Macronutrients vs micronutrients
Article by Rhiannon Lambert, BSc MSc RNutr
I’m sure many of us have heard of macronutrients and micronutrients, but what exactly are they, what’s the difference, and why are they important?
“Adequate nutrition is vital if you want your body to be healthy, well maintained, and have the best chance at fighting disease and operating optimally”
Nutrition
As humans, we need an array of nutrients for survival, good health and disease prevention. Each nutrient has a specific set of functions within our body and most can be obtained from the food we eat.
Eating nutritiously enables you to enjoy the sense of wellbeing that comes with good health. Adequate nutrition is vital if you want your body to be healthy, well maintained, and have the best chance at fighting disease and operating optimally. We get our nourishment mostly from macronutrients, which are the dietary main players, but micronutrients are no less important. A balanced diet contains many different types of both.
What is the difference between macronutrients and micronutrients?
The main difference between the two is that the body needs macronutrients in larger quantities compared to micronutrients which are needed in much smaller amounts.
There are many processes the body takes care of without our conscious control (such as breathing, temperature regulation, digestion, and cell repair) that require energy. And, of course, your body requires energy for movement. Each of the macronutrients is required in relatively large amounts every day to support many of your body’s vital functions.
Macronutrients explained
The main macronutrients are carbohydrates, protein and fat and these make up the majority of the food that we eat. Macronutrients are our main source of energy and also provide our body molecules it needs for growth, repair and bodily maintenance.
Carbohydrates
Carbohydrates are the body’s greatest energy source. They provide the body with glucose to use for energy, which can also be stored (as glycogen) for future use. Carbs also play a valuable role in gut health, by providing useful fibre to the digestive tract.
Glucose is the preferred energy source for muscles during strenuous exercise. It is only when the body’s glucose supply is depleted that it turns to fat for energy. The body also requires glucose to fuel multiple unconscious biological processes.
Glucose is essential fuel for the brain, aiding in concentration. Carbohydrates play an important role in generating the brain’s serotonin supply. This mood-regulating hormone is made with tryptophan, an amino acid obtained through protein in the diet. Carbs help to convert tryptophan into serotonin, so eating carbs may help to enhance mood.
Sources of carbohydrates include
Bread
Potatoes
Pasta
Rice
Breakfast cereals
It also includes the sugars found in fruits, vegetables and milk.
Protein
The macronutrient protein is a major player in the diet. It is the body’s building block used to form and repair muscles, skin, hair, and nails, for instance. Protein also enables many of the body’s vital metabolic functions.
Every single cell in the body contains protein, and there are thousands of types found in the body. Proteins form the structure of tissues. They also carry molecules around the body to where they are needed, playing an important role in many chemical reactions that take place, including immune response and the production and deployment of hormones.
Proteins are made up of amino acids. Short chains of amino acids are called peptides (they connect to each other with peptide bonds) while longer chains are called polypeptides or proteins. Protein chains can become complex in structure as more and more chains join and fold in on themselves. The body breaks down protein chains into peptides to use for specific purposes as required. For instance, the hormone insulin is a peptide.
The body can produce many of the amino acids it needs to make peptides and proteins, but nine of them, known as essential amino acids, must be sourced from the diet. Because the body doesn’t store proteins in the same way it does other macronutrients, it needs to consume proteins every day. Numerous studies demonstrate that a diet with adequate protein has major health benefits.
Sources of protein include:
Meat
Fish
Dairy products
Eggs
Beans
Nuts
Pulses
Soya
Tempeh.
Fat
We should aim to get one-third of our calories from fat. The fat we eat is broken down into triglycerides (fatty acid cells combined with glycerol, a type of glucose) that travel in the blood to wherever they will be used or stored.
There are two main types of dietary fats: saturated and unsaturated fats. Unsaturated fats are either monounsaturated or polyunsaturated. Most foods containing fat naturally contain a mixture of different types of fats, so it’s difficult to exclude one type in favour of another. However, we should aim to cut down on saturated fats and opt for more monounsaturated and polyunsaturated fats.
It's important to limit or even avoid the artificial additive transfat due to its links to inflammation, unhealthy cholesterol levels, impaired artery function and insulin resistance.
Sources of fat include:
Animal fats (i.e. butter and lard)
Plant oils and spreads (i.e. olive, coconut and vegetable)
Meat
Dairy products
Avocados
Oily fish
Nuts and seeds
Micronutrients explained
We need vitamins and minerals, known as micronutrients, in much smaller quantities than macronutrients, but they are vital for the body to carry out its functions. In children they are also essential for healthy growth and development.
Because we need macronutrients in much larger quantities than micronutrients, it’s easy to underestimate the importance of the latter and focus more on including the former in the diet. But the absence of micronutrients can lead to severe consequences.
Vitamins
Vitamins can be divided into two main categories:
Water soluble vitamins
Thiamine (Vitamin B1)
Riboflavin (Vitamin B2)
Niacin (Vitamin B3)
Vitamin B5
Vitamin B6
Vitamin B7
Vitamin B12
Folate (Vitamin B9)
Vitamin C
Fat soluble vitamins
Vitamin A
Vitamin D
Vitamin E
Vitamin K
Minerals
The main minerals that we need for good health are:
Calcium
Fluoride
Iodine
Iron
Magnesium
Phosphorus
Potassium
Sodium
Selenium
Zinc
You can get most of your vitamins and minerals from plants. Plant foods come in various shades and colours, and their colour is linked to the nutrients they contain. For instance, orange often indicates the presence of Vitamin A; purples indicate antioxidants; greens contain Vitamin K and iron; and red vegetables contain lots of Vitamin C. So a colourful diet will give you a well-varied nutrient intake.
The daily requirement of each micronutrient varies between individuals, but if your diet is healthy and balanced, including foods from both plants and animal sources, you are likely to be ingesting all the micronutrients your body needs without the need for supplements.
What is deficiency?
Nutritional deficiencies usually happen when we do not get enough of a certain nutrient. The World Health Organisation suggests that the most common deficiencies, such as anaemia, rickets, and osteoporosis are caused by inadequate micronutrient intakes (iron and vitamin D, respectively).
For those who don’t eat animal products, a well thought through diet alongside targeted supplementation will provide the essential nutrients you need. Some examples of some micronutrients that may be lacking in a vegan diet, due to the fact that most sources are from animal based products, include vitamin D, vitamin B12, and calcium.
Vitamin D
Vitamin D is an important micronutrient as it is the only vitamin that may be produced by the body. Getting enough vitamin D is important as it is needed for healthy teeth, bones, and muscles, as well as to support the healthy functioning of the immune system. There are limited food sources that contain vitamin D, but some include oily fish, mushrooms, egg yolks, and fortified foods such as plant-based milks and breakfast cereals. You can read more about what vitamin D is and the different types (vitamin D2 vs D3), how it is made in the body, and how you can increase your dietary intake of vitamin D here.
Calcium
An adequate intake of calcium is needed alongside vitamin D intake to help support healthy bones and teeth. In addition, it is also important in helping the blood to clot normally, regulating muscle contractions including your heart. It can be found in dairy products such as milk and cheese, green leafy vegetables such as kale, fish where you eat the bones such as sardines, and fortified products such as plant-based milks and yoghurts and flour. A diet which lacks calcium may increase the risk of osteoporosis and osteomalacia.
Supplements
At Rhitrition+ we offer both a vegan Vitamin D oral spray, needed by the majority of population as well as a Vegan Multivitamin capsule, which may be needed to support a healthy and balanced diet.
If you think you might be deficient in macro or micronutrients and before taking supplements or making big changes to your diet, contact your GP or a registered nutritionist or dietitian as they will be able to offer you bespoke and individualised advice to suit your nutritional needs. Blood tests can help to diagnose deficiencies, and supplements can then be prescribed to help correct them.
