Everybody needs nutrients for energy and growth, as well as other functions of the human body, and the term macronutrient refers to a kind of ‘go large’ version – technically a supersize dose. Large amounts of the key macronutrients, comprising carbohydrates, fats and proteins, are needed to sustain everyday living. So What The Deal Yo with macronutrients? Here’s a quick guide to the facts.
This is where the body’s energy supplies come from; proteins, fats and carbs offer different amounts so becoming familiar with what they deliver is important when aiming to build body health and strength.
For example, a gram of fat provides about 37 Kj whereas a gram of protein or carbs supplies about 17 Kj each. It’s pretty obvious at this stage that, gram for gram, fats deliver more energy, but overdoing them is not really the way to go.
The key is getting the balance between these three macronutrients just right, as research shows relative proportions of nutrients can decrease or increase the possibility of heart disease. On average, about 55% of energy needs should come from carbs, about 30% from fats and about 15% from proteins.
The Magic World Of Carbohydrates
The major source of energy to human beings, carbs don’t always get a good press, especially among people anxious to follow weight-loss diets. These tend to focus on carbohydrate reduction. Yet a proportion of the carbohydrate people consume is converted into a type of starch called glycogen and stored away in the liver and the muscles for future use. This is like a sort of forward planning exercise by the body.
Even carbohydrates from some vegetables and fruit that are technically ‘non-digestible’, and often labelled as dietary fibre, play a part in keeping those inner tubes, such as the large intestine, in good shape and also assist with the all-important removal of bodily waste. Did someone say “too much information?”
The Building Blocks Of Protein
Moving on from one delightful image to another, a spot of dedicated processing by the human gut results in humble proteins being broken down into amino acids. These amino acids can be used in three different ways:
• Building blocks help humans to produce new proteins that repair damaged tissue, promote growth and manufacture essential enzymes and hormones. They also support the immune function. Picture a virtual reality equivalent such as SimCity.
• Amino acids also produce energy to fuel human activity, just as many video games let participants collect energy tokens.
• Finally, amino acids act as a kind of catalyst; they provide starting materials in the production of other compounds that are needed by the body. The process is a bit like acquiring a virtual reality headset: it introduces the prospect of exciting times ahead, but doesn’t actually deliver until it’s connected up to a program.
Among the 20 different amino acids that make up the body’s collection of proteins, eight are described as essential. If the non-essential ones are not provided in the usual diet, then they can be synthesised by the liver. In general, when proteins from animal sources are consumed, or when vegetarians eat a variety of plant sources, then all of the essential amino acids are present.
Fats & Energy
Just like poor old carbs, fats have a bit of a bad reputation, particularly in relation to heart disease and weight gain; however, it’s important to remember that some fat in the diet is actually essential for health and wellbeing. Fats and oils should account for an average of 30% of daily energy requirements. As well as supplying energy, fats are needed to assist with the absorption of the important vitamins A, D, E and K, plus carotenoids, provide foods with flavour and texture and supply fatty acids that the body needs but cannot make, for example omega-3.
Don’t Be Afraid
Knowledge is power, so when assessing the need for macronutrients it’s important to keep things in perspective.
In terms of fats, for example, using unsaturated fats in the diet (olive oil, avocados, nuts and rapeseed oil) instead of saturated fats (meat, butter and cream) and trans fats (commercially produced baked goods, snack foods, fast foods and some margarines) will help to reduce your risk of heart disease.
Think about it before taking a major life decision – don’t cut back on carbs unless you are actively trying to lose weight and remember to make the most of your proteins and unsaturated fats.
Remember that the right balance of macronutrients is good for you.