Are Fad Diets Healthy? The Truth About Effective Weight Loss

May 31, 2023 Posted by AHW Endowment

A person cuts a small serving of lettuce, presented with the question

Everywhere you turn, there is an advertisement for a new weight loss method, supplement, or medication promising to help people lose weight fast. Weight loss is an ongoing topic of interest for Wisconsin adults–64% of whom are overweight or obesebut how can you determine if fad diets will work for you or if the results will last?

In a recent episode of Coffee Conversations with Scientists, Lisa Morselli, MD, PhD, endocrinologist, and assistant professor at Froedtert and the Medical College of Wisconsin, discussed the science behind effective dieting and the truth about some of today’s most popular fad diets.

Obesity in the United States

Obesity, or having abnormal or excessive body fat, is a common health problem, affecting 42% of adults and 20% of children in our country. It’s a significant risk factor for cardiovascular diseases (including heart disease and stroke), several cancers, diabetes, and musculoskeletal disorders. And children with obesity have a higher chance of being obese in adulthood, suffering disability, and experiencing premature death.

Unfortunately, obesity’s prevalence is not going away anytime soon: the number of obese individuals in the U.S. and worldwide has risen over the past several decades and is expected to continue to grow. While a person’s genetic predisposition plays a role in obesity, food, environment, and lifestyle are significant factors in whether you might be or become obese.

According to Dr. Moriselli, “We’re exposed to a food environment that promotes the intake of large amounts of food and foods that are unhealthy. We’re less active than we have been in the past, take medications that can cause obesity, and there are sleep issues, stress, and many other things that contribute to the rise of obesity in this country.”

The Popularity (and Truth About) Fad Diets

For obese individuals, losing weight and reaching healthy body fat cannot be done quickly or easily. Significant weight loss calls for changes in diet, activity levels, and lifestyle, all of which take time and dedication.

For some, an obesity solution that presents minimal effort or commitment is, perhaps understandably, appealing. Fad diets, or weight loss plans that promise quick and significant results, purport to require little effort. The appeal of a fad diet is simple: “Do XYZ and lose weight fast!”

Two feet stand on a scale. AHW explores the question, "are fad diets healthy" in this article.

Fad diets usually call for strictly limiting your diet or taking medication or supplements and will typically not have credible scientific evidence behind their claims.

Some popular fad diets that have gained notoriety in recent years include:

  • Cabbage Diet
  • Baby Food Diet
  • Master Cleanse
  • Grapefruit Diet
  • HCG Diet

Advertisements and endorsements around fad diets might suggest a person can lose a large amount of weight without the proven strategies that can help accomplish those things: good nutrition, exercise, and a healthy lifestyle.

Are Fad Diets a Solution to Obesity?

Can fad diets help you lose weight fast? Yes.

Are fad diets healthy or sustainable weight loss strategies? No.

Weight loss results achieved with fad diets are temporary. Once a person stops their fad diet and returns to more-normal eating habits, the weight they’ve lost is likely to return. That’s because fad diet tactics are often too difficult, inconvenient, or unrealistic to be adopted long-term.

For example, patients have asked Dr. Moriselli about the Cabbage Diet, which entails replacing all food in your diet with cabbage. Of course, you can expect to lose weight rapidly when only eating cabbage. However, limiting your diet to cabbage for the rest of your life is not something that most people can stick to or will provide you with the nutrition a well-balanced diet would.

Dr. Moriselli says, “There’s no quick fix for weight loss. Quick weight loss is usually followed by rapid weight regain. That’s why I always tell patients that weight loss is a journey. The thing to focus on is long-term sustainability.”

What Are the Risks of Trying a Fad Diet?

Though they are not scientifically backed and typically unsustainable, many people will still try fad diets in hopes of making quick progress in fighting obesity or losing weight. While the immediate and promising results of fad diets can be rewarding, for some, there are health drawbacks to adopting fad diets instead of healthily approaching weight loss, such as:

  • Nutrient deficiencies
  • Muscle loss
  • Risk of developing eating disorders
  • Lower self-esteem and an increase in body dissatisfaction
  • Impaired bone health
  • Infertility

A note reading "lose WEight' sits on a scale. Are fad diets healthy? AHW explores that topic in this blog.

Healthier Approaches to Managing Obesity

While there are no “quick fixes” to managing obesity and losing weight, there are certainly options that are better for your overall, long-term health. When evaluating which weight loss plan or program you might try, the CDC recommends avoiding those that make claims about:

  • Losing weight without exercising or dieting
  • Losing weight and eating as much as you want
  • Drastic weight loss in a short period
  • Losing weight from specific body areas
  • Unrealistic before-and-after photos
  • Exaggerated personal endorsements
  • Many small print, footnotes, and asterisks with easy-to-miss, important information.

Additionally, Dr. Moriselli reminds those interested in losing weight that there is much more to healthy weight loss than tracking numbers on the scale. “People often don’t realize that relatively small weight loss (5-10%) can lead to significant improvement in your health, she says. “Although more weight loss can significantly improve your health, focusing on how you feel rather than the number on the scale is also good.”

To hear more about the science behind effective dieting, tune into the Coffee Conversations with Scientists with Dr. Moriselli here: