If calories are king.. why does it matter what I eat?

How much does it matter how you lose weight?

If calories are king why does it matter what my macros are? Or, in other words; If calories are king why does the composition of my diet matter?

There are 2 main reasons (..or possibly just 1 absolute reason):

1) Essential nutrients

You NEED certain essential amino acids that make up protein and essential fatty acids that make up fat from your diet as your body cannot synthesise these. You also need a supply of vitamins and minerals for your body to function. A varied diet that includes fat, protein, vitamins and minerals gives your body the nutrients it needs to survive and maintain health.

2) Satiety and adherence

You will struggle to stick to a diet that isn’t well balanced.. this is a much lesser point than the first one as people can and do stick to very restrictive diets e.g very low carbohydrate diets, vegan diets or keto diets. However, these diets do have a higher occurrence of deficiencies and if you did decide to follow these you should consider supplementing with nutrients you may be missing. E.g. vitamin b12, calcium, iron and zinc in vegetarians and vegans.

Now I am side tracking back to my original point.. maybe there is only one real reason but my point here is it probably isn’t enjoyable or maintainable for most people to stick to restrictive diets that cut out large parts of a balanced diet long term. Once you have accounted for essential levels of fat, protein and (I would suggest) fibre the rest is up to you/preference.

Note that you will probably have at least some carbs if you meet a decent fibre amount and do not want to rely solely on supplements for vitamins and minerals. You can and will lose weight in an energy deficit no matter what your diet’s macro nutrient composition is.

In fact, we probably over play our need for a ‘healthy’ diet to maintain health. Especially in those who have a lot of fat to lose. Their loss of fat is going to improve their health to a bigger extent than any slight deficiencies they may or may not encounter.

Examples of this include:

The obese man who fasted for over a year, experienced no ill health and only took vitamin and potassium supplements.

And more recently..

The man who went on a convenience store diet AKA the twinkie diet and experienced an improvement in health markers due to his fat loss despite the fact his diet would be classes as ‘unhealthy’ and lacking in nutrients. In fact, Twinkie diet man lost 27lbs in 10 weeks and more importantly his health markers including cholesterol and blood glucose levels improved.

Note that he also took a multivitamin and protein shake and as well as occasional canned veg.

One more example is the Newcastle diet which puts overweight, type 2 diabetics on a very low calorie diet of just 600 calories a day made up largely of a high protein, high sugar meal replacement shake and a salad.
This diet has consistently shown the ability to reverse type 2 diabetes by reducing fat around the pancreas and liver and restoring normal glucose control (more on this here).

Although I am in no way suggesting the diet above I think it is a useful observation and proves the point that if you have a lot of fat to lose fat loss has more benefits to health than diet composition per se. i.e

“When you lose fat, regardless of how you’re doing it — even if it’s with packaged foods, generally you will see important health markers improve.

To conclude:

Although most would assume that eating twinkies to lose weight is unhealthy the data don’t seem to support that. It seems to be the overall fat loss that is the biggest predictor of health.  

Stop being so anal about your calorie goal

Stop being so anal about your calorie goal

It is an estimate and should be treated as such.



Your expenditure will vary day to day


Your intake will vary day to day.

That means to maintain the exact same energy deficit day to day you would have to change your calories daily based on any changes in behaviour.. not only would this be insanely anal and unnecessary but we simply do not have the technology to do so accurately.

The importance of your specific calorie goal should not be over emphasised. If you need proof of this concept look at all the diets that work that don’t involve counting calories..  low carb, low fat, 5:2.

You do not NEED to count calories. Doing so is a sensible approach especially initially to gauge how much you should eat or if/when your fat loss stalls.

I do feel many of us have become too analytical and caught up on the numbers. There are so many chances for errors to creep in that worrying about precise calorie intake or expenditure and religiously following that is senseless.

Let’s have a look at where errors creep in..

– Your total daily energy expenditure (TDEE) is an educated guess.
TDEE is calculated using an equation based on your current weight and activity levels. So in terms of accuracy we are already off to a bad start at the first hurdle.

– Your fitbit/Activity tracker is not accurate so if you are using it under the illusion you are tracking your expenditure precisely, well, I am afraid you’re not.
That’s not to say it is not extremely useful for increasing activity levels and staying accountable to how much you do (or don’t) move.

– Myfitnesspal is not accurate.. SHUT THE FRONT DOOR.
Portion sizes vary.. one chicken breast is not always the same size. Even if you are weighing foods there are inaccuracies. Not to mention the fact MFP is an open resource and anyone can put in nutritional info.

– Restaurant calorie info is inexact.
Again, portion sizes vary, cooking methods vary, fat added varies.  Restaurants aim to make tasty food..they don’t care much about calories.

Your day to day activity levels vary.

Decide to take the lift instead of the stairs? There’s 20 less calories used. Helped an old lady up the steep hill to her house with 5 bags of shopping? There’s 50 more calories burned. Boiler broken and you’re sitting in the cold all day? An extra 80 calories keeping warm.

  • Some Advise:

    If weight loss is the goal focus on being in a net deficit by the end of the week and not obsessing over 20 calories here and there.

    Having a calorie target is useful but there is no need to obsess over it to the exact calories..

    If weight loss is your goal always err on the side of lower calories and if weight gain is your goal always err on the side of more calories.

  • Make sure the size of your deficit relates to your goal. E.g. if 1lb a week fat loss is a good goal for you (this will depend on the amount of fat you have to lose and any time restraint) then you will want to aim for a deficit of 3,500 calories a week (1lb of fat = 3,500 calories).

    *Note: weight loss is not linear and the scales will sometimes mask weight loss.