The Macro Breakdown
I'm sure you're familiar with the term 'macronutrients'. But what exactly are they and what are they made up of? What are their roles in the human body and what are good sources of these nutrients? Read on, and I'll tell you everything you need to know about our three major fuel sources!
What are macronutrients?
Macronutrients are the nutrients needed by our bodies to produce cellular energy and growth, and are needed in large amounts - compared to micronutrients (such as vitamins and minerals), which are needed in much smaller amounts. The three macronutrients are carbohydrates, fats and protein.
Carbohydrates are our body's preferred fuel source, and they are made up of sugars, starches and cellulose. Cellulose is indigestible for our bodies, and therefore passes through our digestive tract, while starches are broken down into sugars after we consume them, and used to produce cellular energy. Carbohydrates can be divided into four groups, depending on their structure, i.e. how many sugar molecules grouped together they are composed of. These are: Monosaccharides, disaccharides, oligosaccharides and polysaccharides. You may have heard people refer to carbs as 'simple' or 'complex', and generally, the more sugar molecules make up the carbohydrate's chain, the more 'complex' a carb is, such as oligosaccharides and polysaccharides.
A 'complex' carb may also mean that is from a wholefood, unrefined source that also contains significant amounts of dietary fibre, vitamins and minerals, whereas a 'simple' carb is more processed, and is a quick source of energy but contains very little other nutrients , such as fibre. These simple carbs, mostly monosaccharides and disaccharides, are usually broken down and absorbed by the body very quickly, due to the very low fibre content (fibre is what slows down absorption!). This may lead to quick energy and blood sugar spikes, while providing the body with very little nutritional value, and are often easy to over-eat on due to not being very filling or satiating.
In contrast, complex carbs take much longer to break down and provide a slow-releasing, and long-lasting, supply of energy, due to their high fibre content. They are also generally filled with nutrients such as B vitamins and essential minerals, and much harder to overconsume due to being so filling.
Of course, the digestion and absorption of different foods and meals can vary widely and be influenced by a great number of factors (including which other macronutrients are eaten as part of that meal), but in general, the more whole and unprocessed your carbohydrate sources are, the more health-promoting and nutrient dense they are!
Some nourishing, wholesome carb sources include:
Vegetables, especially root vegetables (sweet potato, pumpkin, potato)
Legumes, such as beans and lentils
Whole grains, including quinoa, buckwheat, millet, brown rice, rolled oats, whole wheat, barley and amaranth
Fats are composed of fatty acids or triglycerides, and are broken down into these when we consume them. They are essential for the health of our skin and cell membranes, hormone regulation, brain function, nutrient absorption and immune system. Fats are the most energy-dense of the three macronutrients, and we don't want to be getting too much of our daily energy intake from fat, however eating good quality fats as part of daily diet is not only healthful but essential for proper health and function of our bodies!
Fats can be saturated, monounsaturated or polyunsaturated (most foods include a combination of these three), with the unsaturated fats being associated with a large number of health benefits. The essential fatty acids, omega 3s and 6s, cannot be produced by our own bodies, therefore need to be obtained through our diet.
Trans fats are another kind of fat, occurring in processed foods (produced through heating volatile oils to change their chemical structure!) and naturally in animal products. This type of fat is best avoided as much as possible as evidence shows it's inflammatory and associated with a range of negative health effects. Quality is very important when it comes to fats, such as nuts, seeds and oils, as poorly processed or stored fats may turn rancid and become harmful to health.
Nourishing, whole-food fat sources include:
Nuts and seeds
Proteins are made up of amino acids to form large and complex molecules of different sizes. These amino acids building blocks are essential for a wide variety of biochemical functions, processes and structures within the human body, including our metabolism, hormone function, immune system, muscle tissue synthesis and repair, DNA production and enzyme function (and more!).
Protein can come from both animal and plant sources, and eating a variety of different protein-containing foods ensures you are getting all the essential amino acids necessary for optimal health and body function.
Wholesome and nourishing plant-based protein sources include:
Nuts and seeds
Legumes, such as beans, chickpeas and lentils
Tofu and tempeh
Whole grains, such as brown rice, rolled oats, quinoa, buckwheat, amaranth and millet
And smaller amounts in vegetables, especially leafy greens
In order to have a balanced, healthy diet, we should be aiming to include each of these three macronutrients in our meals in the amounts that support good health, energy and activity levels. This provides our bodies with the optimal fuel we need to feel and function our best, ensure we stay satiated and satisfied, balance our hormones and blood sugar levels, and provide us with all the nutrients we need.
Exactly how much we need of each of them will vary considerably from person to person, so if you feel you are having trouble knowing what or how much to eat to support your body, I highly recommend seeing a qualified nutritionist (such as myself!) who can help get you on the right track with fuelling your body and reaching your health goals! xx