Extreme Diets: Exploring the Pros and Cons

What diet is best? In this post we dive in to the different types of diets seen today, the pros and cons of each. As well as some information regarding our own approach we provide our clients.

The world of dieting is vast and varied, with new trends emerging regularly. In this blog post, we’ll explore some of the most popular extreme diets, including the ketogenic diet, intermittent fasting, Paleo and raw foods diet. We’ll also delve into our own method, calorie counting and how it can lead to mindful eating for sustainable health benefits.

The Ketogenic Diet: High Fat, Low Carb

The ketogenic diet, commonly known as the keto diet, is a high-fat, low-carbohydrate diet that has gained immense popularity. The goal of the diet is to induce a state of ketosis, where the body burns fat for fuel instead of carbohydrates. This diet includes a significant reduction in carb intake and a relative increase in fat consumption.

image of a diet pyramid, Extreme Diets: Exploring the Pros and Cons

Pros of the Ketogenic Diet

1. Weight Loss: Studies have shown that the ketogenic diet can lead to significant weight loss. A study published in the journal “Obesity Reviews” found that participants on a ketogenic diet lost more weight compared to those on low-fat diets.

2. Improved Blood Sugar Control: For individuals with type 2 diabetes, the ketogenic diet can improve blood sugar control, as reported in a study in the “Journal of Nutrition and Metabolism.”

Cons of the Ketogenic Diet

1. Nutrient Deficiencies: Due to the restrictive nature of the diet, there’s a risk of nutrient deficiencies, particularly in fiber, vitamins, and minerals. We are not sure whether avoiding fruits and many vegetables that contain carbohydrates is beneficial long term for anyone, as our diet should be a large variety of foods to ensure we do not miss out on anything.

2. Difficulty in Sustaining: The diet is hard to maintain long-term due to its restrictive nature. Many people will use this diet in order to lose weight, however, they crave carbohydrates at some point and may destroy their progress by snacking on them occasionally ( defeating the purpose of the diet) or rebounding when they come off the diet, overdosing (per say) on carbohydrates that they have been denied for so long.

Intermittent Fasting: Eating in Time Windows

Intermittent fasting involves cycling between periods of eating and fasting. Common methods include the 16/8 method (fasting for 16 hours and eating during an 8-hour window) and the 5:2 method (eating normally for five days and restricting calories for two non-consecutive days). There are a whole bunch of different fasting and eating windows, most commonly, people will pick a window that suits their schedule the best.

Pros of Intermittent Fasting

1. Weight Loss and Metabolic Health: Research suggests intermittent fasting can aid in weight loss and improve metabolic health. A study in the “American Journal of Clinical Nutrition” found that intermittent fasting can reduce body weight and improve metabolic health markers.

2. Convenience: It can be easier to follow than diets that require constant calorie counting or food restrictions.

Cons of Intermittent Fasting

1. Hunger and Fatigue: Fasting periods can lead to increased hunger, irritability, and fatigue, especially in the initial stages. 

2. Over-eating: Although people are restricted from eating for large periods of time, this does not mean that the laws of thermodynamics do not apply to them. If you over eat during your eating window, you will gain weight, regardless of how long you have fasted for. We have seen countless people binge eat as soon as they have done fasting as they think this is a sign that they are allowed to do so given their long periods of restriction, in doing so they will eat way more than needed to satiate their hunger, often leading to weight gain.

The Paleo Diet: Back to the Stone Age

The Paleo Diet focuses on consuming foods that were presumably eaten by early humans, such as meats, fish, fruits, vegetables, nuts, and seeds, and avoiding processed foods, grains, and dairy.


1. Elimination of Processed Foods: By focusing on whole foods, the Paleo Diet eliminates many processed and refined foods, which can be beneficial for health.

2. Weight Loss: Some people may experience weight loss due to the diet’s emphasis on whole foods and protein intake. If someone has issues with controlling their appetite around certain foods (for example: ice cream and chocolate) having the option to cut those foods out of the diet completely might be beneficial for them, and in turn, lead them to be in a calorie deficit due to the control placed on their eating habits.


1. Nutritional Imbalances: The exclusion of whole grains, legumes, and dairy can lead to deficiencies in certain nutrients like calcium and fiber. Additionally, the evidence surrounding what humans ate exactly back in the times this type of diet was supposed to be present is variable, as humans ate what was available to them depending on their location, there is no exactly similar way of eating pre-historic humans adhered to.

2. Sustainability Issues: The diet can be expensive and challenging to maintain long-term. Plus, who doesn’t want some ice cream now and then?

The Raw Food Diet: Uncooked and Unprocessed

This diet involves consuming mainly uncooked and unprocessed plant-based foods. The belief is that cooking food destroys its nutrients and natural enzymes.This is an extension to some degree of the Paleo diet and probably the least appetising.


1. High in Nutrients: Raw food diets are typically rich in fruits and vegetables, providing plenty of vitamins, minerals, and antioxidants.

2. Weight Loss: Due to its low-calorie nature, this diet can lead to weight loss. Many people find it very hard to overeat on this type of diet, as the food they eat are not as appetising compared to cooked or processed foods of the modern day. 


1. Nutrient Deficiencies: Strict raw food diets can lead to deficiencies in protein, iron, calcium, and other essential nutrients.

2. Foodborne Illnesses: There’s an increased risk of foodborne illnesses due to the consumption of uncooked foods. Many foods must be cooked to be consumed and people run the risk of severe illness of not cooking them!

Our Approach: Calorie Counting and Mindful Eating, A Sustainable Approach

Calorie counting involves tracking the number of calories consumed and burned to achieve weight loss. While effective for some, it can be tedious and lead to an unhealthy focus on numbers rather than food quality. In saying this, calorie counting is the method we initially are proponents for many of our clients. Doing so will teach them nutritional literacy so they can better understand what is in the food they are eating and whether or not they are making smart choices based on their goals. Once the individual has progressed in their fitness endeavors and their diet reflects the goals they are trying to achieve, we will usually pivot the individual toward portion control and mindful eating, removing the need to count calories based on their newly learnt nutritional literacy during their time tracking.

Transitioning to Mindful Eating

Mindful eating is about being present during meals, paying attention to hunger and fullness cues, and enjoying the flavors and textures of food. It’s a sustainable approach that promotes a healthy relationship with food. After the individual has gained enough knowledge and understanding regarding the foods they are eating, we are proponents of shifting toward a mindful eating approach, as we do not believe one must count calories forever. 

1. Promotes Intuitive Eating: Mindful eating encourages listening to the body’s hunger signals and eating accordingly, which can lead to healthier eating habits.

2. Reduces Stress Around Food: By focusing on the experience of eating and enjoyment of food, mindful eating reduces stress and anxiety related to dieting and is a more long-term approach

In conclusion, while extreme diets can offer quick results, they often come with drawbacks, including potential nutrient deficiencies, difficulty in sustaining, and health risks for certain individuals. In addition to this, all of these diets must adhere to the laws of energy balance. If you are losing or gaining weight when using any of these diets, it will be because you are in a calorie surplus/deficit, not because of the diet itself. The diet is merely a vehicle in getting you to your goal, but does not do anything different in terms of energy balance that eating a regular diet would. 

Here at Performance United – Sans Souci, we are not proponents of any particular dieting style. We teach our clients the role of food and how calories consumed work within the body depending on their goal. Calorie counting is the easiest way to do this, as it requires the individual to track everything they eat for some time to ensure they are on track with their goals. Doing so will both educate and leave less margin for error, while offering a pivot toward a more sustainable approach. Once the client has shown the ability to track calories, understanding and is progressing, we will switch to the mindful eating approach. Which may provide a sustainable and healthy way to manage weight and improve overall well-being. This type of diet strategy utilized the clients newly found knowledge of calorie intake, portion control, and energy balance to better understand how food can affect both their weight and performance. 

Remember, it’s always important to consult with a healthcare professional before starting any new diet or eating plan. This post is not medical advice.



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