So what is a calorie?
It is a measure of how much potential energy that food contains. Looking at our macronutrients, a gram of carbohydrate has 4 calories a gram of protein has 4 calories, and a gram of fat has 9 calories. However, the breakdown of these nutrients varies, for example, protein requires more energy to break down in comparison to carbohydrates, and therefore the number of actual calories you take in differ!
The nutritional label on a pack honey porridge says it has 160 calories, and looking further down the label it shows the porridge has 2 grams of fat, 4 grams of protein, and 32 grams of carbohydrates, producing a total of 162 calories. Of these 162 calories, 18 come from fat (9 cal x 2 g), 16 come from protein (4 cal x 4 g) and 128 come from carbohydrates (4 cal x 32 g).
Our bodies burn the calories through metabolic processes in which enzymes break the carbohydrates into glucose and other sugars, fats into glycerol, and fatty acids and proteins into amino acids. These molecules are transported through the bloodstream to the cells, where they are either absorbed for immediate use or sent on to the final stage of metabolism where they are stored as energy.
The amount of calories our cells need to function depends on the individual; height, weight, gender, age, and activity level all affect your caloric needs. There are three main factors involved in calculating how many calories your body needs per day:
- Basal metabolic rate
- Physical activity
- Thermic effect of food
Your basal metabolic rate (BMR), also known as the resting metabolic rate, is the amount of energy your body needs to function at rest. This accounts for about 60% of calories burned in a day and includes the energy required to perform basic functions, like breathing, keeping the heart beating, kidneys functioning, and stabilising body temperature. Many factors determine your BMR, however, men, in general, have a higher BMR than women.
Physical activity contributes to your daily calorie needs; those with a more active lifestyle have a higher energy demand and will need to increase their calorie intake. Light to moderate activity (roughly 30 mins) will expend around 100 calories.
Energy balance is essential in maintaining a healthy weight. Fluctuations in weight can occur when there is a difference between the number of calories you expend against the number of calories you consume. For example, eating 2000 calories could result in you gaining weight if you do not expend those 2000 calories through physical activity.
You can calculate your BMR using the Harris-Benedict formula below:
- Adult male: 66 + (6.3 x bodyweight in lbs.) + (12.9 x height in inches) – (6.8 x age in years)
- Adult female: 655 + (4.3 x weight in lbs.) + (4.7 x height in inches) – (4.7 x age in years)
The food you eat influences your energy requirements. During digestion, your BMR raises between 67-10%, this is necessary not just for digestion, but also absorbing, metabolising, and storing food throughout the body.
If you are on a particular diet, for example, a 1,200 calorie diet, dividing that into either four or six meals of 200-300 calories will keep your metabolism high and reduce the chance of gaining weight.
Hormones in our body influence the food we eat and the fat we burn. Ghrelin helps regulate appetite, cortisol which is a stress hormone that can increase abdominal obesity, androgen hormones that help build muscle, burn fat, and increase insulin sensitivity and impair gut health.
So eating more calories may result in weight gain if the energy is not expended. The biochemical aspects of an individual can affect calorie intake; hormones determine what happens in our bodies and what we are suited to, for example, some people stay healthy on a paleo diet (high protein), whereas others on a keto (high fats). Low-calorie diets mean more fat! Starving the body of essential calories for a long period of time means the body slows itself down, this includes metabolism and body temperature. An individual can become unable to burn fat, and when they increase their calorie intake they are very effective at storing fat. A healthy weight should be determined by the types of food that you eat as well as lifestyle changes like exercise and not calorie intake.
At Perfect Balance Clinic, one of our qualified Nutritionists can help you take control of your weight by making adjustments to your nutrition, lifestyle, and exercise routine to help you reduce body fat, and get you feeling fit and healthy!
If this resonates with you then…
Take advantage of our 15-minute sessions either with a Nutritionist or Functional Medicine Practitioner, designed to give you the support you need with your concerns and to get you started on your road to recovery. Find very quick and effective results!
This article was written by our team of specialist therapists at Perfect Balance Clinic. If you would like more specific advice about how our team can help you with this condition or symptoms you may be having, please complete the contact form below and one of the team will get back to you shortly.