Energy Balance
What is Energy Balance?
Energy balance is a combination of the energy inputs and outputs into your body. Our primary energy input is the food we eat, usually measured in kilojoules (kJ) or calories (kcal).
Energy outputs are things we do that use up the energy that we have eaten. These include exercise, activity, heat produced by the body (thermogenesis) and the energy burned when resting required to carry out our body’s essential functions.
The UK’s recommended energy intake is 2,500 calories (kcal) per day for men and 2,000 calories (kcal) per day for women.
What happens when energy balance is not equal?
When energy balance is not equal – this can go one of two ways. The first is known as an energy deficit or negative energy balance – when more calories are burned than eaten. Typically, this can lead to weight loss, but it can also reduce your metabolism, concentration and physical performance, decrease bone mass and testosterone/thyroid hormones and increase fatigue.
The other end of this would be an energy surplus or a positive energy balance – when more calories are eaten than burned. Sustaining this may lead to weight gain, but it may also put you at risk of metabolic diseases, including type 2 diabetes, high blood pressure, heart disease, stroke and some types of cancer.
It is important to remember these changes occur when this behaviour is repeated for a more extended amount of time. Eating a big meal or indulging during your holiday is not likely to cause long-term weight gain. Missing a few meals is not going to make your body mass drop dramatically, either. Whilst it is not always possible, maintaining a neutral energy balance in the long term is ideal to allow your body to perform optimally.
What is BMR?
BMR stands for Basal Metabolic Rate. Put simply; it is a number referring to the energy, usually in calories (kcal), which your body requires to carry out its most important and basic (basal) processes needed to keep you alive. This includes things like respiration, circulation, and making new cells.
You can calculate your own approximate BMR here. Still, please remember that the actual number is challenging to measure (it is usually calculated in specialist labs) and may vary between individuals even of the same weight, height, age and gender due to our unique genetic differences.
What is RMR?
Resting metabolic rate, or RMR, indicates the number of calories your body typically burns at rest. RMR is often measured in the morning before breakfast after a good night of sleep.
These definitions are pretty similar, but you can think of the RMR as an “general estimation” of BMR for the individual.
Is calorie counting the best way to maintain energy balance?
Although it seems simple, this is unlikely. Calorie estimates are not always spot on and can be based on average calculations taken many years ago. Many factors also create considerable variations in the nutrition of foods that can be difficult and costly to measure. These include:
• Soil quality
• Climate
• Visual differences
• Farming methods
• Packaging
• Processing
• Preparation
• The way we eat the food
Over the last few decades, many changes have occurred that collectively may contribute to a net weight gain in a large amount of the population. An increased sedentary lifestyle and environment and access to fast and potentially calorie-dense foods can play a part. Body awareness signals and being mindful of our hunger and fullness cues also play important yet often forgotten role.
It is also essential to focus on nutrients and not just the numbers. For example, nuts and seeds may be reasonably high in calories, which puts many people off eating them, but nuts are a great source of protein, mono and polyunsaturated fats such as omega-3s, and minerals like magnesium selenium and zinc. Eating a varied and balanced diet combined with doing regular and enjoyable movement and exercise is a great step to promoting a healthy energy balance for yourself.
References
Nhs . 2018. Cut down on your calories. 13 August. Eat well. [Online]. [16 April 2021]. Available from: https://www.nhs.uk/live-well/eat-well/cut-down-on-your-calories/#:~:text=An%20important%20part%20of%20a,a%20day%20(8%2C400kJ).
Mattes RD, et al. Impact of peanuts and tree nuts on body weight and healthy weight loss in adults. J Nutr 2008;138:1741S-1745S.
Andrews, R. . All About Energy Balance. Precision Nutrition. [Online]. [16 April 2021]. Available from: https://www.precisionnutrition.com/all-about-energy-balance