MV/FIT Movement Fitness

The Truth About The 800 Calorie Diet


The jury is out on 800 calorie diets and it is not good news for the highly popular and mass marketed diet.   

In this "truth about", I will dive into the detail about what an 800 calorie diet is and hopefully shed some light on the dangers of reducing your calories this low.

So what is an 800 calorie diet?

An 800 calorie diet, is quite simply an ultra low calorie diet. This type of diet is sometimes considered for obese and severely obese people as a way to manage their diabetes. It is also sometimes advised for people about to have surgery.   

The NHS website is quite clear that these "very low calorie diets should only be followed if recommended by your GP". Further to that, "it should only be followed for a maximum of 12 weeks" and it is necessary to be "under medical supervision."   

To me that sounds a lot like a public health warning. So why is it that so many people are talking about it and wanting to follow this diet?   

As a Personal Trainer, people often ask me if they should reduce their calorie intake to 800 calories a day.   

My answer, is to give them the calorie needs and requirements of a child aged between 2-3 years old.   

The answer is 1000 - 1400 calories per day!   

If that isn't enough to deter them from it then I am positive that listing the common side effects of ultra low calorie diets will.   

Sneak peak: it's quite startling.   

Common side effects can include:   

 -    a dry mouth 

 -    constipation or diarrhoea 

 -    headaches 

 -    dizziness 

 -    cramps 

 -    hair thinning 

 -    Plus, the obvious symptoms such as feeling hungry & lacking energy.    

Once you understand the severity of these side effects, most people realise that this is not conducive to good health and quickly scrap the idea of ever wanting to reduce their calories this low.   

Interestingly, the above side effects are just the tip of the ice-berg in terms of the serious health consequences for your body.   

Other major issues can include:   

  •  An increased risk of illness   

 You are not providing your body with enough energy and nutrients to function; therefore, it can negatively impact your immune system and you are more likely to become ill.   

  •  Nutrient deficiencies 

 It is difficult (read: practically impossible) to meet your nutrient requirement eating just 800 calories per day. So, it is likely you are not going to be achieving your recommended daily intake of vitamins, minerals, protein, fats and carbohydrates, fibre and much more.   

  •  Likely to regain weight plus interest   

 Know one wants to lose 1 stone and regain 1.5 stone after finishing your diet. Therefore, an 800 calorie diet is not a sustainable fat loss strategy for the long term.   

  •  It could weaken your bone density   

 If you are not meeting your recommended intake of nutrients, it is likely that your bone density could weaken as your body tries to access nutrients and energy it can.   

  • It could lead to an unhealthy relationship with your food & potential eating disorders   

 An ultra low calorie diet can often worsen your relationship with food. It is quite common for people to become scared of eating higher calorie foods or just eating in general. This is not a positive thing and something I feel is the biggest risk factor with ultra low calorie diets.   

In summary, ultra low calorie diets are simply not a viable option for a significant portion of the population. They are not healthy, they are not a long term fat loss strategy and they can cause a whole host of negative consequences.

How do we help our clients with their nutrition?

We believe in an evidenced-based nutrition system here at MV / FIT. We focus on improving nutrition habits and behaviours, over fad diets that don't work in the long term. We highly value consistency and working with our members closely to achieve their body composition and health goals. We aim not to restrict, but to give our members options and methods which they can apply to their own diet to improve it from the ground up. We use methods such as the portion control method to help our members understand how much of each nutrient they need - this allows them flexibility in their food choices which in the long term leads to better adherence and enhanced results. 

- Coach Alex

*Disclaimer: This blog is only intended for information purposes only. This does not constitute medical or health advice. 

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