Carbs, calories and weight loss explained

I have had quite a few questions lately on calories and carbohydrates. There seems to be some confusion on what the most important factor for weight loss is.

Let me try to explain for you here. (I hope I can keep it simple)


Burning up more calories than we need (to maintain weight) is how we lose weight. 

calorie deficit

When I say “how we lose weight”, I mean that it is the ONLY way we lose weight. There are many “methods” to achieve this outcome, but you must arrive at a calorie deficit in order for weight loss to happen.

The lost “weight” (as measured on a scale) comes from either our…

  • stored body fat (Yay)
  • or
  • lean muscle (Boo),
  • or sometimes a combination of both.


 Let’s look at Sally and Betty.

(Gee I pick on poor Sally and Betty a lot)


Let’s assume for argument sake that Sally and Betty are twin sisters. They are the same height, weight, age (obviously)  and they both want to lose weight.

Sally and Betty type their weight, age and activity etc. into a calorie calculator.

It tells them both that they need to consume 2300 calories per day to maintain their current weight.  (Calorie calculators give a rough estimate, not an exact number, please don’t get super obsessive about this)

They want to lose weight, so they decide to eat 1800 calories per day (500 calorie deficit).

They also commit to burn up an extra 500 calories, by increasing their daily exercise / movement. This should result in them losing approx. 1kg per week.

Please also see a detailed post on this “How to lose 1kg per week. A step by step guide”


Ok, so Sally and Betty now have a rough calorie “budget” to work with. Consider this step number 1. (Quantity of calories)

Next let’s look at what food choices go into that 1800 calorie budget (Quality of calories and macro-nutrients)


Sally chooses foods that contain mostly carbohydrates. 

Rice crackers, low fat muesli bars, low fat yoghurt, fruit, fruit juice, salad sandwiches on whole grain breads, healthy breakfast cereals etc.

Sally is so happy with herself. She has stuck to her 1800 calorie budget and she has chosen low fat, healthy food. She cant wait for her awesome weight loss transformation.


Betty makes sure she eats one handful of a protein rich food at each meal, a handful of carbohydrate rich food and lots of vegetables.

When Betty adds it up, the protein and vegetables she eats each day  makes up about 700 – 800 of her calorie budget. The remainder of her 1800 calorie budget is made up of carbohydrate rich foods and healthy fats.

Betty’s plan naturally limits the amount of carbohydrates that she consumes, compared to Sally’s. Not because carbs are evil or bad (or any other scary word), simply because she has prioritised protein and vegetables first. Betty’s plan is not what you would call “low carb”, she can actually fit a lot of carbohydrate rich food into her diet if she checks labels and is aware how many carbohydrates are in her favourite foods.

You might also like to read my little rant on hidden sugars here.

** Please note this very important factor.

Sally and Betty both eat exactly the same amount of calories (1800) IN and lets assume for arguments sake that they both burn up the same amount of calories OUT each day too.

Same amount of calories IN.

Same amount of calories OUT.  (Quantity)

Different macro-nutrient make up. (Quality)


What happens next?

Yay, they both lose weight over the next 8 weeks.

Duh !!  Of course they do. They are both in a CALORIE DEFICIT and that’s how all weight loss works.


Sally loses 7 kg (on the scale)

Breakdown of Sally’s weight loss

  • Lost 4kg of body fat (Yay)
  • Lost 1kg of fluid (this is pretty normal)
  • Lost 2kg of precious muscle (BOO)

Sally didn’t eat enough protein. 

Protein is what builds and maintains our muscles (along with doing some resistance training of course). Not getting enough protein usually results in some of the lost weight coming from precious muscle.

Lost muscle means that Sally’s metabolism will go down slightly and that she will look smaller, but flabbier too.

An added bonus of eating protein is that it will keep you full for longer. And yet another bonus –  Protein is high in thermic effect too, meaning that some of the calories that you eat will be used up in the digestions process. You can read more about that here.


Betty loses 8kg (on the scale)

(she loses slightly more because of the high thermic effect of the protein and veg)

Breakdown of Betty’s weight loss

  • Lost 8kg of body fat (double the amount that Sally lost)
  • Lost 1kg of fluid
  • Put on 1kg of muscle (she happened to be doing some resistance work too)

Betty consumed enough protein.

Most of the weight Betty lost came from body fat. She preserved her precious lean muscle. Betty’s metabolism didn’t go down as much as Sally’s and you can even see some nice firm muscle definition showing now that the extra layer of body fat is reduced. I am not talking body building standards, just a nice firm shapely figure.


Side note – Getting enough protein and veg whilst consuming small portions of carb each meal is also a great way of managing your blood sugar and insulin levels during your day. Which in turn manages some of your fat burning hormones, which can make fat burning easier. We discuss this in full in my fat loss coaching program.Coaching with Chriss for long term health and weight loss success


One last important note.

This does not mean that you have to strictly count every last calorie that goes into your mouth (unless you want to). I don’t count calories and neither do most of my clients.

For the average person who does not need to make a specific low level of body fat for a competition or career, 90% of this can be achieved by following these simple rules…

  1. Choosing most meals (including snacks) with 1 palm size of a protein rich food, 1 handful of carb rich food  and lots of salad / vegetables.  (Yes, I do realise that salad and veg contain carbohydrates, but they are so high in fibre, water content and thermic effect that I a giving them their own category).
  2. Only eating when “fairly hungry” and stopping when satisfied, not full.
  3. Become calorie aware of your needs and how much is contained in the foods you eat

Strictly counting calories and macro-nutrients may be necessary if

  • these above 3 steps do not work for you,
  • if you aim to get REALLY lean for some sort of physical competition goal,
  • if you just love the structure of rigid rules.


Want more help with your fitness and fat loss goals?

Find out how I can help you HERE – Work with me


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