Crash Diets

Dishonesty when it comes to nutrition in the fitness industry is the one thing that really grinds my gears. I can’t scroll down my Facebook or Instagram feeds without seeing an ad or a post of a diet promising to rid you of a significant amount of pounds in a very short amount of time. The problem is that they don’t work long-term, they promote weight regain and will make you gain more weight than when you started the diet.


I will try to keep my explanation simple. To lose weight, you need to be in a calorie deficit (burning more calories than you’re taking in). That’s easy. But, these ‘crash diets’ all have the same premise: they have you eating at a major calorie deficit and this is where the problem lies. Anyone can drop a lot of initial weight by eating 600-800 calories per day, but is that going to be sustainable? Even if you were a hobbit and somehow managed to remain at such a major deficit for a longer period of time, your body will fight you every step of the way. Your body wants to achieve homeostasis, which basically means it doesn’t want to be consuming too little calories and wants to maintain a weight where it is comfortable.

When your body is fighting back, it will reduce metabolism, so you won’t burn as many calories as before. Your body will also become a fat-storing machine as it goes into ‘survival mode’. Additionally, your body will adjust your hunger hormones to make you feel more hungry and less satiated, so you’re more likely to over-consume calories. Now, with the combination of your body being prone to fat storage, your increased hunger and decreased satiety levels, it is just a matter of time before fat gain increases rapidly. This is because it’s impossible to remain at such a major calorie deficit day after day for the rest of your life.

The best diet is the one that you can still see yourself on 5-10 years from now, or better yet, forever. Crash diets, cleanses, or diets that restrict a whole macronutrient group (such as Atkins or Ketogenic) will probably make you lose some weight initially (because you’re in a calorie deficit), but unless you’re going to follow them forever you will be prone to fat regain when you go back to eating normally. This is why I use Flexible Dieting or IIFYM (If It Fits Your Macros) for myself and my clients whereby you are accounting for the nutritional content in the foods you are consuming (while also meeting some daily nutritional requirements) to hit your individualized targets. You can refer to my last blog post which goes into more detail about Flexible Dieting.

Do you want to work together to reach your body composition goals? Or just have a question? Don’t hesitate to contact me at