Fad diet


A fad diet is a diet that is popular, generally only for a short time, similar to fads in fashion, without being a standard scientific dietary recommendation. They often make unreasonable claims for fast weight loss or health improvements, and as such are often considered a type of pseudoscientific diet. Fad diets are usually not supported by clinical research and their health recommendations are not peer-reviewed, thus they often make unsubstantiated statements about health and disease.
Generally, fad diets promise an assortment of desired changes requiring little effort, thus attracting the interest of consumers uneducated about whole-diet, whole-lifestyle changes necessary for sustainable health benefits. Fad diets are often promoted with exaggerated claims, such as rapid weight loss of more than 1 kg/week, improving health by "detoxification", or even more dangerous claims achieved through highly restrictive and nutritionally unbalanced food choices leading to malnutrition or even eating non-food items such as cotton wool. Highly restrictive fad diets should be avoided. At best, fad diets may offer novel and engaging ways to reduce caloric intake, but at worst they may be unsustainable, medically unsuitable to the individual, or even dangerous. Dietitian advice should be preferred before attempting any diet.
Celebrity endorsements are frequently used to promote fad diets, which may generate significant revenue for the creators of the diets through the sale of associated products. Regardless of their evidence base, or lack thereof, fad diets are extremely popular, with over 1500 books published each year, and many consumers willing to pay into an industry worth $35 billion per year in the United States. About 14–15% Americans declare having used a fad diet for short-term weight loss.

Description

Definition

There is no single definition of what a fad diet is, encompassing a variety of diets with different approaches and evidence base, and thus different outcomes, advantages, and disadvantages. Furthermore, labeling a diet as a fad is ever-changing, varying socially, culturally, timely, and subjectively. However, a common definition lies in the popularity of a diet promoting short-term changes instead of lifelong changes, and that popularity has no association with a diet's effectiveness, nutritional soundness, or safety. The Federal Trade Commission defines fad diets as those that are highly restrictive and promoting energy dense foods that are often poor in nutrients.

Types of fad diets

Although fad diets are ever-changing, most can be categorized in these general groups:
Fad diets are generally restrictive, and are characterized by promises of fast weight loss or great physical health, and which are not grounded in sound science.
Some fad diets, such as diets purporting to be alternative cancer treatments, promise health benefits other than weight loss.
Commercial weight management organizations, such as Weight Watchers, were inappropriately associated with fad diets in the past.
Several factors can cause someone to start a fad diet, such as socio-cultural peer pressure on body image, self-esteem and the effect of media.

Bad diets

Although not all fad diets are inherently detrimental to health, there are "red flags" of bad dietary advice, such as:
  • Promising rapid weight loss such as more than 1 kg/week or other extraordinary claims that are "too good to be true"
  • Being nutritionally imbalanced, or highly restrictive, forbidding entire food groups, or even allowing one food or food type. In the most extreme form, they may claim that humans can survive without eating
  • Recommending eating food in a specific order or combination, sometimes based on physiological properties such as genetics or blood type
  • Recommending specific foods purported to be detoxing or to "burn" fat
  • Promises a one-size-fits-all "magic bullet" with little to no effort to include other lifestyle changes that can improve health
  • Based on anecdotal testimonials such as personal success stories, instead of medical evidence from randomized, placebo-controlled clinical trials

    Health claims evaluations

Fad diets have variable results as these include a variety of different diets. They tend to result in short-term weight loss, but afterwards, the weight is often regained.
The restrictive approach, regardless of whether the diet prescribes eating large amounts of high-fiber vegetables, no grains, or no solid foods, tend to be nutritionally unsound, and can cause serious health problems if followed for more than a few days.
A considerable disadvantage of fad diets is that they encourage the notion of a diet as a short-term behavior, instead of a sustainable lifelong change. Indeed, fad diets often fail to re-educate dieters about a healthy nutrition, portion control and under-emphasize efforts and especially physical activity, so that followers cannot acquire the skills and knowledge they need for long-term maintenance of their desired weight, even if that weight is achieved in the short-term. Several diets are also unsustainable in the long-term, and thus dieters revert to old habits after deprivation of some foods which may lead to binge eating. Fad diets generally fail to address the causes of poor nutrition habits, and thus are unlikely to change the underlying behavior and the long-term outcomes.
Some fad diets are associated with increased risks of cardiovascular diseases, kidney stones, and mental disorders such as eating disorders and depression, and dental risks. For instance, long-term low-carbohydrate high-fat diets are associated with increased cardiac and non-cardiac mortality. Teenagers following fad diets are at risk of permanently stunted growth.
Some fad diets do however provide short-term and long-term results for individuals with specific illnesses such as obesity or epilepsy. Very-low-calorie diets, also known as crash diets, are efficient for liver fat reduction and weight loss before bariatric surgery. Low-calorie and very-low-calorie diets may produce initially faster weight loss within the first 1–2 weeks of starting compared to other diets, but this superficially faster loss is due to glycogen depletion and water loss in the lean body mass and regained quickly afterward.
Diet success in weight loss and health benefits is most predicted by adherence and negative energy balance, regardless of the diet type. Fad diets, with their popularity and variety, may be useful to introduce obese individuals via a dietary plan tailored to their food preferences and lifestyle into long-term dietary and lifestyle changes under supervision by nutrition professionals. Indeed, a wide variety of diets aiming at gentle caloric restriction under supervision, including commercial, fad, and standard care diets, have shown considerable and comparable success and safety, both in the short-term and long-term. Comprehensive diet programs are more effective than dieting without guidance. According to David L. Katz, "efforts to improve public health through diet are forestalled not for want of knowledge about the optimal feeding of Homo sapiens but for distractions associated with exaggerated claims, and our failure to convert what we reliably know into what we routinely do."
There is a commonly claimed figure that "95% of dieters regain their weight after a few years", but this is a "clinical lore" based on a 1953 primary study, with newer evidence demonstrating long-term weight loss after dieting under supervision, although a 2007 review found that one-third to two-thirds of dieters had slight to no long-term weight loss based on lesser quality trials, supporting Health at Every Size according to its authors. A review reported that extended calorie restriction suppresses overall and specific food cravings.

Healthy diets

Improving dietary habits is a societal issue that should be considered when preparing national policies, according to the World Health Organization. They propose a set of recommendations for a healthy diet:
  • Achieve an energy balance and maintain a healthy weight.
  • Promote the consumption of fruits, vegetables, whole-grains, nuts, seeds, peas, beans, legumes, herbs, and spices.
  • Limit sweets and sugar.
  • Limit salt from all sources and ensure salt is iodized.
  • Limit total fat consumption and in particular replace saturated fats by unsaturated fats as much as possible, and eliminate trans-fatty acids.
The 2015–2020 Dietary Guidelines for Americans implement these recommendations in the US, as follows:
  • Follow a lifelong healthy eating pattern.
  • Focus on variety, nutrient density, and quantity.
  • Limit calories from added sugars and saturated fats. Reduce sodium intake.
  • Prefer healthier food and beverage choices, such as nutrient-dense foods. These preferences should account for cultural and personal preferences to make application easier.
  • Community support of healthy eating patterns for everyone.
Contrary to the previous editions which mainly focused on dietary components such as food groups and nutrients, the latest offer a more global approach focusing on eating patterns and nutrients characteristics as "people do not eat food groups and nutrients in isolation but rather in combination, and the totality of the diet forms an overall eating pattern". Indeed, "the components of the eating pattern can have interactive and potentially cumulative effects on health", noting that "these patterns can be tailored to an individual's personal preferences, enabling Americans to choose the diet that is right for them".
Several diets have shown sufficient evidence of safety and constant beneficial effects to be recommended. These include the DASH diet for anyone but especially for cardiac risk prevention in obesity and diabetes, the Mediterranean diet with similar indications, the U.S. Department of Agriculture "MyPlate" for healthy diet guidelines, and the ketogenic diet for reducing risk of seizures in people who have epilepsy.