Do fad diets work?

Dr. Mehmet Oz, MD
Cardiology (Cardiovascular Disease)

Some fads have included diets that dramatically restrict our food choices. With the cabbage-soup and grapefruit diets, advocates identified a new miracle food and built an entire eating regimen around it, a regimen that came with a promise of shedding a full 10 lb. (4.5 kg) in one week. In both of these food-idol diets, some weight does disappear quickly, mostly through loss of fluids.

Neither diet is practical or nutritionally sound, and the weight returns as quickly as it comes off. Much more recent was the earthquake that was the Atkins diet, triggered by a 2002 article in the New York Times Magazine. The Atkins regimen -- lots of meat and very few carbohydrates (including the natural sugars in fruits and vegetables) -- had been briefly popular more than 30 years earlier but became a cultural phenomenon after the Times story breathed new life into it. Market forces fed the craze, with menus reformulated to remove the last detectable carbohydrate molecule and carb-free labels slapped on foods that never contained them in the first place. Artisanal bakers wept (no carbs means no baguettes), and the überfaithful began to suffer the bad breath of ketoacidosis, which occurs when glycogen stores are too low.

But weight was being lost, lots of it. The problem was, the loss was not being sustained. There are only so many foods you can ban before people’s palates rebel, and when you pretty much take pasta, bread, fruits and vegetables off the menu, that rebellion will happen sooner rather than later. What’s more, the foods that were permitted, particularly the much-relied-on meats, can lead to inflammation and irritation, causing some physicians to worry that heart attacks and strokes could result.

Fad Diet
Donna Feldman
Nutrition & Dietetics

The short answer to "Do fad diets work?" - No. If they did, we wouldn't have an obesity epidemic. Fad diets have been around for a very long time, based mostly on half-truths and wishful thinking of the authors. Some may have a bit of science to back them up, but the diets are so restrictive and difficult, no one can stick to them. Losing weight temporarily on a fad diet does not equal success. Diet success is defined as keeping that weight off permanently. If a fad diet is impossible to follow for very long, you'll just re-gain all the weight. And much of the weight lost on extremely low calorie fad diets is water. Stick to a diet like that long enough and you'll start to lose muscle mass.

But despite the poor track record, fad diets aren't likely to go away. We just can't resist the promise of quick easy weight loss. Pay attention to these fad diet-warning signs:

  • impossibly fast weight loss, more than 1-2 pounds/week
  • magic foods or magic food combinations that "burn fat"
  • rigid rules and lists of permitted foods and "bad" foods
  • food choices restricted to a very few foods, or to just one food group
  • recommendations to eat a particular diet food product or pill (usually sold by the fad diet promoter)
  • no exercise necessary - it's truly impossible to lose weight in a healthy sustained manner without adding regular exercise to your life.
  • you'll never be hungry.
  • rigid meal plans that force you to eat differently from the rest of your family and friends

The best weight loss diet is one that focuses on healthy balanced food choices in small portions, leading to a 1-2 lb. weight loss/week. If you're able to eyeball your portions and just cut back by 1/4 - 1/2, you won't even need to count calories. Include plenty of vegetables and avoid sugary foods and beverages.

Suzy Weems
Nutrition & Dietetics

Wow! What a great question -- a simple yes or no does not apply here. Fad diets may be a 'spring board' to weight change, but most of them are going to fail to produce the results an individual is looking for over time. The gimmicks associated with the ‘fad’ are generally not sustainable and may in fact cause harm in some situations. Most often the fad diet is not successful if success is defined as long term successful and sustainable change.

Dee Sandquist
Nutrition & Dietetics

Fad diets may result in short term weight loss; however, when the diet is over and you go back to eating your previous diet weight gain will occur. Many people find they gain weight and end up weighing more than before they started the diet. When weight is lost quickly, generally fluid, muscle mass and a little fat is lost. When weight is gained after going back to previous eating habits weight is re-gained in fat (not muscle mass.) Often, the only thing a fad diet will lighten is your wallet since they require special foods, potions, or information.

Sarah Worden
Nutrition & Dietetics
Fad diets are generally a diet plan a person can stick to for the short term, but are hard to maintain longterm.  Our bodies are made to thrive on a balanced diet with food from a variety of food groups.  While fad diets may cause quick weight loss over the short term, they lack balance and generally limit certain food groups or nutrients.  Eventually a person will not be able to stick to this strick diet and likely gain the weight back. For the best results and the healthiest body, it is best for one to eat a balanced diet and stay away from fads. 
Jessica Crandall
Nutrition & Dietetics

Fad diets are called “fad” for a reason, they will come and go very quickly. In regards to their effectiveness, very rarely will it support long-term weight loss. Some diets will help you lose weight quickly however, keeping the weight off and returning to a normal lifestyle will almost always bring the weight back on, plus some. Instead of moving from one fad diet to the next, focus on healthy weight loss and maintenance. You can do this by eating small frequent meals, focusing on a good balance of nutrients and exercising 30 minutes per day about 5 times per week. This will ensure long-term weight loss success without potentially damaging your body.

Marilyn Ricci, M.S., R.D.
Nutrition & Dietetics
Fad diets get you excited. You think this time with this method I will lose weight. If you stick with the "plan" you usually do, because the plan is very different from your normal routine. Habits are very hard to break. If your habit is to eat a bag of cookies every night, a plan that stops that will enable you to eat less and decrease calories. The problem is when you stop the fad.  Did you learn anything about what to eat to be healthy and how much to eat. 
Elizabeth Casparro, MPH,RD
Nutrition & Dietetics

Fad diets can lead to quick weight loss, but there are many negative consequences that can occur from their use. First, many times they limit or avoid certain food groups and/or macronutrients (carbohydrates, proteins and fats). If carbohydrates are too low, for example, the body will start using muscle for energy first and then will eventually go into an acidic state called ketoacidosis, which can lead to death. Second, quick weight loss is usually due to water and muscle loss, not fat loss. Therefore, the weight is easily put back on once a regular diet is resumed. Third, fad diets do not address lifestyle issues or eating problem behaviors. To maintain weight loss, there need to be permanent eating habit changes as well as a balanced diet.

Amy Jamieson-Petonic
Nutrition & Dietetics

Fad diets may work in the short term, but not usually for long term health. Fad diets usually claim rapid weight loss with very little effort.. Sound too good to be true? They usually are. How do you spot a fad diet? A program that suggests to eliminate whole food groups, such as eliminating all carbohydrates, or fruits, or eating only rice alone. The best way to lose weight and be healthy is to work with a registered dietitian. You can find one at good luck!

Rosanne Rust
Nutrition & Dietetics

No! Or possibly, they do, but not for a lifetime. Often folks who "go on a fad diet", can maintain the confines of the eating patterns for a short period (months perhaps) but not for the long run of a lifetime. To modify your health, you must first examine your behaviors, and you will have to make changes, but you want them to be changes you can live with. Finding a registered dietitian to counsel you and help get you on track is the place to start.

The short answer: no. Americans spend more than $30 billion annually on weight-loss programs, products, and pills, yet after decades of such spending, there is no quick fix winner in the battle of the bulge. Researchers analyzed close to 200 weight loss studies and concluded that it is the calories, not the composition of the diet, that count when it comes to losing weight. These red flags often tell you if a diet is questionable:

  • It's the carbs, not the calories that make you fat! Eliminating broad categories of food (including sweets) can reduce calories consumed, but you're not giving your body access to fiber, phytochemicals, vitamins, and minerals found in plant foods. The high protein content can lead to loss of calcium, increasing risk of osteoporosis.
  • Lose 7 pounds in one week! This kind of weight loss usually only occurs in the first few days of a low-carb diet and is temporary due to loss of body water. Ultimate weight loss is determined by calorie imbalance, as with any other weight loss diet.
  • Celebrity-endorsed, miracle weight-loss products with a money-back guarantee! Just because a famous person endorses the product doesn't mean it is valid, just that the celebrity is being paid to do what he or she does best: act. The more miraculous the claim, the more likely you are to lose (money, not weight).
  • Naturally occurring plants or herbs will help you lose weight without risk! These products are not necessarily safer or more effective for weight loss.
Throughout the years, popular fad diets have promoted different ways to lose weight, such as eating a lot of protein or restricting carbohydrates, making dieters a little confused about what they should be eating. Fad diet claims sound appealing, telling you that you can lose weight in ten days eating only pasta, or drop thirty pounds of fat eating a high-protein diet. However, often these claims are too good to be true. Yes, weight loss comes down to calories. You may lose weight on these fad diets initially, but in order to feel energized and achieve lasting results, you need to make sure your diet is balanced.
Laura Katleman-Prue
Nutrition & Dietetics
I guess I need to understand what you mean by "work." If you mean "Do fad diets help you lose weight?" I would have to say "yes." But if you mean "Do fad diets help you solve your weight problem?"..absolutely not! 98% of the people who lose weight on a diet, regain their lost weight within three years. Anyone can force of weight on a diet, but it's like pulling off top of a weed, it comes right back unless you fundamentally change your relationship with food by changing the way you habitually think about. Real change take two things, changing your diet permanently, rather than going on a diet and changing the problematic thinking that causes you to eat too much and eat the wrong kinds of foods.
Ruth Frechman
Nutrition & Dietetics

No. Plain and simple. I don't know of anyone who has followed a fad diet and kept off the weight. Rather than follow a diet that could cause harm, identify what is making you eat more food than you need. Just being aware of what and why you eat could increase the likelihood of weight loss.

Cindy Guirino
Nutrition & Dietetics

Fad diets work for the short-term because they usually restrict a food group which restricts calories and leads to weight loss. Unfortunately, the benefits do not last long once the participant goes back to a more normal style of eating and includes the foods the fad diet had him or her avoid.

The best approach is a lifestyle approach that is nutritionally sound and one you can live with for a lifetime!




Carol Cottrill
Nutrition & Dietetics

Lose weight quickly and gain it all back—plus some!—and you’ve got the latest fad diet, and there have been plenty of them over the years.

Even though deep down we know diets don’t work in the long run, we tend to repeatedly fall for quick-fix schemes. We hear the hype about a magical food combination or some other notion and hope this diet is the one we’ve been searching for—at last, a miracle weight-loss solution.

Americans have been buying into fad diets since the early 1800s. We’re even silly enough even repeat some of these outlandish schemes. Which leads me to…

The Tapeworm Diet: In ads that date back to the late 1800s, a woman promotes easy-to-swallow, sanitized tapeworms for losing weight without diet or exercise. The dieter ingests the tapeworm, which grows inside the digestive tract, absorbing calories; the result is weight loss of one to two pounds a week. Once the target weight is lost, an oral antibiotic kills the tapeworm. Can you guess what happens next? The weight comes back—if the diet doesn’t kill you first. Believe it or not, this diet has re-surfaced in recent years.

And then there are modern day diets like:

The Atkins Diet: This popular low-carb approach leaves much to be desired as a healthy diet that most people can stay on. Although a protein-dominant regimen does result in short-term weight loss, most of us can stomach chicken breasts for only so long until we cluck, “Give me a grain of corn!” This diet rates a zero on most measures, including long-term weight loss, nutrition, and heart health. Plus it gives you bad breath and leaves you constipated.

The Bottom Line: Fads are okay when it comes to fashion, but not so great when it comes to selecting a healthy eating plan. And one size does not fit all. When you choose an eating plan, the most important consideration is to match your eating with your lifestyle and preferences.

The right diet for you is pleasurable and sustainable; it contains the foods you prefer in their freshest and most authentic form, and you eat moderate portions that satisfy you. Weight loss is slow and steady, and meanwhile you enjoy a variety of healthy food options and even the occasional indulgence. Dieting is out and delicious, real foods are in. Now that’s a trend worth following!

Nadine Pazder
Nutrition & Dietetics

Anytime that you are able to reduce your energy (calorie) intake, you will lose weight. By virtue of the fact that many "fad" diets get you to cut your calorie intake they succeed at getting you to lose weight. Does that mean that it worked? Not really. Successful dieting is measured by the length of time the excess weight stays off (6 mos. versus 6 years), and the healthful habits that you learn along the way that support a lifestyle to help you maintain the new, lower weight. Fad diets don't do that.

If what I am describing is what you are really looking for, make an appointment to speak with a Registered Dietitian. You can locate one near to you via on the home page via "Find a Dietitian".


Judy Caplan
Nutrition & Dietetics
The question is what are you trying to accomplish? Fad diets usually work in the short term for quick weight loss but rarely long term for sustainable weight loss. They are usually hard to follow and lead to return of the lost pounds.
Marjorie Nolan Cohn
Nutrition & Dietetics

Yes and NO. Fad diets, when followed a fad diet usually will promote weight loss and a lot of it in a shorter period of time. The problem with fad diets is that they generally don’t last, most often because they are too restrictive, and unrealistic to follow for a long period of time. Once off the diet the lost weight is gained back and then some. This is because when someone loses weight quickly they lose more muscle than fat which slows the metabolism, and makes it easier to gain the weight.

In a nation desperate to lose weight, the dangers of fad diets are rarely discussed. Low-carb, “miracle” diets such as Atkin’s, the Zone and South Beach are popular for a time, but once people tire of eating pizza without the crust and hamburgers without the bun, these diets fall by the wayside. Other fad diets take their place: the Detox diet, Macrobiotic diet, grapefruit diet, juice diet. The weight may come off for a short period of time, but then comes back with a vengeance once the diet is over.

The sad truth is that fad diets don’t work. But what does work? To avoid the dangers of fad diets, follow a basic rule: eat fewer calories than your body burns. People need to stop over-thinking weight
loss. Dieting doesn’t work for long-term weight loss; the only thing that works is a healthy lifestyle change. Eat a variety of healthy foods, exercise 60 minutes a day, and stop super-sizing meals!


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Important: This content reflects information from various individuals and organizations and may offer alternative or opposing points of view. It should not be used for medical advice, diagnosis or treatment. As always, you should consult with your healthcare provider about your specific health needs.