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Do Fad Diets Work?

Fad diets often promote quick weight loss through drastic caloric restriction, elimination of entire food groups, or excessive focus on one type of food. This can lead to nutrient deficiencies, slow metabolism, and eventually weight regain. Additionally, they are often not sustainable long-term, and do not address the root causes of unhealthy eating habits.

Fad diets for weight loss often fail for several reasons:

  • Restrictive nature: Most diets restrict certain foods or entire food groups, making them difficult to follow long-term.

  • Lack of sustainability: Rapid weight loss from diets is often not sustainable, and people tend to gain the weight back once they return to their normal eating habits.

  • Metabolic adaptation: Drastic caloric restriction can slow down metabolism, making it harder for the body to burn calories and lose weight.

  • Not addressing the root causes: Diets treat the symptoms of poor eating habits rather than addressing the underlying psychological and behavioural issues that contribute to them.

  • Focusing on weight rather than health: The primary focus on weight rather than overall health can lead to a negative relationship with food and body image.

Additionally, extreme diets can disrupt the balance of hormones such as leptin and ghrelin that regulate hunger and fullness, causing a person to experience cravings, feel constantly hungry and lead to binge eating or overeating. Also, when the body is in a calorie-deficit, it may break down muscle tissue for energy, resulting in loss of muscle mass, which slows down the metabolism further.

Furthermore, the composition of gut bacteria can change in response to changes in diet, potentially affecting digestion, metabolism, and other aspects of health. It is important to note though, that this biological adaptation can vary greatly depending on the type and duration of the diet, as well as individual differences in genetics, metabolism, and lifestyle.

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Source: OSU The Health Risks of Fad Diets

A common scenario with dieting is trying to restrict caloric intake to lose weight, often by cutting out certain foods, limiting portion sizes, or following a specific diet plan. However, many people struggle with sticking to their diet plan long-term, and may experience feelings of deprivation, cravings, and difficulties maintaining the diet in social situations. As a result, they may experience weight loss, followed by weight regain, a pattern commonly referred to as "yo-yo dieting."

Consequently, many dieters believe that they are not “good at dieting” and fail the diet, whereas THE TRUTH IS THAT THE DIET FAILS THEM due to all reasons outlined above. Therefore, a personalised approach which takes individual characteristics into account and helps to establish a health-promoting and meaningful long-term relationship with food, activity, and one’s body is the key to success.

Want to get on top of your health and receive further guidance? Book in with Irina, our diet and disordered eating specialist today to discuss your concerns in a commitment free call.


Irina Pollastri

Registered Nutritional Therapist


Irina has a special interest in eating disorders and disordered eating, such as binge eating, bulimia, chronic dieting, restrictive eating, emotional eating, and poor relationship with food in general. To provide support in these areas and any co-occurring health conditions, Irina offers a personalised approach, which combines nutritional, behavioural, and psychological interventions.

I am not attempting to prevent, treat or cure any physical, mental or emotional issues. Do not disregard medical advice or delay seeking medical advice because of information you have read on this website. Do not start or stop taking any medications without speaking to your primary health care provider.


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