They say food is one of life’s simple pleasures but, when it comes to eating for health,the science can get complex. But no matter your food philosophy or diet plan, there’s one thing you shouldn’t ignore: the importance of macronutrients. Nature’s body fuel, these bad boys are the basis of all things edible and essential for our nutritional needs.
Food before calories
So what exactly are macronutrients? Technically, they are energy-giving chemical substances which need to be consumed by organisms in large quantities. To you and me, they are the common food types we call carbohydrates, protein and fat. Foods generally contain different proportions of each, but can be made up of just one.
Macronutrients work by providing us with units of energy we know as calories. Our bodies then use these calories for normal functioning and growth. Carbs and protein provide 4 calories per gram, whilst fat provides 9 calories per gram.
As well as macronutrients, our bodies also need micronutrients – vitamins and minerals. Unlike macronutrients, micronutrients are only required in trace amounts. Some of the most important ones include calcium, vitamin B12, zinc, potassium and vitamin C.
Getting the right balance of each macronutrient – and enough of every micronutrient – in our diets is critical to good health. However, in our diet obsessed world we often lose sight of this, worrying more about the calories we consume than the nutritional balance of the food we are consuming.
The healthy ranges
According to U.S.guidelines, we should be consuming 45-65 per cent of our energy for carbs, 10-35 per cent from protein and 20-35 per cent from fat for optimum health and wellbeing. Australia’s figures are similar, with the National Health and Medical Research Council recommending 45-65 per cent carbs, 15-25 per cent protein and 20-35 per cent fat.
These ranges are based on numerous scientific studies carried out to assess the role macronutrients play in health and chronic disease outcomes and are intended for individuals looking to maintain a healthy BMI. However,many diet plans manipulate these percentages in pursuit of a different outcome: weight loss.
Tipping the balance
Depending on the theory behind the diet, carbs, proteins and fats have been feared and favored to varying degrees. In the nineties, fat was equated with getting fat. The solution? Remove it completely. Next came the noughties which demonised carbs, sold to us in the form of the Atkins and South Beach diets which severely limited them in favor of protein and fat. Unfortunately, the trouble with shifting macronutrient ratios is that whilst it may induce weight loss, it can be detrimental to health.
Other diets take a more balanced approach to macros. The One One One, for example, recommends a single serving of each at every meal. The downside is that it doesn’t consider the types of carbs, proteins and fats – so eating a Big Mac is considered a nutritionally sound meal. Another, the 40.40.20 is similar but also considers the quality of the macros consumed.
This is important because not all macronutrients are created equal. As our understanding of nutrition has widened, not only have we come to realize the value of macronutrient balance for health, but we also have a much better understanding about the importance of the types of carbs, proteins and fats we consume in terms of their implications for health.
Good versus bad carbs
Carbs are our body’s primary source ofenergy. They provide the fuel that powers our muscles and major organs, in particular our brains. Carbs come in two types: sugars and starches. In Australia, as in most western countries, our intake of sugar is typically too high.
Just like the Atkins diet, many of today’s trending diets such as Paleo and ketone, say we should be reducing carbs, favouring protein and reducing our sugar intake– today’s public health enemy number one. However, the problem with this is that carbs are the body’s preferred source of energy – your brain needs them to maintain alertness and concentration.
The key to carbs is knowing your good from your bad. Good carbs or complex carbs include foods such as whole grains, potatoes and legumes. Because they contain chains of sugar molecules they take longer for your body to break down. By comparison, bad carbs are simple sugars which are quick to digest such as those found in processed foods like white breads, pasta and cakes.
Most good carbs have a low glycaemic index (GI) which means they release less sugar at a more consistent rate. Bad carbs, on the other hand, release sugar in spikes leading not only to headaches and fatigue but to other more serious health problems such as obesity and diabetes.Fruits have a high GI but are okay to eat because they also contain fibre which slows the release process.
From fatty to lean
The main function of protein is to support the body’s normal tissue maintenance and growth. It is found in food such as meat, poultry and fish, eggs, cheese, nuts and seeds, soy and legumes. Almost 99 per cent of Australians meet their daily recommended intake.
Ensuring you not only eat the right amount of protein, but the right kind of protein is essential for health. Many, such as red meats and full-fat dairy products, are high in saturated fat and linked to cardiovascular disease. Because of this, ‘leaner’ proteins like those found in chicken, fish, nuts and oils are recommended.
The Australian Dietary Guidelines emphasise that our meat consumption should be limited to lean – containing less than 10 per cent fat. In addition, processed meats, such as salami, ham and beef jerky should be avoided due to their high salt content, low nutritional value and links to cancer.
Non-animal products can be packed with healthy protein. This includes foods like beans, quinoa, tofu and nuts.
Say no to saturated
Fats have traditionally been given a bad press but they are essential for health as they support a number of bodily functions. One of the biggest concerns with fat is that it is high in calories, but in reality this is only a concern if high consumption of fat is causing you to exceed your daily calorie limit.
Just like carbs and proteins, fats fall into two categories – good and bad. Saturated and trans fats are the potentially harmful ones. Saturated fats raise your total blood cholesterol and can increase your risk of cardiovascular disease and diabetes. Trans fats, which are generally processed oils, have a similar negative impact on health.
What we should be eating instead is healthy or unsaturated fats. This includes: monounsaturated fatty acids which occur in a variety of foods and oils; polyunsaturated fatty acids which tend to occur in plant-based food and oils; and omega-3 fatty acids found in fatty fish and certain oils, seeds and nuts.
The world of nutrition and macronutrients can be a complex one, especially if you are looking to lose weight as well as stay healthy. Any eating plan which excludes or significantly reduces one or more macronutrient should be avoided. Ultimately, if you stick to the guidelines – you can count your macro intake with apps such as My Macros+ or MyFitnessPal – and limit the bad carbs, proteins and fats in your diet, you can optimise your health and achieve your dietary goals. And if you find you’re generally rushed off your feet, you can make it even easier by simplifying your meal preparation.
Check out the following infographic which provides a handy breakdown of the macronutrients essential for a healthy diet.