What is meant by calorie in, calorie out?

« Back to Articles

I have been considered overweight for most my life and was most the time, not happy with my weight.

Everything I tried just wasn’t working and it didn’t take me too long to be convinced that the market was filled with fads. I know that the best way to lose weight is by eating a healthy diet and being sufficiently active, rather than deciding that if one fad doesn’t work I should try another one. A healthy diet and being active is basically following the concept of the "Calories in, Calories out" approach, which the most popular and successful weight loss programs are all based on. So the question is what is "Calories in, calories out" exactly?

Calorie Deficit for Weight Loss

The "Calories in" are the foods that we consume and "Calories out" is the energy we use to function, exercise and carry out other tasks. The formula is based on the concept that to burn fat and lose weight you must eat fewer calories than your body uses i.e. Calories out is greater than Calories in. This is called a calorie deficit.

Calorie in vs. Calorie out

I enjoyed my food and did not want to change anything there so I stepped up my exercise instead. In fact, when I started exercising I became hungrier and ate even more than before. I figured given the amount of exercise I was doing, this would balance things out.

Oh how wrong I was.

What I know now but didn’t know then was that my exercise was nowhere NEAR close to making up for the amount of calories I was eating, which would explain the difficulties I was having losing weight at this point in time.

What is Calorie Counting?

The "Calorie in, Calorie out" approach is the best way to lose weight properly and to be truly successful at it, you have to count calories.

Did Not Want to Calorie Count

Initially, this was something I clearly did not want to do. Who wants be a calorie counter, the thought of it is so tedious, annoying and difficult. The logic convinced me to surrender to the idea and I started to look at the calories in the food that I ate and how much I would burn through exercise. If I know how many calories I have to limit myself to each day to lose weight, than I simply have to count the calories in my food and ensure I stay within the daily limit.

How to count calories quickly and easily

The labels of food in the supermarket was helpful, the calorie content was right there, otherwise I would quickly lookup the calorie content of the food I ate online. There are many sites that can do this and you can search for calories in food via your favourite search engine. It was fairly quick and easy and the best thing is I very quickly learned to look at food ingredients and meals and estimate confidently the calorie content.

Calories may be labeled as calories, cal, kilocalories, kcal

Calories may also be expressed as Kilojoules or kj. If this is the case you will need to convert to calories by dividing by 4.184.

1 calorie = 4.184 kilojoules

It was shocking how many calories some foods contained, particularly the junk food. I knew certain things would be higher calorie but not THAT much. And don’t get me wrong, everyone should exercise, it not only burns calories but has a host of other benefits for our bodies, BUT, the calories I would burn from intense exercise would maybe make up for a small chocolate bar or the like.


I have made it very clear that when it comes to weight loss that focusing on the diet will have a much more profound effect on your calories then exercise. But I also want to put great emphasis on exercise and the benefits I have experienced from it.

So as you may know I thought that exercise was the answer to ALL my weight related problems. Truth is, diet was the main factor, but exercise still does its job in the "Calories in, calories out" formula. I could still burn a few hundred calories from a half hour of exercise. This could very well be and often was the difference between a calorie deficit and putting on weight.

Calorie Awareness

Sounds silly when I say it out loud but "Calories in, Calories out" helped me to understand just how much a role diet played on weight loss and maintenance.

Counting calories was not difficult at all and the general consensus is that anyone will quickly learn the ability to estimate the calorie content of the foods they are faced with. It is a very important skill for weight loss, crucial to calculating and creating a calorie deficit. It is empowering to know exactly what impact certain foods will have on your weight loss and to be able to make more informed decisions about what you put in your body.

So start counting and be shocked by the calorie content found in your food and delight in how your new knowledge will help you lose weight.