Calories, Macros or ‘Quality’?

By Cliff Harvey ND, Dip.Fit, PhD (c)

A common debate in nutrition is what’s most important, calories, macros, or ‘quality’ of the food we eat?

On balance, I’d have to say that for most people, most of the time, calories are king!  Now before you spit up your kombucha and deride me daring to play on the ‘calories in calories out’ team, hear me out…

The first law of thermodynamics is immutable, and you just can’t get around it!  When you supply more energy to a system and that energy is not expended it will have to be stored. Similarly, if you expend more energy than you’re taking in, stored (potential) energy will be released for use. That’s why, no matter what you’re eating, if you eat fewer calories than you expend overall, you’ll lose weight and typically lose fat.

BUT the way we achieve calorie balance is perhaps more informative to what we actually have to do in nutrition. And this perhaps is the reason why we have the debate.

The key considerations are substrate end-points (i.e. where is the fuel component likely to end up), dietary induced thermogenesis (DIT), the effect of macronutrients on satiety and whether enough micronutrients (the ‘little guys’ like vitamins and minerals) are being provided.

Substrate end-points

Really, this concept describes how efficiently the body will store macros in fat tissue. Both fat and carbohydrate are easily stored as fat reserve for later use and perhaps when high levels of both are ingested overall, that provides the best environment for fat storage and inhibition of fat use for fuel. On the other hand, protein is actually very inefficiently stored as fat and that’s why we now see that even in hypercaloric (eating over what you require) diets, those with a high proportion of protein don’t result in fat gain.1


The different macros also have differing thermic effects. In a nutshell, the thermic effect is the amount of energy we expend to process and store the fuel. Protein has the highest thermic effect of food at around 20 to 35% of the energy consumed, while both fat and carbohydrate are around 5-15%.2 Some other foods like chilli and medium chain triglycerides might also increase DIT dramatically.3


Protein also has the greatest effect of the macros on satiety4 (the feeling of satisfaction from eating) and eating a higher protein diet has been demonstrated to reduce overall food intake.5 This effect has also been observed in LCHF and ketogenic diets. I call this effect ‘autoregulation’ because the body better regulates the amount of food it desires, and therefore the amount of calories taken in, when protein intakes are higher, and possibly when there are higher protein AND higher fat AND sufficient vegetables.


One of the problems I’ve always had with if it fits your macros (IIFYM) eating is that it often doesn’t fit your micros! Many people end up eating a diet that is not of a high quality and although they are able to manipulate their macros eating anything they desire, it’s far harder to ensure that sufficient vitamins, minerals, secondary nutrients (antioxidants) and omega-3 fatty acids are also consumed. Typically, when people eat a higher proportion of natural, unprocessed foods, and more vegetables, they also tend to ‘autoregulate’ and not over-eat.

So, while overall energy is king, the way you achieve energy balance, especially over the long-term, is best achieved by a quality-macro approach to help you auto-regulate.

  1. Eat at least 80% natural unprocessed food
  2. Make sure you base your meals on 1-2 palm-sized portions of quality protein food
  3. Eat 6-9+ serves of veggies (and berries) per day!

That way, you’ll be best equipped to autoregulate the fuel you take in, to serve your goals without overdoing it.

Come and hear Cliff Harvey share his experience and expertise on all things nutrition in the free Expert Talks sessions at this weekend’s NZ Fitness & Health Expo. And see great healthy meal options being prepared and cooked live in the Nutrition Kitchen all weekend with ‘healthy chefs’ including Art Green, Carine Claudepierre, Wick Nixon and more.

Plus, there’s great workouts & classes available – including FREE Kids fitness sessions with Flow Academy! For more info & tickets visit