How many calories should we be eating?

Do you know how many calories your body needs to function? Probably not! Most people are eating either too many or too few of them. Both can be detrimental to you achieving your ultimate goal.




Nutritional science has helped us to understand what our bodies need, calorific wise, to live on a day to day basis. This is what is termed as the Basal  Metabolic Rate.

Your Basal Metabolic Rate (BMR) is the amount of  calories your body needs to function. From your heart beating, lungs breathing to maintaining a stable body temperature, it  accounts for 60% to 75% of the calories that you burn every day. So it stands to reason that you’d want to keep your BMR high if you want to have a leaner body (i.e. reduce the amount of fat that your body holds) and if we are honest from both a healthy and vain point of view that’s what the majority of us want!

How doe we do this? By exercising regularly and ideally  eating 5-6 times a day (3 meals and 2-3 snacks), you will keep your BMR high which in turn will burn more calories whilst you increase many positive factors in your health.

A well designed nutritional plan is a way to maximise energy, lose fat and gain lean muscle!

What do we need to take into account when planning our nutritional plan?

Below is a basic version of the calculations needed to discover your BMR. (A more accurate version is available but requires a more detailed table and further calculations on an individual basis).

Firstly our gender needs to be taken into account due to the fact that a woman’s body compared to that of a man’s body uses less calories per kg of body weight.

A generalisation is that a woman will burn 22 calories for every kg of body weight compared to that of a man who will burn 24 calories per kg of body weight.

A woman’s BMR = weight in kg x 22.

A man’s BMR = weight x 24.

The next step is to work out your  physical activity level. (PAL)

This is the ratio of your overall daily energy expenditure to your BMR, ( a guide to your lifestyle activity).

If you are inactive, mostly sitting throughout the day then this will be 1.2.

If you have;

A fairly active daily lifestyle which includes some walking and exercising twice a week then this will be 1.3.

A moderately active daily lifestyle  which would include exercising 2-3 times a week then this will be 1.4.

An active lifestyle exercising hard  more than 3 times per week then this will be 1.5.

A very active lifestyle which would be exercising hard every day then this would be 1.7.


Finally to discover your BMR you need to carry out the following equation;

Your BMR x your PAL

An example of this is a female who weighs 75kg and who has a moderately active lifestyle.

BMR= 75kg x 22= 1650 calories x 1.4(PAL) = 2310 calories.

Daily calorific intake to maintain her body weight would be approximately 2310 calories per day.

To reduce weight she would need to either decrease her daily calorie intake or increase her daily activity levels, or do both!

To increase weight she needs to increase her daily calorie intake and/or decrease her daily physical activities.

The above example is a rough guide to how we can begin to understand how to reach our goals. There is much more to take into account and we will consider those factors over the following weeks. The main thing that you have to remember is that once you begin to understand how your body works and what it requires and when it requires it, then you are well on your way to controlling your health and fitness and enjoying your life to a fuller extent!


Food groups can be  broken down into three basic areas;

  1. Carbohydrates.
  2. Proteins.
  3. Fats.

All of these groups are as important as each other.


This food group provides us with the energy to  enable us to do day to day activities. It is stored in the liver and muscles as glycogen which is a form of glucose/sugar.

Approximately 100g of glycogen (equivalent to 400 cals) may be stored in the liver and up to 400g (equivalent to 1600 cals) may be stored in our muscles, along with roughly three times its weight in water. These stores have to be replaced on a daily basis.  These figures are dependent on body size, weight and composition. If we increase our daily activities through exercise or physical work then we will need to consume more carbohydrate.

The purpose of the liver glycogen is to maintain steady blood glucose (sugar) levels whilst at rest or during prolonged exercise, which is extremely important to either control or to avoid diabetes altogether.

The purpose of muscle glycogen is to fuel physical activity.


Recent studies have revealed that the following guidelines can be used for daily intakes of carbohydrate;

Very light training: 3-5 g per kg body weight.

Moderate intensity, 1 hour daily: 5-7 g per kg body weight.

Moderate to high intensity, 1-3 hours daily:  7-12 g per kg body weight.

Very high intensity, up to 4 hours daily: 10-12 g per kg  body weight.


These guidelines are important for us when we start to consider what we need to fuel our body to reach our ultimate goals, whether it be to lose weight/gain weight or become a better athlete.