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Why Calories In Vs Calories Out isn't the whole picture

A calorie is not just a calorie. If it were, I wouldn’t have multiple clients coming to me eating the same amount sufficient to fuel a toddler yet still in a body larger than they would like and unable to shift that weight.


Food is more than just energy. Yes, food is energy but it is also composed of different nutrients, vitamins, minerals and in the case of processed food - chemicals. Food is information that speaks to your body and impacts:

  • Gut microbes - which have a direct impact on your metabolism, cravings and energy

  • Gene expression – whether certain genes are turned on or off - like genes that increase the tendency for the body to hold onto weight

  • Mood through impacting the production of brain chemicals like dopamine & serotonin, which in turn impacts someone's motivation to follow through with the behaviour change necessary to achieve their health goals

  • Stress levels - inflammatory compounds in food cause stress on the body, as does eating too little, which causes excess cortisol production and impedes weight loss

  • Thyroid function and metabolism

  • Blood sugar control and cravings

  • Hunger hormones – whether you feel satiated by the food or hungry soon after


I had a client just the other day who's immune system is down and her gut health has been poor ever since being on a long-term very low-calorie diet (around 900 calories per day), which, although helped her to lose weight at the time, has caused more health problems for her moving forward.


If you are eating a calorie deficit and losing weight but your energy is shit, your sleep is shit and your mood and stress tolerance are shit, then take a second to think if the food that makes up the calories that you are eating is serving you?

I don’t like calorie counting for most people as your body is not a calculator and food means far more to it than energy alone. In some cases if a client has limited knowledge about energy in food and is continuously eating a calorie surplus without realising it then it can be a helpful tool, when used appropriately and for educational purposes.


Individuals who currently calorie count or have done so in the past are likely to have a strained relationship with food and a disconnection from true feelings of hunger. It is not natural for humans to treat food like it is just energy and macronutrients when it is so much more.


Here is a comparison between a fillet of salmon and a bowl of corn flakes to highlight why calories are not all that matters when it comes to weight loss and overall health.

*the below values are based off 175g of salmon and 30g of corn flakes with 125mL of skim milk*

The salmon fillet, whilst higher in total calories, is high in protein, healthy fats, vitamin D, potassium and selenium and is going to support energy levels, stable blood sugar levels, mood, hormones, have an anti-inflammatory effect on the body and keep you full for hours. The bowl of corn flakes, whilst lower in calories, is predominantly made up of carbohydrates and sugar which will send your blood sugar level sky rocketing and leave you hungry and tired in an hour, craving another sugar fix.


Which one do you think is healthier for you and will lead to weight loss in the long run?


A healthy body will naturally come to a weight that is healthy for it in time and this looks different for everybody

Research shows that 0.5kg per week is a sustainable and healthy rate of weight loss and weight loss that is faster than this can have negative impacts on your metabolism and gut health. I find that centering your short-term goals around achieving better energy levels, sleep, and stress tolerance is far more satisfying and healthier than weight loss alone.



My top tips for healthy and sustainable weight loss include:


  1. Eat enough protein – this equates to 1.2g-2g per kg of bodyweight per day, depending on your activity level.

  2. Stay hydrated – your body can confuse feelings of thirst with hunger – so if you feel hungry all the time and you are eating enough protein ^ then you may be thirsty. On average, females need around 2L, and males need around 2.5L of water per day to stay hydrated.

  3. Get 8 hours of restful sleep per night – there is a very close link between weight and sleeping patterns.

  4. Manage stress levels - elevated cortisol is one of the main things I see impeding weight loss as we are in an epidemic of high stress

  5. Exercise most days – not only does exercise help to increase your energy output but it has positive effects on blood sugar levels and metabolism. Anything is better than nothing when it comes to exercise. Find some things you enjoy and do them often

  6. Eat whole foods and minimise packaged foods – focus on vegetables, good quality meat, eggs, and some fruit for 80% of your food intake



Weight loss is a different journey for everyone, despite the mainstream view that you just need to exercise more a eat less. If you are wanting individualised support to shift stubborn weight in a way that is sustainable and healthy, please book in a 15 minute complimentary consultation with me and we can discuss further.


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