation, and heart problems. Weight loss by means of liquid diets can cause gallbladder problems. Sudden death may occur with very low calorie liquid diets or total fasting.
Advertisements using celebrities to promote meal replacement drinks have been widely used in the past few years. Today, however, such products are losing popularity. This is due to the fact that permanent fat loss does not occur unless the person adopts appropriate habits of diet and exercise into their lifestyle.
Medically supervised fasting or liquid diets contain high quality protein and carbohydrates. They are supplemented with vitamins, minerals and electrolytes. With careful supervision, weight loss can be accomplished safely. Such programs require careful medical screening. They may cost around $2000 to $3000.
Diet clinics may offer food plans of 1000 to 1500 calories per day. Some require you to purchase specially packaged meals available only through the company. The cost of these programs range from $250-$1000 or more. Low price initial sign-on offers may not include all costs. These programs provide variable amounts of exercise and behavior modification counseling, which is essential information needed to maintain weight loss.
Remember, permanent fat loss is achieved by following a sound plan that includes exercise, behavior modifications, and a nutritious diet.
Using diet programs that incorporate liquid meal alternatives may be dangerous, according to Jenny Yi, an assistant professor of Health and Human Performance in the University of Houston College of Education.
Liquid-based diet programs became popular in the late 1980s. They have since blossomed into a multimillion-dollar industry. Of the liquid meal alternatives, SlimFast and MET-Rx are two of the most popular and easily recognizable.
Yi said liquid-based diet programs are not regulated, leaving consumers without government help in deciding if such a diet is right for them, or how it could be managed successfully.
No long-term studies have been done to determine if any permanent problems can result from liquid diets, Yi said.
As a result, she believes they should be taken off the shelves until they’re thoroughly tested.
Some recent short-term studies indicate that health risks like high blood pressure and liver complications are associated with liquid diets, Yi said. Eating disorders may develop if dieters change their eating habits to conform to liquid-diet programs, she said.
People can and do lose weight by using liquid meal replacements. But they are three times more likely to gain the weight back than someone who lost weight by eating low-fat foods and working out, Yi said.
“How long is someone going to stay on a diet like that?” Yi asks. “When they get off, they will gain it all back.” Yi adds that the rapid weight loss that often accompanies the use of liquid meal alternatives can be dangerous.