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Why (and when) you need to count calories

If there is one thing the Bodyscan team has learned from performing more than 17,000 scans (as at April 2022), it’s that perception does not often match reality. As an example, most men who come to us think they are taller than they really are!

We are all guilty of some embellished perception, whether it’s how well we drive, how much alcohol we drink or how much TV we watch.

This recent report from the Office of National Statistics confirms another split between perception and reality that we see at Bodyscan every day: many of us eat many more calories than we think we do and way more than we need. And that’s why we put on body fat.

At the same time, most people wildly overestimate the amount of activity they do and the number of calories they burn. Walking the dog and playing golf do not make you ‘very active’. Also, ‘rewarding’ yourself with a food ‘treat’ after exercise can create a mindset that positions overeating as something that can be mitigated by physical activity. To lose body fat, you need to be in a calorie deficit, so you cannot offset one against the other.

There are many writers, bloggers, influencers and Bodyscan customers who will say that losing weight is not about calories – that it’s about quality not quantity, or about timing. But whatever your diet – low-carb, low-fat, low-sugar, 5/2, 16/8, gluten-free, low-dairy, juice, Mediterranean – while you may not primarily set out to count or restrict energy intake, you will inevtiably consume fewer calories because they are being restricted by the now-absent foodstuffs or opportunities to eat in your diet.

Let’s be clear here: counting calories is not easy and, at its very worst, can contribute to an unhealthy psychological relationship between you and your food. So this post is definitely NOT a recommendation for everyone to measure what they eat.

But if you are overweight or gaining weight and want to reduce body fat, you certainly need to get a very good handle on (A) how many calories you eat now, (B) what your ‘maintenance’ level is (the amount of calories you need to maintain your current weight based on your energy expenditure) and (C) how many calories you need to eat to lose body fat.

NOTE: The number for (C) will typically be between 10% and 30% less than your maintenance level. So depending on how much you are overeating now (ie, how much above maintenance) you may have to reduce your calorie intake by anything up to 50% or even more. A DEXA body scan will help you calculate those numbers by accurately measuring your fat and fat-free mass.

With those numbers you can estimate your maintenance calories with our body composition calculator and measure them with popular fitness apps like MyFitnessPal. If that’s not your thing then serving your food on smaller plates can be one easy way of cutting back.

Even then it’s easy to get it wrong and underestimate or ignore drinks, protein supplements, snacks and alcohol.

The Bodyscan DEXA report excerpt below shows the variable progress of a heavily overweight (150kg) male who carefully counted calories during two phases of his diet-and-exercise programme, and just estimated them in another.

The results are striking:

When counting calories, and in two non-contiguous periods totalling five months, his DEXA scans show he lost more than 17kg of body fat (and just 1.8kg of muscle), shown by the orange arrows. But in the period that he stopped counting and just estimated calories he GAINED 3.2kg of fat and lost over a kilo of muscle.

The client was shocked by the fat gain because his exercise regimen had remained consistent and he believed his calorie estimations were too. In fact, when losing fat, he was in an approximate deficit of 900 calories a day. But the fat gain suggests he was in a calorie surplus of as much as 1300 calories a day! That is a swing of more than 2000 calories a day! So much for guesswork and portion control.

In the same vein a female client with very high muscle mass (from years of weight-lifting) but also increasing levels of fat was adamant that she was eating well below the estimated number of calories. But the maths simply doesn’t stack up – to be putting on muscle AND fat, short of a medical condition, she must be in a calorie surplus and therefore be underestimating her intake (and/or overestimating her activity level). As we say here, if you are not losing weight then you are not in a calorie deficit!

Many Bodyscan DEXA customers find it hard to believe how much fat they carry because they “eat healthily and cook everything from fresh” and “don’t eat processed foods.” Your food can be as fresh, organic and nutritious as you like, but if you eat too much of it, it will make you fat!