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It seems like every other day there’s a new diet being touted as the best way to “lose weight” and “be healthy”. Especially in today’s diet culture, social media use and society’s pressure to be thin. Nonetheless, it’s important to know that these diets can be dangerous. In this post, we’ll take a look at some of the dangers of fad diets, and we’ll how to spot them in order to avoid falling in their trap. So if you’re thinking about trying a fad diet, read on –you might change your mind!

What is a fad diet?

Fad diets are eating plans that promise dramatic weight loss results and the answer to people’s problems. Most are not based on any type of proven evidence, do not provide long-term results and can be dangerous to health.
The dieting industry is a multi-billion dollar industry that succeeds by making people feel bad about themselves. People quickly become stuck in a vicious cycle of dieting –while the dieting companies make even more money!
Let’s check out the harmful effects of fad diets and why are fad diets dangerous.
What are the dangers of fad diets?
When it comes to fad diets, there are a number of dangers that need to be considered.
For one thing, these diets tend to be extremely restrictive and can lead to nutritional deficiencies over time. Our bodies need food in order to function properly. Food provides us with vital energy and nutrients. If we’re not getting enough of either, our health will suffer the consequences.
Additionally, many of these diets require extreme calorie restriction and elimination of entire food groups, which can result in undesirable side effects such as fatigue, mood swings, and weakness.
Furthermore, it’s pretty clear that these diets don’t provide any long-term health benefits, as the weight often tends to come back once someone goes off the diet. In fact, as many as 80 to 95% of dieters gain back the weight they’ve lost within a period of 1-5 years.
Ultimately, fad diets are not only unhealthy but also ineffective, and they contribute to body dissatisfaction and mental health problems.
What are the long term effects of fad diets
The long term effects of fad diets can be quite serious, as they often involve making drastic changes to one’s eating pattern and lifestyle.
These drastic and dangerous changes may lead to:
- Nutritional deficiencies
- Weight cycling
- Metabolic imbalance
- Engaging in risky behaviors, like excessive exercise or purging
- Development of eating disorders
- Aggravating a sense of failure
- Low self esteem
- Increased stress levels
- Heightening social anxiety
- Loss of self trust
- Poor body image
Over time, such extreme dieting can lead to deficiencies in certain vitamins and minerals, as well as other long-term health problems, like heart disease and digestive issues. Furthermore, the constant fluctuation in weight (weight cycling) not only puts strain on the body but also has an adverse effect on one’s mental health. Therefore, it is important for those considering a fad diet to carefully consider the long term risks involved before making any drastic dietary changes.
How to spot a fad diet

Fad diets are often characterized by extreme or restrictive eating plans, which can make them difficult to maintain in the long run. If you’re interested in avoiding falling into the fad diet trap, it’s important to learn how to spot them. Here are a few tips to help you out!
- Sounds too good to be true. If diets work so well, why are there so many of them?
- Promises fast results. For example, weight loss of more than “x” pounds per week . Drastic weight changes can be dangerous, can mess with your metabolism, and can also lead to weight cycling
- Eliminates specific foods and/or entire food groups. All foods/ food groups offer necessary nutrients. Unless you have a medical need to limit a certain food group, there is no reason to cut out an entire food group from your eating pattern
- Restricts calorie intake drastically. Calories are energy that your body needs. Restricting calorie intake too low will cause your body to enter into starvation mode. In this mode, your cognitive and physical processes are hindered and your metabolism slows down, leading to weight cycling and food bingeing.
- Labels foods as “Good” and “Bad”. The only “bad” foods out there are ones that are spoiled or will make you physically ill if you eat them. Although there are foods that are more nutrient-dense than others, restricting certain foods and labeling them as “bad” can lead to an unhealthy relationship with food.
- Promotes specific food combinations. There is no evidence that combining certain foods or eating foods at specific times of day will help with changes in your weight. Eating the “wrong” combinations of food doesn’t cause them to be stored immediately or to produce toxins in your intestines, as some plans claim
- Implies that body chemistry can be changed with food. Your metabolism and bodily processes are incredibly complex. Your body is hard wired to maintain a strict chemical balance, and eating a few specific foods is not going to override these processes any time soon.
- Promotes expensive “miracle” products. There is no magic diet pill, meal replacement smoothie, or elixir that will change your body size. These products often lack scientific evidence and are not proven to be effective.
- Encourages a rigid eating pattern. Eating in a way that prevents you from enjoying food and social situations is a huge red flag. Especially if a diet has you obsessing about food rules and is taking up a lot of mental space/ effort. Diets perpetuate and encourage disordered eating behaviors, which often leads to clinical eating disorders
- Based on anecdotal evidence/ before-and-after photos. Marketing around diets and dieting products do not have real science to back their claims. An effective eating pattern is one that is extensively studied and supported by sound, reliable research by credible professionals (for example, the DASH diet, the Mediterranean diet).
- Promoted by celebrities, individuals with limited/no sound nutrition credentials and/or salespeople. These endorsers get paid to advertise and sell you the diet. Influencers, celebrities and internet “health gurus” do not possess the necessary education, licensing credentials and/or regulation to provide nutrition advice
- Forces you to buy the company’s foods and/or supplements. By making you use their diet products instead of real food, this puts more money into the dieting industry and takes you further away from developing a healthy relationship with food.
- Based on a single study or misrepresented scientific studies. Just because a singular study concluded merit to a certain diet, does not mean it is so in every case. It is important to cross-check multiple studies, since scientific studies may be misrepresented by the media. It is important to examine all claims critically.
- Does not provide support for long-term success. Sustainable eating patterns are developed over time and built into lasting habits that you feel good about. A temporary “weight loss program” can definitely harm your relationship with food and erode body trust. It can also lead to metabolic damage that can make it harder to achieve weight stability in the future.
Fad diets examples
As we can see, the dangers of dieting/fad diets are very serious. Here are 3 examples of the most some popular fad diets today, and why they can be dangerous to your health:
- Keto diet for weight loss. The keto diet is difficult to follow, there is no evidence of its long-term effectiveness and safety, and it restricts important food groups
- Intermittent fasting. Intermittent fasting is a predetermined period where an individual purposely doesn’t eat food. This can vary from a 12-hour fast to alternate day fasting, to many other variations in between. This type of popular fad diet can drive binge eating after the fast is over, a negative relationship with food and disconnection from your own hunger signals
- Paleo diet. Although the Paleo diet does promote the consumption of foods such as fruits and vegetables, which are vital for health, it also eliminates entire food groups that have important nutrients. Furthermore, there is a lack of scientific evidence to support the long-term effectiveness and safety of this diet. Lastly, just like any other fad diet, the Paleo diet can also be difficult to stick to and increases your risk of eating disorders by being so hyper-focused on what you can and can’t eat.
Conclusion
So, what have we learned? Fad diets are dangerous and can have long term negative effects on your health. They are often promoted by people with no nutritional training or expertise, so it’s important to be able to spot a fad diet before you fall for its tricks. If you think you might be struggling with an unhealthy relationship to food, please seek professional help. You can always schedule a FREE 15 minute discovery call with me right here.
Remember that there is no “one size fits all” approach to nutrition – the best way to find out what works for you is to explore and listen to your own body. What has been your experience with the dangers of fad diets?

Hi! I’m Melissa, Registered Dietitian and mother of two dragons. When I’m not talking nutrition you can find me rolling around the floor with my kids, sewing, crafting, cooking or missing the 90s (seriously, music just isn’t the same). Read More…