Does Counting Calories Work?

Is managing your weight as simple as subtracting calories out from calories in? Or are the equations for fat loss and muscle-building a bit more complicated?

Dig more than skin deep and the human body is a very confusing thing. At any given moment, an uncountable number of interlinked biophysical processes are happening inside you, from electrical signals flashing along nerves to chemicals shuttling between cells, which control everything from the movement of your muscles to whether you can remember where you left your house keys. It's a complex system and it needs a lot of fuel to run.

To power the human body (and this is a gross oversimplification of how it actually works) we need to eat. If we eat too much, we end up with a bunch of leftover energy, which gets stored for later as fat. If we don't eat enough, then the system doesn't have enough energy to function properly and taps those stores to make sure it keeps ticking over.

Which brings us onto calorie counting. It’s a way to monitor how much energy goes in so you can balance it against how much gets burned up, the idea being that with a bit of basic math you can keep to either a deficit (in which case you'll lose weight) or a surplus (which means you'll put weight on).

Although this concept has been around for years, it’s still easy to be sceptical – does counting calories actually make fat loss or weight gain easier? The following article will explore why calories are important, explain how you can count calories safely, and most importantly, take a critical look at whether calorie counting actually works long-term.

What is a calorie?

Strap in, because things are about to get technical.

A calorie is a unit of energy. Specifically, the amount of energy needed to raise the temperature of 1g of water by 1°C. In that context, it's very rarely used by scientists these days, having been replaced by the joule.

In food, of course, it's very commonly used. But technically, we're not talking calories – we're talking kilocalories (kcal).

1kcal = 1000 calories.

A kilocalorie can also be written as Calorie, capitalising the 'C'. We know – it can be super confusing

1000 calorie (cal) = 1 Calorie/kilocalorie (kcal)

Our bodies need energy to do what they do, that’s why calories are so important. However, keeping track of calorie intake is not always easy. If you want more on the science behind calories, check out our article How to Calculate the Energy Value of Food, written by one of our expert nutritionists, Rebecca Williams SENr, RNutr.

The history of calorie counting

Over 100 years ago, a guy called Wilbur Olin Atwater developed a way to measure the calorie content of foods. It’s called the Atwater system (who’d have thought?) and it’s still used today. Full disclosure: it’s not 100% accurate. But it’s still pretty good.

According to the Atwater system:

1g of fat = 9kcal

1g of alcohol = 7kcal

1g of carbohydrate = 4kcal

1g of protein = 4kcal

So 100g of butter (which is mostly fat) will contain more calories than 100g of oats (which is mostly carbohydrate). Fibre is not accounted for in this system, but because it’s not digested as well as other carbohydrates, it’s usually assumed 1g of fibre = 2kcal.

Although the Atwater system helps us understand calorie counting mathematically, it's not the most practical if you actually want to know how much energy there is in what you're eating.

Why count calories?

Just as you can figure out how many calories are going into your body, you can also calculate how many you 'burn'. Again, we're actually talking kilocalories here. And unlike food, where you can use scales and nutrient types to get to a decent estimate, figuring out energy burn is trickier.

If you were just to lie in bed all day and not move, you'd still burn a lot of calories just keeping yourself breathing, blood pumping, nerves firing, cells growing, and everything else your body does to keep you alive. This is known as your basal metabolic rate (BMR) – the amount of energy required for you to do nothing at all. In most people, BMR accounts for up to 75 per cent of your total calorie burn. The rest is based on how much you move around.

The more you move, the more calories you need to fire your muscles. But also, the more muscle you have, the more calories you burn doing nothing. That's because muscle is 'active', whereas fat just sits there and requires no energy to maintain. Then again, the bigger you are, the more energy you need to move around. That means you need to eat more, which also means you burn more energy digesting the food you eat...and so on. Like we said, it's complicated.

Helpfully, there are tonnes of apps and calculators out there now which can help you to estimate your calorie needs. This is one of our favourites. If you want a more accurate read, then fitness trackers monitor things like heart rate, blood oxygen levels and how much distance you're covering to give a more personal picture of your daily calorie burn. Bear in mind, though, that they're still estimates.

This is why the entire concept of calorie counting exists, because calorie intake is person-specific. Calorie ‘needs’ vary from person to person. ‘Needs’ is defined roughly as the number of calories someone needs to maintain their weight. If someone is eating fewer calories than they need, they’re in what’s called a calorie deficit and will lose weight. If someone is eating more calories than they need, they’re in a calorie surplus and will gain weight.

So why count calories? Well, it is likely a person is counting calories because they’re trying to eliminate weight gain, as excess calories are normally stored in the body as fat. Alternatively, someone very active like an athlete might want to count calories to track progress of muscle growth, as excess calories can be converted by the body into muscle with exercise.

Calorie needs vary based on height, weight, age, gender and a whole host of other factors. Here are a few examples:

  • The bigger the body, the more calories it needs.
  • The higher your level of physical activity the higher your calorie needs because you need more energy to do all that running, hopping and jumping.
  • Muscle burns more calories than fat, so if you have a higher muscle percentage compared to someone of the same height and weight, your calorie needs will be higher.

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How to count calories

It’s possible to 'count' the calories of any food, but the approach you take is entirely up to you. You can do it:

The easy way – check out the back of any food packaging as it’s legally required to display calories

The hard way – calculate the calories using the Atwater factors

The really hard way – through buying loads of expensive and fancy science equipment!

Bit of a no-brainer, eh?

Huel makes the process of calorie counting a lot easier too. For example, one scoop of Huel = 200 calories and two scoops = a 400-calorie Huel meal, giving you ease and control over your calorie intake. There’s many more reasons why Huel is great for calorie counting, but we’ll get to that later.

Our top tips:

  • The easiest way to calculate meals and days where multiple different foods have been eaten is to use an app like MyFitnessPal. All you have to do is input the foods you eat and it will calculate how many calories you’ve eaten for each meal/day.
  •  Be careful that you’re getting the correct serving sizes. Processed foods often have teeny-tiny serving sizes to make them look healthier than they actually are (we don't know anyone who's happy eating 1/6 of a pizza, despite what the packaging says).
  • Once you’ve got to grips with calorie counting and have a good idea of the foods you eat, you could stop counting which can give you more freedom and flexibility.

The good news...

So if you know how many calories are in the foods you’re eating, and you know your calorie needs, it’s easy to use that information to help you lose fat or gain weight.

The not so good news...

But calorie counting and measuring your calorie needs will never be totally accurate. It’s better to think of them as a best guess so it’s probably a good idea to track your progress in more objective ways too. So, a set of scales could help here, as could taking photos to get a better idea of your body shape, using a tape measure, or just tracking your exercise performance (eg whether you're running quicker or lifting more weight)

If you think you’re eating the calories you need to lose weight but the scales haven’t moved, then something isn’t quite right. That’s not the end of the world – simply lower your daily calorie intake by another 200kcal and then weigh yourself over the next two weeks. It’s likely that you’ll start to see some progress.

It’s also important to note that changes, from your body weight to your physical activity, will affect your calorie needs. Therefore you will need to redo your calorie needs calculations to see if you need to change the amount of calories you are consuming.

Should I count calories?

Counting calories isn’t necessarily a bad idea, but they’re just one piece of the puzzle. As a society, we fixate on them but they don’t give you everything you need to know – they tell you how much you’re eating but not what you’re eating. It’s worth remembering there’s a significant difference between calories and food quality.

You could eat 1000kcal of donuts and lose weight or 1000kcal of salmon, rice and broccoli and also lose weight. But it will be much harder to lose weight eating donuts because they’re not as filling as salmon, rice and broccoli. The latter is also a healthier meal and is likely to leave you feeling better and able to do more things, but you wouldn’t know that just by looking at the calories.

Calories don’t tell you how much of each nutrient a food contains either. How are you going to know the amount of protein or vitamin C or iron from the calorie value? You can’t.

When calorie counting can be helpful When calorie counting can be unhelpful
If you’re having a hard time understanding why you’re not losing/gaining weight If you are already a healthy weight
If you're tracking specific goals eg for weight training to increase the amount of weight you can lift If you want to eat healthily (tracking food quality)
If you have an eating disorder eg anorexia
If it takes time and enjoyment out of eating and preparing meals

How Huel can help

Man adding Huel to a shaker

Now that we’ve looked at the pros and cons of calorie counting, it’s fair to say recommending a ‘one-size-fits-all’ approach doesn’t work, because each case is person-specific. If you are still unsure, you could use calorie counting to help you understand more about what you eat, and ditch it once you feel you’ve learnt enough. Alternatively, if you have decided that calorie counting is right for you, Huel can make the process a lot easier.

  • Know exactly how many calories you’re consuming: As mentioned earlier, we’ve conveniently made each scoop of Huel Powder and Huel Hot & Savory exactly 200kcal. This makes tracking your daily calorie intake super easy. We recommend two scoops per portion (400kcal meal) – but this can be tailored to your individual requirements.
  • Calorie counting AND food quality combined: The good news is Huel is one nutritionally complete food, so we’ve spared you the pain of counting up individual ingredients and scanning barcodes into fitness apps! You’re welcome. As well as tracking calories, you can easily work out the exact nutritional value of your meal – check out our Huel Formula Explained page for more.
  • Huel is easy to measure: On all first orders of Huel V3.0 Powder, Black Edition & Hot & Savory, we include a FREE Shaker/Pot and Scoop. We want to make the measuring process as easy as possible for you, so there’s no need to go out and buy yourself any fancy measuring equipment.
  • Portion control: Huel acts as an amazing guide to portioning meals properly, helping you achieve a calorie deficit. It’s easier to fall down that slippery slope of overeating when your portions are too big or you can go back for seconds or even thirds!
  • Consistency: As Huel makes calorie counting easy, it’s simpler to achieve consistency in your eating routine and regulate your daily calorie intake.

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Calorie counting works if done correctly, and it can be really beneficial under the right circumstances. But ultimately, there might be a fair amount of trial and error first to figure out what’s best for you. Remember that calorie counting focuses on how much, but don’t forget about what you’re eating too.

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