Macro and Micronutrients - What Are They?
BY CHLOE FRENCH, ANUTR
Most people have heard of or even tried counting calories or macros, but what actually are they and is this a good approach when trying to improve your diet?
A calorie is the amount of energy needed to raise the temperature of one gram of water by one degree Celsius (1). This method is used to identify the amount of energy in different foods, and thus their kcal value, which can be found on the package labelling.
Energy is essential for all bodily functions including breathing, walking and digesting food so it is important we are getting sufficient energy to meet our daily needs. People often count calories to balance their energy intake (food) with energy expenditure (exercise) in order to influence their weight. In reality, foods with the same calorie content can have different caloric availability; this refers to the number of calories that can actually be utilised after digestion.
For example, 100kcal of sugar and 100kcal of sweet corn will contain the same amount of energy, but our bodies will digest and absorb these foods differently. This means that we can absorb all of the calories in sugar but much less of the calories in sweet corn (2). In general, foods higher in protein and fibre will have a lower caloric availability whilst processed foods higher in sugar will have a greater caloric availability.
Counting macros is another form of calorie counting but also considers the proportion of different food groups. ‘Macros’ is short for macronutrients and consists of carbohydrates, protein and fat. These food groups should be consumed in our diet in large amounts to provide the energy our body needs.
Alcohol is also a macronutrient as it provides a significant amount of calories per gram but is not essential to be consumed in the diet. The Eatwell guide (3) advises the proportions of these food groups we should eat in a day in order to have a healthy, balanced diet.
As well as providing energy, carbohydrates often contain fibre, which is important to support gut health, protein enables growth and muscle repair and fat aids the absorption of certain vitamins and is required for hormone production and function.
Micronutrients consist of vitamins and minerals and should be consumed in the diet in smaller quantities. Macronutrients are important to provide the energy our body needs but micronutrients are essential to utilise this energy and to support a range of body functions including immune function and bone health.
In order to get sufficient amounts of the different vitamins and minerals it is important to eat a balanced and varied diet. Try to include fruit or vegetables with every meal, as they are a good source of vitamins, minerals and fibre.
When tracking calories or macros it is very easy to focus on the quantities of foods rather than their quality. Although you may be hitting your target requirements you may not be making the healthiest choices to support your overall health.
A healthy diet involves a balance between fruit, vegetables, dairy (or dairy alternatives), protein and starchy carbohydrates. This combination should provide the energy, vitamins and minerals required to optimise mental and physical function.
For more information on a healthy diet and to ensure you are achieving your goal to eat five portions of fruit and vegetables per day, sign up to the Great British Veg Out 30 Day Challenge here for free.
About the author:
Chloe French is a Registered Associate Nutritionist spreading her time between working as a freelance Nutritionist and researching the prevalence and severity of food allergies at the University of Manchester. Her aim is to make healthy eating both accessible and interesting. Chloe prioritzes making evidence-based research relevant to our every day life by educating, inspiring and providing tasty and nutritious recipes. This is important to improve our health, performance and energy levels (both mentally and physically).
References
Hargrove, J.L. (2007) Does the history of food energy units suggest a solution to “Calorie confusion”? Nutr J. 17;6:44
Yeo, G. (2019) Gene Eating: The Science of Obesity. Orion Publishing Co. London.
The Eatwell Guide (2018) Public Health England in association with the Welsh government, Food Standards Scotland and the Food Standards Agency in Northern Ireland. Accessed online at: https://www.nhs.uk/live-well/eat-well/the-eatwell-guide/