Losing weight with minimal effort sounds like a win-win situation. But are liquid diets too good to be true?
What Are Liquid Diets?
Like the name suggests, liquid diets mean you're getting all, or at least most, of your calories from drinks.
Some liquid diets are limited to fruit or vegetable juices, or shakes, that replace all of your meals, taken three or four times a day. You do some of these diets on your own. Others need medical supervision.
Other types of liquid diets replace just one or two meals (usually breakfast and lunch) with drinks, and then you eat a healthy dinner. You may also get snack bars on some of these plans.
Do Liquid Diets Work?
Liquid diets can work, like any diet that gives you fewer calories than you use.
But the results may not last. When you drastically cut calories, your metabolism slows to save energy. Unless you change your eating habits, you're likely to regain the weight you lost after you go off the diet.
Some liquid diets work better over the long term than others. Diets that include both solid food and liquids can help overweight people control the number of calories they eat and help keep the weight off for several years.
How Safe Are Liquid Diets?
Ideally, liquid diet drinks should give you a balance of nutrients you need throughout the day, but that isn't always the case.
Very low-calorie diets (400-800 calories per day) in particular can be lacking in these nutrients and should only be used under medical supervision.
Missing out on essential nutrients can lead to side effects such as fatigue, dizziness, hair loss, gallstones, and heart damage.
Also, if you don't get enough fiber, because you're not eating whole fruits and vegetables, you can get constipated.
You also can lose muscle if you don't get enough protein in your diet.
Are Liquid Diets Used for Medical Purposes?
Doctors sometimes recommend liquid diets before certain medical procedures, or for people who are obese and need to get to a safer weight before having surgery, including weight loss surgery.
Those liquid diets are medically supervised.
How Can I Safely Get on a Liquid Diet?
First, talk to your doctor about whether a liquid diet is appropriate for you. Pregnant or nursing women, and people who take insulin for diabetes, shouldn't go on a liquid diet.
If your doctor gives you the OK to go on a liquid diet, you should also see a registered dietitian, who can go over the diet with you and make sure you're getting enough calories and nutrition. Your dietitian might recommend that you take a vitamin or nutritional supplement while you're on the liquid diet.
Before you choose a liquid diet plan, know what you're drinking. If you're considering one of the commercial diets, look at the daily values on the nutrition facts label. Be sure you're getting 100% of all the recommended vitamins and minerals.
You may also want to pick a diet that is not too low in calories and that lets you lose the weight gradually. Liquid diets that include a solid meal or two per day, or that teach you healthier eating habits, will be more likely to help you keep the weight off in the long run.