What are macronutrients and what are micronutrients?

Macronutrients and micronutrients are categories of nutrients dietitians and nutritionists use to describe what we eat.

You may have heard of counting ‘macros’ or macronutrients. Is this the same as counting calories?

How does macronutrient counting help you live healthily? And what is the difference between macronutrients and micronutrients?

Macronutrients and micronutrients

Nutrients available in food are divided into two groups – macronutrients and micronutrients.

Both macronutrients and micronutrients are necessary for our bodies to function. They differ mainly in how much we need them.

Macronutrients

We need macronutrients – proteins, carbohydrates and fats – in large quantities every day. In some sources, alcohol is also classified as a macronutrient.

Although each macronutrient has specific properties and functions, they have one thing in common – they are all sources of energy:

• 1 g of protein contains 4 Kcal (contained in eggs, meat, fish, dairy products, tofu…).
• 1 g of carbohydrate contains 4 Kcal (contained in cereals, fruit, berries, vegetables, legumes, honey…).
• 1 g fat contains 9 Kcal (contained in oils, fats, butter, meat, nuts, avocados…).
• 1 g of alcohol contains 7 Kcal.

Proteins, carbohydrates and fats are broken down (digested) in the gut into their basic components:

• Proteins – into amino acids.
• Carbohydrates – into sugars.
• Fats – into fatty acids and glycerol.

From these basic components, the body builds the substances it needs for growth and self-maintenance (anabolism), including other carbohydrates, proteins and fats

Micronutrients

Although macronutrients are needed by our bodies in much greater quantities than micronutrients, this does not mean that micronutrients are less important.

The term ‘micronutrients’ refers to vitamins and minerals, which can be further subdivided:

• Macrominerals (e.g. calcium, phosphorus, magnesium, sodium, potassium, sulphur…).
• Trace elements (e.g. copper, iodine, iron, manganese, zinc…).
• Water-soluble vitamins (e.g. vitamin C and the B vitamin complex – thiamin, riboflavin, niacin, pantothenic acid, pyridoxine, biotin, folic acid and cobalamin).
• Fat-soluble vitamins (e.g. vitamins A, D, E, K…).

The body cannot synthesise minerals and, in most cases, vitamins, so we have to get them from food.

In other words, we need to eat a balanced diet so that our bodies not only get all the minerals and vitamins they need but also get them in the quantities they need.

Functions of macronutrients and how much we need them

All nutrients are important for our bodies to function properly.

But.

A balanced and varied diet is essential when slimming, as it is more difficult to provide everything the body needs during a calorie deficit.

In other words, the less we eat, the more attention we need to pay to what we eat.

Therefore.

Let’s look at macronutrients vital for us, why we need them and how much of them we need.

Proteins

Proteins are often referred to as the building blocks of the body because they are the main components of our body tissues. They are also essential for the immune system and for muscle development and function (if your body lacks protein, your muscles won’t grow, no matter how hard you train).

Protein is also needed to make enzymes, hormones, antibodies and other important molecules.

Hence.

Protein’s main role is to provide us with amino acids – the building blocks from which our bodies then build muscle, organs, brain… tissues and everything it needs.

Amino acids are classified according to their side chain properties, structure, use…

But.

When it comes to nutrition, they are usually classified based on our body’s ability to synthesise them or not:

1. Essential amino acids – amino acids that the body cannot synthesise and must be obtained through diet. There are nine essential amino acids: histidine, isoleucine, leucine, lysine, methionine, phenylalanine, threonine, tryptophan and valine.
2. Non-essential amino acids – amino acids that can be synthesised by the body and therefore are not necessarily required in the diet, for example – alanine, asparagine, aspartic acid, cysteine, glutamic acid, glutamine, glycine, proline, serine and tyrosine.
3. Conditionally-essential amino acids – amino acids that the body can produce under normal, healthy conditions, but under certain conditions (such as pregnancy or illness) become essential and must be taken in the diet.

How much protein do we need?

The recommended protein intake depends on your age, sex, weight and level of physical activity. Adults should have at least 0.8 grams of protein per kilogram of body weight each day, but athletes and people with high physical activity need much more protein.

Read more about how much protein you should eat per day HERE.

Carbohydrates

Carbohydrates are a group of compounds made up of simple sugars.

Carbohydrates are our body’s primary source of energy. They play an important role in metabolism and are particularly important for the functioning of the brain, liver and red blood cells (as the main or the only energy source).

But.

Carbohydrates are different:

1. Simple carbohydrates – the simplest form of carbohydrate, consisting of only one or two sugar units. Simple carbohydrates raise blood sugar levels quickly and are therefore also called “fast” carbohydrates (table sugar, syrups, lemonades, fruits and fruit juices…).
2. Complex carbohydrates contain more than three sugar units linked in long, complex chains. They are digested more slowly, so blood sugar rises slowly and is maintained for longer. In other words, we don’t get a lot of energy at once (as with simple sugars), but slowly over a longer period (peas, beans, whole grains, vegetables…).
3. Starch (the way plants store glucose) is a natural polymer or polysaccharide – a long chain of molecules of the same type. Starch is made up of glucose molecules. It can come in two forms: amylose and amylopectin. Starch takes longer to digest and absorb than simple carbohydrates because of its complex structure. Starch causes a slower and more gradual rise in blood sugar (potatoes, bread, rice, pasta, cereals…).
4. Fibre is a complex carbohydrate consisting of indigestible plant parts or compounds that pass relatively unchanged through the stomach and intestines. Fibre is divided into soluble and insoluble. Both are beneficial to health and should be included in our daily diet to promote gut health. Most plant foods contain a mixture of both types of fibre (whole grain products, fruits and vegetables).

How much carbohydrate do we need?

This depends mainly on your weight and energy requirements – the higher your weight and/or physical activity, the more energy you need.

Under normal circumstances, carbohydrates should contribute around 45-65% of your total daily calorie intake.

Read more about carbohydrates HERE.

Fats

Fats are a concentrated energy source, providing our bodies with fatty acids.

But.

Fat is not only a source of energy – it also plays an important role in brain function, organ insulation and protection, and body processes such as maintaining healthy cell membranes, hormone production and absorption of vitamins A, D, E and K, etc.

Fats also vary:

1. Saturated fats (butter, pork, hard cheeses, coconut oil…).
2. Trans fats (margarine, industrially produced snacks (crackers, chips, etc.), deep-fried products…).
3. Monounsaturated fats (olive and rapeseed oil, avocados, nuts…).
4. Polyunsaturated fats (oily fish (salmon, trout, mackerel…), soybean oil, flaxseeds, walnuts…).

Each type of fat has its specific role and is needed in different amounts.

Saturated fats are often considered “unhealthy” because their excessive consumption causes an increase in LDL (“bad”) cholesterol in the blood, which is associated with an increased risk of cardiovascular disease.

Unsaturated fats include monounsaturated and polyunsaturated fats and can help to reduce blood cholesterol and, therefore, the risk of cardiovascular disease.

Trans fats (also called trans-unsaturated fatty acids) are a type of unsaturated fat found naturally in small amounts in foods (e.g. beef, sheep and goats, meat, milk and dairy products). Natural trans fats are not harmful to health if consumed in moderation.

But.

Artificial trans fats (also known as partially hydrogenated fats) are dangerous to our health. These fats are created by chemically modifying vegetable oils to make them solid at room temperature, thus giving them a much longer shelf life. These chemically modified vegetable oils are widely used in the food industry because they are cheaper than healthy fat alternatives.

How much fat do we need?

Fat should make up about 20-35% of your total daily calorie intake. It is important to choose healthy fats, such as those found in nuts, seeds, avocados and oily fish while limiting the intake of saturated and trans fats found in industrially processed and deep-fried foods.

Read more about why fats should not be excluded from your diet HERE.

Macronutrients and weight loss

To lose weight, you need to be in a calorie deficit – taking in fewer calories through food and drink than your body uses.

In other words, you need to eat less, or exercise more, or both.

And.

As we eat less, it is likely, that we are not getting enough of some essential nutrients.

And.

If your body is lacking something – it stops working the way it should.

Key takeaways

The USDA Dietary Guidelines for Adults recommend the following macronutrient breakdown:

• Protein – 10-35% of daily calorie intake.
• Carbohydrates – 45-65% of daily calorie intake.
• Fat – 20-35% of daily calorie intake.

The situation with minerals and vitamins is a bit more complicated – we know how much of them our bodies need, but as there are so many of them, the calculations are very complicated and often inaccurate because even in the same vegetables, fruits, etc., the amount of vitamins and minerals can be very different (depending on where they are grown, how they are grown, etc.).

So, what is the way out?

Diversify your diet by including not only different food groups (meat, cereals, dairy, vegetables, fruit…) but also a variety of meats (turkey, chicken, beef/fillet, liver, etc.), a variety of vegetables and fruits, seeds, nuts, etc.

Eat a balanced diet, move and – be healthy!