Why the one-size-fits-all approach to dieting won’t help you lose weight

...and the factors that will

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Ask 20 people to eat the same diet for 10 weeks and you’ll get 20 different results, despite everyone being under the same controlled conditions. This shouldn’t really be surprising. If we put 20 people in an environment where they are all taught to play a musical instrument, we wouldn’t expect all of them to be playing at the same level, even after the same amount of tuition. We’re all different, biologically, physically, emotionally and genetically.

One size does not fit all

With that in mind, why do we still sign up to diets that follow the ‘one-size-fits-all’ approach? Wouldn’t it make more sense to personalise what we do, in terms of both diet and exercise? Here are other factors that you should be thinking of when personalising your diet.

The over-simplification of ‘eat less and move more’

What we understand about weight loss and calorie management has changed dramatically over the last few years, although this information is slow to filter down, in part due to media reporting and advertising. We are still recovering from the brainwashing we received in the 1970s about fat being the source of all our weight problems, leaving us thinking it’s the macronutrient to be avoided at all costs. (Check out my recent podcast on this very topic). What scientists are now discovering about why some of us struggle with our weight, blows the ‘eat less and move more’ and fat demonisation theories out of the water. Here’s why.

It’s in your genes

Scientists now understand that how we respond to basic nutrition relies a good deal on our genetics. Dr. Claude Bouchard, faculty fellow at the Texas A&M University, says “the response to environmental, social and behavioural factors is conditioned on the genotype of an individual. Your adaptation to a diet or a given amount of exercise is determined by your genes.”

It is believed that one day medical treatments will be created bespoke for us according to our genetic make-up, and it has been possible for a few years now to buy a DNA test which tells you the best type of exercise for you and your ideal diet type. Other factors such as your gastro-intestinal health and the microflora in your gut also have a profound impact on how you process food, absorb micronutrients and store fat.

The obesogenicity of the environment

The term ‘obesegenicity’ is the term used to describe how the environment contributes to obesity. In the West, our environment is set up to be as efficient as possible; we have multi-transport systems which remove the need for walking; we have fewer outdoor spaces and fewer pavements; there are fast food outlets everywhere, usually rich in refined carbohydrates; many of our jobs are now desk-bound; we have labour-saving devices which minimise our need to move; our food shopping can be ordered online and delivered straight to our kitchens; our factories and machines emit toxic gases and pollutants which disrupt our hormone profile and in turn can affect our weight.

Social factors

It’s become commonplace to prioritise price over provenance with foods, and we end up eating cheap foods that are not as nutritious. Many of us are now used to eating on the run or in front of the TV, and consume processed foods because they’re quick to prepare. We’re losing the love of home cooking and all because it just takes a bit of time. We need to value our health enough to spend that extra half-hour on a meal. Society has also normalised outsize portions – fast food and drinks sizes have risen year on year.

Behavioural factors

Linked with social factors, there are a number of behavioural factors that affect weight management. We are now more sedentary, and less disposed to walk than we once were. We have become more reliant on transport and labour-saving devices. Many of us have a powerful cognitive dissonance, so even though we know we should move more, or perhaps leave the train a few stops earlier and walk the rest of the way, we don’t. We often drink more alcohol than we should, or postpone the visit to the gym, even though we know we should be doing it. There is an increasing reliance on medications now too which can have an impact on weight. Our decision to take these medicines affects how we store fat and burn energy.

There are so many factors which influence body composition, and the clever money is on applying the broad principles of ‘move more’ with personalisation. What worked for your friend may not work for you – because everyone is different. Make it about you. Make it personal. If you’d like our help with that, just get in touch or take our Health IQ test and book your free 30-minute Discovery Session today.

What’s your Health IQ?

If you’re reading this, you’re are probably in a reasonably senior position, running your own business or have a busy life running the home and juggling other responsibilities. Either way, you’re busy. The convergent pressures of work and family life have probably meant that the time you did have to spend on health and fitness has disappeared. Why not talk to us and see how we can help.

Click here to take our test

Leanne Spencer is an entrepreneur, coach, TEDx Speaker, author of Remove the Guesswork, and founder of Bodyshot Performance Limited. Bodyshot is a health and fitness consultancy that helps busy professionals get more energy by removing the guesswork around their health, fitness and nutrition. Visit or email [email protected] to register your interest in our services and connect with us on Facebook, Instagram and Twitter.

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