9 Unhealthy, Even Dangerous Weight-Loss Diets

Jamie and Larry, creators of the Hollywood Diet, have long claimed their products and regimens will help you miraculously lose weight while you're treated, as their website promises, "like a star." Their small selection of shakes and cookies for sale, on which you are to subside for 24 hours or more, will reportedly lead to a weight loss of two to nine pounds. Extreme low-calorie diets like this can be dangerous, especially when followed for more than a couple of days, warns Los Angeles-based nutritionist Alyse Levine M.S., RD. "This diet puts your body into starvation mode, and most of the weight loss you experience in the first few days will be water weight," says Levine. Added potential side effects may include diarrhea, fatigue, constipation and nausea.

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Reportedly, celebrity fitness guru Tracy Anderson touted this fad diet to her ultra-famous clientele. The idea is to replace breakfast and lunch with tiny jarred rations of puréed food and then to eat a low-calorie dinner. Sure, babies subsist just fine on tiny, jarred rations of puréed food, and if you're a grown-up and choose to eat nothing but tiny jars of puréed food, you'll likely lose the same amount of weight you would if you ate tiny portions of any food. This leaves ease of portion control and the convenience of jarred, prepared food as this regimen's sole selling point. Granted, it's free of additives and preservatives, but don't grown-ups deserve the dignity of using forks? "This diet deprives you of the pleasures of eating real food and is not a good long-term approach to weight loss," says Levine, adding that it's much easier -- and more civilized -- to just up consumption of fruits and vegetables and decrease sodium content.

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Talk about extreme! This doctor-affiliated/monitored recent fad diet has you eating via a feeding tube. Yes, a feeding tube. A "very low-calorie, protein- and fat-rich" solution with no carbs whatsoever is pumped through a tube the size of a strand of spaghetti that is inserted through your nose and into your stomach where it empties. Your body goes into ketosis, burning your own fat at a faster pace. "The fact that one would resort to a feeding tube to lose weight is appalling," says Levine. "This very low-calorie restricted plan is no more effective for short-term weight loss than just restricting your calorie intake of regularly consumed food." Aside from that, complications from this diet may include constipation, kidney stones, dehydration, dizziness and headaches, and, Levine adds, "a more unhealthy relationship with food."

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The concept behind this diet is that water weight ebbs and flows like the tide. Because humans are also made of water, the Moon Connection website claims fasting during either a full or new moon can cleanse your body of water weight and toxins at a more accelerated pace -- up to six pounds in a single day. There's a quickie version and a more prolonged version. Fasting for short periods of time here and there might not be so bad for us, but weight loss shouldn't be the motivation, says Levine. "There's no scientific evidence that our bodies need a detox diet or cleanse," adds Levine. "Our kidneys naturally detoxify our bodies 24 hours a day by removing waste -- there's no need for a liquid fast to do so." Instead, Levine recommends simply increasing water intake to eight to 10 cups per day, keeping sodium to 2,300 milligrams or less per day, and increasing whole foods while limiting processed foods -- regardless of the moon phase.

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Based on the book "The Master Cleanser" by Stanley Burroughs, the Master Cleanse, or lemonade diet, has been around for a while and name-dropped by plenty of the Beyoncés of the world because it's a fast and easy…fast. As this miraculous elixir consists only of water, lemon juice, cayenne pepper and maple syrup, you'll lose some water weight -- but not for long, says Los Angeles-based nutritionist Alyse Levine M.S., RD. "The likelihood is that you'll gain all the weight back and more once you go back to eating solid food," says Levine. "You may also have a harder time losing weight in the future, since such low-calorie diets cause you to lose muscle mass and decrease your metabolism." So what's the point?

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We've all heard of sleeping off a hangover or a cold, right? What if you were to sedate yourself into skipping a bunch of meals? Made popular after an honorable mention in the popular '60s novel "Valley of the Dolls" and Elvis Presley's rumored participation, this is by far the laziest fad diet of them all. All you have to do is drug yourself unconscious until you wake up thinner days later. Basically, it's starvation with a side of muscle atrophy, says registered dietitian Erin Palinski-Wade. "Not only can not eating or drinking for days lead to a slower metabolism and dehydration, but the harm you will cause to all of your body's organs from taking unregulated drugs (or improper use of prescription drugs) can be fatal," she adds.

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This age-old fad diet took simplicity to the extreme, pairing down what you could eat to a few food groups to total less than 1,000 calories a day. Limiting your diet so dramatically isn't a good idea, says Erin Palinski-Wade, RD, CDE, author of "Belly Fat Diet for Dummies." "Living off of cabbage soup and a few specific foods over a period of time is not a healthy way to lose weight," says Palinski-Wade. "Vegetables are high in volume while low in calories. Not only is the calorie range so low that it may slow your metabolism, but this restrictive diet may promote nutrient deficiencies if followed long term, such as deficiencies in protein and essential fatty acids." Instead, Palinski-Wade recommends filling half your plate with veggies and the other half with lean protein and healthy, whole-grain carbs.

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Dating as far back as the 1930s, this fad diet still retains some level of popularity. The premise is simple: If you eat a grapefruit before eating anything else, drink lots of water, cut out carbs and eat lean protein, you'll burn more fat. Fans of this diet say if you do it for around 10 days, you can lose up to 10 pounds. There may be a kernel of truth to this one, says Erin Palinski-Wade, RD. "It's been suggested that eating grapefruit can help to slim the waistline and lower body weight, most likely due to the diuretic properties of grapefruit helping to shed water weight. In addition, the fruit makes a great high-volume, low-calorie option, helping to keep you full and encouraging less total calorie intake during the day." Still, isn't there just so much grapefruit one can eat?

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