Macronutrients & Energy
Estimated reading time: 5 minutes
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Lesson 5: Macronutrients & Energy
What are macronutrients?
Macronutrients are the 3 main suppliers of nutrients that your body needs in large quantities for energy as well as vital function. They are carbohydrates, proteins, and fats.
The different macros yield different amounts of energy:
1 gram of carbohydrate contains 4kcal
1 gram of protein contains 4kcal
1 gram of fat contains 9kcal
In addition to providing the body with energy, macronutrients also serve a lot of other vital functions such as hormone production and immune system health.
The two most common units for measuring energy from food is the kilojoule (kJ) and the kilocalorie (kcal). New Zealand and most countries in the world predominantly use kiloJoules as a measure of energy and the U.S and UK predominantly use kiloCalories. One calorie is equal to 4.18 joules.
Energy balance
Energy balance is the relationship between energy that you are taking in (food and drink), and energy that you are using up (metabolism & exercise). This balance determines your bodyweight and also impacts your overall health.
Your body can use energy up in a few ways:
Basal metabolism: A lot of energy is required just to keep your body alive and to maintain vital function. About 70% of all the energy you are taking in goes towards that maintenance.
Digesting and processing food: This is called the ‘thermic effect of food’, where the work required for your body to break down food and absorb it, actually uses up some energy in the process.
Exercise: Energy is expended through exercise that you can categorise into two forms; exercise that is planned (exercise activity) or exercise that is unplanned (non-exercise activity thermogenesis or NEAT for short). NEAT types of exercise can include how active you are at work or even walking to and from work.
The amount of energy used during exercise activity can vary depending on how active you are but is usually around 10-20% of your daily expenditure. Energy expended through NEAT will also vary between individuals and differing professions. This generally contributes the least to your energy expenditure.
What happens when your energy is not balanced
When your energy expenditure and your energy intake is not balanced, your weight will change.
If you are taking in more energy than you are expending, you will gain weight
If you are expending more energy than you are taking in, you will lose weight.
It can be confusing when you don’t know exactly how much energy is coming in or going out, but remember it isn’t just exercise that uses up energy. Your basal metabolism accounts for 70% of your output and if your body is under fuelled, then it will actually slow down its processes to match the intake over time.
This is why you can often see results early on in a weight loss journey, but plateau after a while as your body has adapted to the new ‘normal’ energy balance. It’s important to prevent that from happening because you could find yourself eating less food and exercising more, but still not lose any weight.
‘Yo-yo’ dieting
This is where someone can continuously lose and put on the same weight every year by cycling on and off different diets or even the same diet. A typical weight loss diet prescribes a drastically reduced energy intake which means a rapid decline in weight, at first.
Metabolism then slows down as it is adapting to fewer calories. The weight loss stops and there is a tendency to go back to normal eating habits. With the new (slower) metabolism and the same old eating habits, the weight packs itself back on. Rinse and repeat.
How you can avoid this
To avoid these unfavourable changes in metabolism, weight loss (or gain) should be a slow and sustainable process. This process should allow for the development of new lifestyle habits, including your relationship with food and exercise.
Your relationship with food begins with your perception and beliefs of what you can and cannot eat. It also involves how you respond when you eat in a way that aligns or doesn’t align with those beliefs.
Food as a continuum
Thinking of food as a continuum rather than a black and white ‘good vs bad’ perspective helps you develop a healthier and more sustainable relationship with food. Try to think of food as what you should eat less, eat some, and eat more of.
What the continuum looks like for general wellness
Foods that we should eat less of:
Fried foods
Heavily processed foods (like deli meats)
Sugary drinks
Sweets and baking
Foods with more than 10 grams of sugar added
Trans fats
Foods we should only eat some of the time:
Protein powders
White breads, bagels, wraps, pastas
Most dairy products
Soft cheese
Minimally processed lean meats
‘Healthy’ snack bars
Dried or minimally processed fruits
Foods we should eat more of (and most of the time):
Lean meats
Unprocessed foods
Beans and lentils
Fresh and frozen fruit
Vegetables
Seeds and nuts
Eggs
Plain Greek yoghurt
For someone training more frequently or to a higher intensity, the ratio should be higher in the ‘eat more’ and less in the ‘eat less’ zones.
Budgeting
You can apply the ratios above to your food budget as well. Spend 2/5 of your weeks food budget on foods you should eat more, 2/5 on foods you should eat some, and 1/5 on foods you should eat less.
If you spend the time needed to work out your food budget and make the time needed to allocate it, you will find that fitting healthy options into your budget is not as expensive as you might think.
Tips:
Only buy produce thats on sale at the supermarket
Look up produce that you aren’t familiar with to expand your repertoire
Visit your local farmers market where fruit and vegetables are consistently more affordable
Make time to plan