What is Energy?
When we talk about energy in relation to nutrition, we are referring to the fuel that our bodies need to function properly. Energy is required for all bodily processes, including physical activity, regulating body temperature, digestion, and even breathing. In this educational piece, we will explore what constitutes as energy and how it is related to the foods we consume.
How do we Measure Energy in Food?
The most common measurement of energy used in food is the calorie which is given the symbol 'Kcal'. You don't need to know the exact definition of it here, what's important is that you understand that we measure the amount of energy in food using the calorie. When we refer to energy in food it can be interchanged with the word 'calorie'.
The Role of Macronutrients in Providing Energy
To obtain energy, we eat food. This is because food is made up of macronutrients (Carbohydrates, Protein and Fat) and these, as well as having their own individual functions within the body, provide us with energy.
Each of the macronutrients provides us with a different amount of energy per gram eaten. And different foods contain different amounts of each macronutrient compared to one another. This is why the same weight of one food can provide you with a different amount of energy than another.
To achieve a healthy, balanced diet we must eat a wide range of foods from different food groups to meet both our Macronutrient and Micronutrient needs.
Now, lets take a look at each of the macronutrients below.
Carbohydrates: Energy Provided = 4kcal/gram
Carbohydrates are the body's preferred source of energy, especially when exercising. When consumed, carbohydrates are broken down into glucose, which is used as fuel for the cells.
Proteins: Energy Provided = 4kcal/gram
Proteins, in addition to their role in building and repairing tissues, can also provide energy. However, our bodies typically rely on proteins for energy only when our carbohydrate stores are extremely low like during starvation.
Fats: Energy Provided = 9kcal/gram
Fats are an excellent source of energy and provide the highest amount of energy per gram. They are broken down into fatty acids, which can be utilised as fuel by the body.
It's important to note that while all three macronutrients provide energy, they also have other critical roles in our bodies. This is why each macronutrient has its own 'Daily Requirement' so that our body processes are able to function effectively. Proteins, for example, are crucial for building and repairing tissues, while fats play a role in hormone production and insulation. Carbohydrates, aside from providing energy, also contribute to brain function.
Energy Intake and Expenditure
The balance between energy intake and expenditure plays a crucial role in maintaining a healthy body weight and overall well-being. When we consume more energy (calories) than we expend through daily activities and bodily functions, we gain weight. Conversely, if we consume less calories than we expend we lose weight.
The total number of calories we need daily varies widely depending on various factors, including age, sex, weight, height, activity level, and overall health. It is important to find the right balance and meet our unique energy needs to support proper bodily function.
Don't worry about this yet. We'll cover this in the near future.
Other Factors that Influence Energy Levels
While nutrition and caloric intake are vital for providing energy, there are other factors that can influence our energy levels. These factors include:
Hydration: Dehydration can impact energy levels and overall well-being. Staying adequately hydrated is crucial for maintaining optimal energy.
Nutrient Timing: Proper fuelling before exercise and replenishing nutrients post-exercise can impact energy levels and recovery.
Quality of Sleep: Poor sleep patterns or lack of restful sleep can negatively affect energy levels.
Stress Levels: High levels of stress can drain our energy reserves. Managing stress through relaxation techniques and self-care is important for maintaining energy levels.
In the next section we will explore how calculate your calorie requirements.