How many calories to eat per day – and lose Weight

Have you ever wondered how many calories you can eat in one day and lose weight?

Firstly let’s find out what is a calorie is.

So what is a Calorie?

So when I type in google the dictionary meaning of what a calorie is, this is what it says,

Calorie ˈkaləri,

  1. The energy needed to raise the temperature of 1 gram of water through 1 °C (now usually defined as 4.1868 joules).
  2. The energy needed to raise the temperature of 1 kilogram of water through 1 °C, equal to one thousand small calories and often used to measure the energy value of foods.

Thanks google, but you may still be scratching your head saying WHAT?

Calorie defined in simple terms

A calorie is simply a measure of energy in food.

When you look at the nutrition label on a packet and it states that it has 100 calories,

It’s simply describing how much energy your body can get from eating or drinking that particular item.

Calories are simply the body’s way of keeping track of the amount of energy it can consume.

A healthy balance occurs when we only put in as much energy as we can use and lose for the day.

Over time if we continue to eat more than our bodies can burn off, the left overs will be stored up as fat in your cells and you will begin to gain weight or mass.

But on the other hand, over time if you can burn or use up the amount of food/energy you eat in a day then you can either maintain or lose weight.

So in order to know how many calories you can eat in one day and lose weight?

We need to able to measure the amounts of energy/food we consume and use, in order to understand weight management better.

So how do we measure a calorie then?

In North America the term 1 Calorie is used generally on a food label which = 1 chemist’s kilo calorie = 1,000 chemist’s calories = 4.12 kilo joules

In Europe and other parts of the world they commonly use the term Kilojoule, that’s why both calories and Kilojoules are used.

One calorie the kind that is measured in food is the amount of energy your body will take to raise the temperature of one kilogram of water by 1 degree Celsius.

Or again how much energy your body can get from eating or drinking that particular item.

Different amounts of calories in food 

Every kind of food that we consume has its own calorie count or amount.

The amount of energy it stores as chemical bonds varies and is very different, for example

The average medium apple has about 70–90 calories

The average piece of bread (one slice, wheat or white): 66-80 calories

The average slice of pizza has about 200–290 calories

Rice (white, long grain, cooked, 1 cup): 200–220 calories

Chicken breast (boneless, skinless, roasted, 3 ounces): 100-120 calories

375ml can of Coke has around 161 calories

The average calorie content in beer can range from a lowly 64 calories to a whopping 198 calories per bottle.

Here’s how many calories are in 1 gram of the following:

· Protein = 4 calories

· Carbohydrate = 4 calories

· Fat = 9 calories

Calculating the amounts of Fat, protein, Carbs in your foods

How many times have you gone shopping and found your favorite food item, and thought I really want to know how to interrupt that food label.

You wanted to determine the amount of fat, protein, carbs in that particular packet of potato chips.

But you looked at it and thought I don’t even know where to start, it’s like you need a degree in food technology.

The good thing is thanks to technology, we have help at the touch of a button, as most every person carries a smart phone with them.

We now have access to many apps that do all the hard work for us by simply typing in the food you would like such as,

My Fitness Pal

Lose it

Fat Secret

Diet Diary

Again all these apps are simple to use either scan the bar code on the box of the item or type in the food and it lists all the important information you require.

Information such as the amount of calories in that amount of food, amount of protein, fat, carbs, sugar, fiber and so on.

Manually working out the amount of calories

I can anticipate some people saying hay what if I don’t have a smart phone or am not really tech savvy.

Can I still work out the amounts of calories, protein and fat, the old fashion way?

Well of course you can there are formulas that you can use to work out all the important nutritional information in your food.

So let’s say the next time you’re shopping and you find a packet of your favorite potato chips and you look at the label and it gives you the total serve amount.

The label states the following

Example: Potato chips  

Calories per serving 167

Servings size 7 Potato chips

Total fat 3 grams

Total saturated fat 1 gram

Cholesterol 0 mg

Sodium 250 mg

Total carbs 32 grams

Dietary fiber 4 grams

Sugars 11 grams

Protein 3 grams

As all the information you require is already available to you, below is how you can work it out the old-fashioned way,

Remember above I stated the amounts of calories there are in 1 gram of each of these below

· Protein = 4 calories

· Carbohydrate = 4 calories

· Fat = 9 calories

As the total amounts are given from the label, we work out the totals by the following formula,

Pro = 3 g, carbs = 32 g, fat =3 grams (all given on the food label above)

3 grams of protein in the potato chips, x 4 calories per gram of pro = 12 calories from protein

32 grams of carbs in the potato chips x 4 calories per gram of carbs = 128 calories from carbs

3 grams of fat in the potato chips x 9 calories per gram of fat = 27 calories from fat.

Total calories per serving:

12 calories from protein

128 calories from carbs

27 calories from fat

167 total calories per serving of Potato chips

(The final figure may be a few calories off from the actual food label due to rounding off.)

Work out these amounts in percentages

Percentage of calories from protein:

(3 g pro x 4 cal per gram pro) / 167cal x (100) = 7.18%

Percentage of calories from carbs:

(32 g carbs x 4 cal per gram carbs) / 167 cal x (100) = 76.65%

Percentage of calories from fat:

(3 g fat x 9 cal per gram fat) / 167 cal x (100) = 16.16%

100% (must equal about 100%)

How many Calories can I eat in a day?

Now that you know what a calorie is and that different foods contain their own amounts of calories. We also know how to work out the amounts of calories and fats and protein and carbs that are in your favorite foods,

The next thing you should determine is how many calories you can have or eat in one day. There are a lot of factors that determine the exact amount such as,

· Weight

· Gender

· Height

· Age

· Amount of activity you do in a day

· The way your body breaks down certain foods

· Amount of times you train or work out in a week.

· The list goes on and on

That’s why when you do a search for a calorie calculator it gives you the most average results for either male or female. There are many good calorie calculators that you can use to type in your age, height, age, gender, activity you do in a day, I also happen to have one available on the side bar that gives you a good indication of your daily calorie intake.

Based on that an average woman needs to eat about 2000 calories per day to maintain their weight. On the other hand they would need about 1500 calories to lose one pound of weight per week. An average man needs around 2500 calories a day to maintain their weight. You wanted to lose one pound of weight per week it would be around 2000 calories a day.


To sum it up all these figures mentioned above all depend on numerous factors, so based on this information it will be a great guide and place to start out and from here you can determine what measures you can put in place and change and alter this.

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  1. Thanks for your clearly defined post on how calorie counts measured. I’m always baffled especially when the clever marketeers promote their health counts per serving.
    I think the main way to reduce weight regards eating more healthier along with exercise to attain burning the calories away, failing that like you mention, the body store what’s not burned off as fat, hence most of our weight issues.
    Winter always creates a problem for us with regards to exercise due to the weather and early dark nights however once spring approaches we go for walks most nights for exercise as well as swim twice a week to maintain a more healthier lifestyle.
    Thanks for clarifying how to efficiently work out calorie counts,

    • Hi Simon,

      Thanks for leaving your comments, as simple as it may seem we complicated this simple rule of thumb which is don’t eat more than you can burn off in a day, so I am glad this has helped you and made sense, hope you enjoyed working out your daily calorie intake with the calculator to the side that was provided.
      Thanks again

  2. Great article
    I too want to eat healthy but also want to focus on my calorie counting goal which your article really helped me with and made things clearer.
    Thanks again

    • Thanks for the comments you left I am glad that this article has helped you and made things clearer for you as their is so much confusion out their I try to keep it simple and straight to the point.

  3. Great post, it really opens your eyes to how much you are actually consuming in terms of calories. Which makes me realise how much gym work I will need to do to burn it off again.
    I’m going to work out how many calories I can eat a day now. Thanks.

    • Hi Nick,
      Thanks for the comments you left, until you track your calories you will never know how much you can eat and burn off in a day.
      Hope the calorie counter on the side bar helped you out as well?

  4. Great post Charlie!

    The post title and headers were captivating. The content was informative, well written and structured so it was easy on the eyes and it flowed well.

    Congrats on a great website!

  5. Nice article. It’s not easy to loose weight but this article makes things a bit more clear, so maybe this is the time for me to loose those few pounds i always wanted to loose. Thanks for motivating me!

    • Hi Stratos,

      Thanks for your encouraging comments you left, I hope this has inspired you to finally make that important decision and lose that unwanted fat.
      If you need any assistance please let me know?

  6. Hi Charlie,
    I used to avoid reading the data about the amount of calories on the back of the packs because I couldn’t understand anything -like they were written in another language for me.
    Now that I know what they are about I will start to pay attention to them!


    • Hi Nathan,
      Thanks for your comments you left I am glad this has helped you understand reading food labels and it will cause you to pay attention to what you are not only buying but eating.

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