Energy Balance

You might often hear people talking about their ‘macros’ and tracking the food that they eat and wonder what on earth for? Why would you go to all that effort of counting every single thing that you consume? Firstly, the word ‘macros’ refers to macronutrients which are the major food sources in which you consume. Them being, carbohydrates, protein and fats. You’re probably sitting there thinking to yourself, that it’s all those gym junkies and fitness gurus in which this is explicitly applied to. On the contrary, the notion of Energy Balance is applicable to all, whether you are looking to shift some excess weight or you simply just want to feel like you have more energy to get through the day.

The notion of energy balance is quite a simple one: the amount of calories (or kilojoules, kj) you introduce from exogenous sources (your diet) minus, the amount of energy output (the energy you burn throughout the day). With this relationship, you can end up in one of three positions:
1. Energy equilibrium, where the amount you consume is equal to the amount you burn.
2. Positive energy balance, where you consume more calories that you burn.
3. Negative energy balance, where your energy output is greater than what you consume.

Despite this grossly simplistic model, it is much more complicated than that since the energy output is largely based on the foods that you eat, your physical activity level (PAL), as well as the type of person you are (age, sex, genetic make up). It is also well documented that the brain-gut connection is extraordinary complex. As a result of this, being in a particular energy balance state is honestly harder than it looks on paper. Factors such as mental status, exposure to certain environments and physical well-being can all play a part in influencing in what you are going to consume and ultimately, your energy balance.

What are the dietary factors that I need to consider when analysing my energy balance?
Your energy input is comprised of carbohydrates, protein, fats and alcohol. A gram of carbohydrate and protein contains 17 kj (4 calories), whereas fat contains 37 kj per gram (9 calories) and alcohol 29 kj (7 calories). While I can appreciate that you don’t eat the same food at the same time everyday, simply becoming more aware of what you are introducing into your body can be that much needed first step to living a more healthy and energized life!

From anecdotal sources as well as personal experience, the metabolism of alcohol is what prevents many people from achieving their weight loss goals. Alcohol cannot be stored in the body as potential energy and is rather given priority over all other macronutrients since it is a ‘toxin’ that we voluntarily introduce. The Australian Guidelines advise that no more than 2 standard drinks should be consumed on any day to reduce the risk of alcohol related disease or injury. Note that a standard drink in Australia is 10 grams of alcohol and this is based on assuming that the liver metabolises alcohol at an approximate rate of 10 grams per hour (although this value varies between individuals and is influenced by sex, age and body mass). In addition to this, the guidelines recommend drinking no more than four standard drinks in a single occasion to further reduce risk. I can certainly appreciate that these are merely guidelines, and a lot of people do not adhere to them. However, the guidelines are set for a reason; to ensure the health of all citizens and reduce the risk of long term disease which is extremely prevalent in today’s society.

What about energy output?
Briefly touched on before, your energy output is comprised of factors such as physical activity level (PAL), your basal metabolic rate (BMR), the thermic effect of food (TEF) and thermogenesis. For simplicity, this article will ignore thermogenesis as it can be considered a minor contributor to energy expenditure in most circumstances.

The PAL determines a large portion of the energy that we expend on a day-to-day basis. Due to the nature of some jobs such as those revolving around an office, the PAL of those workers are not very high due to the amount of sedentary behaviour. Although this can be combated by utilising a standing desk since standing rather than sitting increases energy expenditure. The Australian Department of Health has physical activity guidelines that equip citizens to combat themselves against long term disease. These include to accumulate 150 to 300 minutes of moderate intensity physical activity, or 75 to 150 minutes of vigorous intensity physical activity, or an equivalent combination. It is further recommended to engage in muscle strengthening activities on at least 2 days each week (these guidelines are for adults aged 18-64 years). Now, these figures may seem like an overwhelmingly excessive amount to a lot of people. You may be thinking: how on earth am I going to find the time to dedicate to this new amount of weekly exercise? Note, that activities such as cleaning the house, mowing the lawn, certain roles undertaken at work and walking for transport (among others), all constitute as physical activity.

Your basal metabolic rate (BMR) refers to the minimum amount of energy that your body expends at rest in order to keep you alive. You can think of it as the ‘baseline’ of energy expenditure that your body will expend daily before any activity is undertaken. As briefly mentioned before, there are a number of factors that can influence (increase or decrease) an individual’s BMR. It is not a static value and fluctuates according to the physical state of a human being. Some factors that can increase basal metabolism include proportion of lean body mass, body temperature, caffeine intake, exercise and activity of the nervous system as some examples. Of these factors, research has indicated that the amount of lean body mass constitutes the greatest increase in BMR in a person.
Note that it has been postulated that a ‘tolerance’ of caffeine can occur in an individual overtime, thus caffeines’ overall influence on metabolic rate can be reduced. Evidence for this has not been explicitly examined in this article, however I may investigate this further in the future since it is estimated that 3 in 4 Australians consume coffee on a daily basis; clearly a topic well worth discussing.
As there are factors that increase BMR, there are also factors that can decrease it. Them being, restriction of caloric intake, lower amount of body mass and those individuals who are over 30 years.
It is likely that you have come across BMR at some point and also come across the various calculators which assist in predicting one’s BMR. If you have not, that’s not to worry as we will be briefly discussing them here. While it is arguable that these calculators are merely subjective, I believe they do have their place. They are an excellent predictor and it gives you a sense of direction when you start to manipulate the amount or type of foods that you eat to compliment your daily energy expenditure and overall well-being. One particular equation that is used in predicting the BMR is the Schofield Equation (1985). For males the BMR= 0.063*(BW)+2.896 (where BW is body weight in kg). Similarly, the equation for females is BMR=0.062*(BW)+2.036. The resulting answer you get is expressed in mega joules (MJ) so you need to multiply your BMR by factor of 1000 to get an expression in kj. The BMR also needs to be multiplied by a physical activity factor (PAF), in order to get an estimated energy requirement (EER) which is a daily target for food consumption. For example, a very active individual would multiply their answer by 1.8-2.0. This would equate to the amount of food they would need to consume daily in order to be at an equilibrium with respect to their energy balance. I’ll provide you with a sample calculation below for a typical male who weights 75kg and has a PAF of 1.9; this is a very active individual.
BMR= [0.063(75)+2.896]*1000
BMR= 7621 kj (dividing by 4.18 equates to 1594 calories).
EER= BMR*PAF
EER= 7621 * 1.9
EER=14480 kj (Dividing by 4.18 gives us 3464 calories).
Note that there are many other calculators out there to estimate your BMR and EER respectively, however this is the most familiar to me at the moment.

Lastly we need to discuss the thermic effect of food (TEF). The TEF is essentially the energy your body expends on metabolism of food (digesting, absorbing and storing nutrients). According to Byrd–Bredbenner, Berning, Kelley & Moe, (2019), the TEF accounts for 5-10% of the energy expended per day. So if the EER is 3000 calories, the TEF equates between 150 to 300 calories. This is relatively consistent with various studies, and most literature claims that a higher protein intake results in a greater thermic response and promotes satiety compared to other macronutrients (Rolland, Westerterp & Wilson, 1999) (Westerterp, 2004) (Byrd-Bredbenner, et al., 2019).

What should I eat?
While I am not a dietitian or even a nutritionist for that matter, these statements are simply based off what I’m learning. Firstly, it is important however to acknowledge that there are certain foods which in essence contain ’empty calories.’ Typical foods include beer, soft drinks, cakes and biscuits for example. These foods can also be referred to as energy dense foods, as they weigh very little, however have an extraordinary amount of energy packed in them! These are the type of foods that we should consume in moderation and rather choose nutrient rich foods for our general day to day meals.
While you may feel as if you are in a caloric deficit, consuming foods that are nutrient poor or energy dense can still ultimately make you feel flat or low on energy or just simply tired all the time. However, just be mindful that a sudden drastic change in your diet is the last thing you want to do to your body. Like anything, a gradual shift is much more likely to be sustainable in the long run.

Lastly, I will pose the idea that there is a time for all three energy balance positions to be present in your life. For example, putting on lean muscle mass is complimented with a positive energy balance. While you may have some inevitable fat synthesis, synthesis of lean body mass would be optimised (this can be debatable though, however, it will not be discussed in detail here. The right training would be needed for synthesis of lean body mass to occur as well). On the other hand, in an attempt to shift some of that stubborn fat, a negative energy balance and good old fashioned patience is crucial. I have planned to go into more detail into each of the three energy balance positions in the future, but hopefully these ideas are enough to stimulate some of your own thinking.

Life is a journey and incremental steps will ultimately get you a great distance. Start experimenting with the foods that make you feel good and the ones that don’t. Once you get to know your body, manipulating your energy balance status can become fun and quite an easy thing to do. But as it was mentioned before, being aware is the first step in taking that step to living a more wholesome and fulfilling life.

Anthony